Thèses : « Sodium-ion batterie »

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Farina, Luca. « Sodium Ion battery for energy intensive application ». Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019.

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In questa tesi viene proposto uno studio sulle batterie agli ioni sodio e lo sviluppo di un innovativo metodo di studio che sfrutta il microscopio a scansione elettronica (SEM). Le batterie ioni sodio (SIB) sono una tecnologia innovativa che ha interessato gli studiosi soprattutto negli ultimi anni, in virtù della loro competitività rispetto alle più diffuse batterie agli ioni litio (LIB). Infatti, rispetto a queste ultime, caratterizzate dalla presenza di metalli rari e costosi e dal cobalto, un metallo altamente inquinante, le SIB sono costituite da sodio, tra i metalli più abbondanti sulla crosta terrestre, e soprattutto non necessitano di cobalto, risultando così molto più economiche. In questa tesi si proporrà lo studio di un substrato per lo sviluppo delle batterie anode-free. Negli ultimi studi sta prendendo piede l’idea di realizzare una batteria senza anodo in quanto risulta complesso un materiale con caratteristiche di intercalazione buone per questo elettrodo. Si procede poi a riportare la caratterizzazione del substrato in analisi. In particolare viene presentato un innovativo porta campioni per lo studio con SEM, completamente progettato e realizzato appositamente per il presente studio. Si tratta di un sistema air-tight che protegge il campione dall’ossidazione. La caratterizzazione d’immagine con il SEM risulta particolarmente utile in quanto permette di capire come procede la deposizione del sodio sul substrato studiato. Vengono infine presentati i risultati della caratterizzazione del substrato considerato. L’intera tesi è stata portata avanti all’interno dell’Energy Storage Group del College of Engineering, presso Swansea University, Swansea (UK).

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Michelet, Cédric. « Recherche exploratoire de nouveaux matériaux d'électrode négative pour batterie sodium-ion ». Nantes, 2014. http://archive.bu.univ-nantes.fr/pollux/show.action?id=d046bc78-38d0-480a-9562-5ec81ce5bca2.

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Les accumulateurs lithium-ion sont devenus indispensables ces dernières années. Pour des raisons d’accès aux ressources et de coût de l’élément alcalin, un nouveau champ de recherche s’intéressant aux accumulateurs sodium-ion a récemment émergé. Parmi les grands défis posés par ce nouveau dispositif, le travail développé durant cette thèse a pour but l’exploration de nouveaux matériaux d’électrode négative. Deux types de matériaux ont été étudiés : l’étain métallique, et les chalcogénures AV4S8 (A=Ga, Ge). L’étain a été obtenu sous forme dense ou dendritique par dépôt électrochimique. En batterie sodium-ion, ce matériau présente des propriétés intéressantes, puisque durant la première décharge, une capacité spécifique de 1 Ah/g à un potentiel de réaction inférieur à 0,6 V par rapport à Na+/Na0 est obtenue. Cependant, une expansion volumique de 350% durant la sodiation entraine une perte importante de capacité qui passe sous les 100 mAh/g après une dizaine de cycles. Les chalcogénures AV4S8 (A=Ga, Ge) ont été le principal sujet d’étude de ce travail de thèse. Le mécanisme de réaction avec le sodium, proche d’un mécanisme de conversion, a été étudié par diffraction des rayons X in situ, par spectroscopie d’absorption des rayons X et par spectroscopie de perte d’énergie des électrons afin d’observer l’évolution du degré d’oxydation des éléments intervenant dans la réaction avec le sodium. Ces matériaux possèdent des caractéristiques électrochimiques remarquables, avec une capacité spécifique initiale de plus de 800 mAh/g à bas potentiel et une très bonne tenue en cyclage
Lithium-ion batteries have become essential in recent years. Due to both the difficult access and the cost of the alkaline element, a new field of research concerning sodium-ion batteries has recently emerged. Among the major challenges inherent to this new battery type, the aim of the work developed during this PhD thesis is to explore new negative electrode materials. Two material types have been studied: metallic tin, and the chalcogenides AV4S8 (A=Ga, Ge). Tin was obtained with dense or dendritic form by electrolchemical deposition. In sodium-ion battery, this material presents interesting properties since during the first discharge, a specific capacity of 1 Ah/g at a working potential below 0. 6 V relative to Na+/Na0 can be obtained. However, a volume expansion of 350% during the sodiation causes a significant capacity loss, which is under 100 mAh/g after around ten cycles. The AV4S8 chalcogenides (A = Ga, Ge) have been the main subject of this PhD thesis. The reaction mechanism with sodium, close to a conversion mechanism, has been studied by in situ X -ray diffraction, X-ray absorption spectroscopy and electron energy loss spectroscopy in order to observe the oxidation number evolution of the elements involved in the reaction with sodium. These materials exhibit remarkable electrochemical properties, with an initial specific capacity of more than 800 mAh/g at low potential with excellent capacity retention upon cycling

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FIORE, MICHELE. « Nanostructured Materials for secondary alkaline ion batteries ». Doctoral thesis, Università degli Studi di Milano-Bicocca, 2020. http://hdl.handle.net/10281/262348.

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Thanks to their superior energy and power density, lithium-ion batteries (LIBs) currently dominate the market of power sources for portable devices. The economy of scale and engineering optimizations have driven the cost of LIBs below the 200 $/KWh at the pack level. This catalyzed the market penetration of electric vehicles and made them a viable candidate for stationary energy storage. However, the rapid market expansion of LIBs raised growing concerns about the future sustainability of this technology. In particular, lithium and cobalt supplies are considered vulnerable, primarily because of the geopolitical implications of their high concentration in only a few countries. In the search for the next generation secondary batteries, known as post-lithium ion batteries, candidates that do not use rare metals have been extensively investigated in the last 10 years. Sodium-ion batteries (SIBs) attracted considerable attention thanks to the high abundance of the precursors and wide distribution of sodium on the earth's crust. As a matter of fact, as it will be pointed out during the dissertation, it is not straightforward to allocate the reduction of the price of the alkaline ion precursors to the reduction of the battery price. However, the difficulties in the supply of raw materials for LIBs, such as shortages in lithium carbonates and cobalt ores, could make lithium and cobalt-free systems, such as SIBs, attractive and cost-competitive alternatives. Compared to other, more exotic chemistries including Ca2+, Mg2+ and Al3+ batteries, SIBs are nowadays considered one as the most promising alternative to LIBs. Despite the extensive research, anode materials for SIBs still represent a serious problem for the commercial exploitation of this technology. Accordingly, the doctoral research on SIBs has been focused on anode materials. In particular, the attention was directed towards conversion oxides. Compared to intercalation materials, conversion-based ones have higher capacities but are more challenging to deal with because of the high volume variation during cycling. This challenge was addressed by material's nanostructuring and morphology control which proved to significantly reduce the pulverization of the active material. Different anode candidates have been studied during the doctoral work. Cobalt oxide nanofibers have been here explored as a first prototype for conversion materials in sodium ion batteries. The sodiation-desodiation mechanism is analyzed by means of ex situ XRD which led to a deeper understanding of the conversion reaction in SIBs. A cost-effective and environmentally benign alternative based on iron oxide is then considered. The limits of iron (III) oxide are tackled by combining the advantages of the nanostructuring and the doping with an aliovalent element. Si-doped Fe2O3 nanofibers are synthesized via an easy scalable process based on the electrospinning method. It is found that Si-addition improves the transport properties as well as induces changes in the crystal structure and morphology. In the final section of the thesis, potassium-ion batteries (KIBs) are examined as a promising alternative to sodium ion batteries. KIBs exhibit all the benefits of SIBs, with the additional advantage that graphite, can reversibly accommodate K-ions. On the positive side, Potassium manganese hexacyanoferrate (KMnHCF), has been reported to provide high operating voltages and satisfactory capacity retention. The proposed research activity presents the use of an ionic liquid based electrolyte compatible with the most promising anode and cathode for KIBs. In addition, a high-throughput optimization of the KMnHCF synthesis is reported. The selected candidates are then fully characterized, and their electrochemical properties investigated. The optimized material exhibits the highest ever reported coulombic efficiency for the KMHCF. This find, opens up the possibility of highly efficient, high energy potassium ion batteries.
Thanks to their superior energy and power density, lithium-ion batteries (LIBs) currently dominate the market of power sources for portable devices. The economy of scale and engineering optimizations have driven the cost of LIBs below the 200 $/KWh at the pack level. This catalyzed the market penetration of electric vehicles and made them a viable candidate for stationary energy storage. However, the rapid market expansion of LIBs raised growing concerns about the future sustainability of this technology. In particular, lithium and cobalt supplies are considered vulnerable, primarily because of the geopolitical implications of their high concentration in only a few countries. In the search for the next generation secondary batteries, known as post-lithium ion batteries, candidates that do not use rare metals have been extensively investigated in the last 10 years. Sodium-ion batteries (SIBs) attracted considerable attention thanks to the high abundance of the precursors and wide distribution of sodium on the earth's crust. As a matter of fact, as it will be pointed out during the dissertation, it is not straightforward to allocate the reduction of the price of the alkaline ion precursors to the reduction of the battery price. However, the difficulties in the supply of raw materials for LIBs, such as shortages in lithium carbonates and cobalt ores, could make lithium and cobalt-free systems, such as SIBs, attractive and cost-competitive alternatives. Compared to other, more exotic chemistries including Ca2+, Mg2+ and Al3+ batteries, SIBs are nowadays considered one as the most promising alternative to LIBs. Despite the extensive research, anode materials for SIBs still represent a serious problem for the commercial exploitation of this technology. Accordingly, the doctoral research on SIBs has been focused on anode materials. In particular, the attention was directed towards conversion oxides. Compared to intercalation materials, conversion-based ones have higher capacities but are more challenging to deal with because of the high volume variation during cycling. This challenge was addressed by material's nanostructuring and morphology control which proved to significantly reduce the pulverization of the active material. Different anode candidates have been studied during the doctoral work. Cobalt oxide nanofibers have been here explored as a first prototype for conversion materials in sodium ion batteries. The sodiation-desodiation mechanism is analyzed by means of ex situ XRD which led to a deeper understanding of the conversion reaction in SIBs. A cost-effective and environmentally benign alternative based on iron oxide is then considered. The limits of iron (III) oxide are tackled by combining the advantages of the nanostructuring and the doping with an aliovalent element. Si-doped Fe2O3 nanofibers are synthesized via an easy scalable process based on the electrospinning method. It is found that Si-addition improves the transport properties as well as induces changes in the crystal structure and morphology. In the final section of the thesis, potassium-ion batteries (KIBs) are examined as a promising alternative to sodium ion batteries. KIBs exhibit all the benefits of SIBs, with the additional advantage that graphite, can reversibly accommodate K-ions. On the positive side, Potassium manganese hexacyanoferrate (KMnHCF), has been reported to provide high operating voltages and satisfactory capacity retention. The proposed research activity presents the use of an ionic liquid based electrolyte compatible with the most promising anode and cathode for KIBs. In addition, a high-throughput optimization of the KMnHCF synthesis is reported. The selected candidates are then fully characterized, and their electrochemical properties investigated. The optimized material exhibits the highest ever reported coulombic efficiency for the KMHCF. This find, opens up the possibility of highly efficient, high energy potassium ion batteries.

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Huynh, Le Thanh Nguyen. « Les accumulateurs au sodium et sodium-ion, une nouvelle génération d’accumulateurs électrochimiques : synthèse et électrochimie de nouveaux matériaux d’électrodes performants ». Thesis, Paris Est, 2016. http://www.theses.fr/2016PESC1123/document.

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Les accumulateurs au lithium jouent un rôle important comme source d'alimentation pour les appareils électroniques portables en raison de leur forte capacité gravimétrique et volumétrique et leur haute tension. En outre, la technologie lithium-ion est la mieux placée pour une application à grande échelle, telle que le véhicule électrique, ce qui pose un problème de ressource et à terme, de coût. Une des réponses envisagées sur le plan économique et environnemental est le développement d’accumulateurs sodium-ion. Dans tous les cas, le problème scientifique consiste à proposer des matériaux d’insertion des ions sodium avec un caractère réversible de la réaction électrochimique, et une durée de vie compétitive par rapport aux systèmes au lithium. Le travail présenté se situe dans cet effort de recherche. Les potentialités de matériaux dérivés du pentoxyde de vanadium, de structure 2D, sont étudiées comme composés d’intercalation du sodium: le composé de référence V2O5, le bronze performant dérivé de V2O5 de formule K0,5V2O5, ε’-V2O5, ainsi que le composé au manganèse de type lamellaire : la birnessite sol-gel et sa forme dopée au cobalt. Les relations structure-électrochimie sont élucidées à travers une étude combinant propriétés électrochimiques, diffraction des Rayons X et spectroscopie Raman des matériaux à différents taux d’insertion, en fin de réaction et après cyclages galvanostatiques. De nouvelles phases sont obtenues et des capacités spécifiques comprises entre 100 et 160 mAh/g dans le domaine de potentiel 4V-1V peuvent être obtenues avec parfois une stabilité remarquable comme dans le cas de NaV2O5 et ε’-V2O5
Since commercialization, Li-ion batteries have been playing an important role as power source for portable electronic devices because of high gravimetric, volumetric capacity and high voltage. Furthermore, the lithium-ion technology is best suited for large-scale application, such as electric vehicles, which poses a resource problem and ultimately cost. On the contrary, sodium is a most abundant element, inexpensive and similarly properties as lithium. In order to solve the problem of lithium raw resource, sodium is proposed as a solution for next generation power source storage. This work investigates the potential derivative vanadium pentoxide materials as sodium intercalation compounds: the V2O5 reference compound, the promizing potassium bronze K0,5V2O5, ε'-V2O5, as well as a lamellar manganese oxide: the sol-gel birnessite and its doped cobalt form. The structure-electrochemistry relationships are clarified through a study combining electrochemical properties, X-ray diffraction and Raman spectroscopy of materials at different insertion rate, end of the reaction and after galvanostatic cycling. New phases are highlighted and specific capacities between 100 and 160 mAh / g in the field of 4V-1V potential can be obtained with sometimes remarkably stable as in the case of NaV2O5 and ε'-V2O5

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Desai, Parth. « Achieving Na-ion Battery Advancements Through Decoding Degradation Pathways and Electrolyte Engineering ». Electronic Thesis or Diss., Sorbonne université, 2023. http://www.theses.fr/2023SORUS681.

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La dépendance croissante à l’égard des batteries lithium-ion pour le stockage de l’énergie nécessite l’exploration de produits chimiques alternatifs en raison des ressources limitées et géopolitiquement sensibles en lithium. La batterie sodium-ion, est considérée comme une alternative prometteuse, avec d’abondants précurseurs de sodium. Après une analyse comparative des paramètres critiques, la chimie Na3V2(PO4)2F3(NVPF)|hard carbon(HC) a été sélectionnée pour cette étude, de par la durabilité structurelle du matériau NVPF, ses performances énergétiques robustes et sa stabilité air/eau. Cette thèse explore de manière exhaustive cette technologie en étudiant les mécanismes de dégradation, en améliorant les performances des piles boutons à l'échelle du laboratoire et en transférant les résultats aux cellules 18650 commerciales. Dans un premier temps, les instabilités des matériaux NVPF ont été examinées, avec des températures élevées provoquant la dissolution du vanadium, conduisant à une dégradation de l'électrode NVPF, à une instabilité de l'électrolyte et enfin à une contamination de l'électrode HC. Les co-sels d'imide et le revêtement de carbone uniforme atténuent la dissolution du vanadium mais ne parviennent pas à supprimer les réactions électrolytiques indésirables. Par conséquent, les électrolytes Gen-3 méticuleusement conçus avec des additifs améliorent le cycle et la durée de vie des cellules à des températures élevées sans dégagement gazeux excessif. Un cosolvant d'acétate de méthyle à faible viscosité a été infusé dans l'électrolyte pour améliorer encore plus la puissance et les performances à basse température. L'électrolyte optimisé présente une durée de vie, des performances en Crate, une tolérance de température étendue et une sécurité remarquables, ce qui le rend adapté à une possible commercialisation. La thèse se termine par l'évaluation de la stabilité à 0 V des batteries sodium-ion, la compréhension des mécanismes de décomposition du SEI et la proposition de solution pour y pallier. Enfin, des orientations futures sont décrites pour propulser le développement des batteries Na-ion et remettre en question la technologie Li-ion basée sur LiFePO4
The growing dependence on lithium-ion batteries for energy storage necessitates the exploration of alternative chemistries due to the limited and geopolitically sensitive lithium resources. The sodium-ion battery, considered a sustainable complement with abundant sodium precursors, is swiftly progressing towards commercialization. Following a comparative analysis of critical parameters, the Na3V2(PO4)2F3(NVPF)|hard carbon(HC) chemistry was selected for NVPF material's structural durability, robust power performance, and air/water stability. This thesis comprehensively navigates this technology by investigating degradation mechanisms, improving performance in lab-scale coin cells, and seamlessly transferring findings to commercial 18650 cells. At first, NVPF material instabilities were examined, with elevated temperatures causing vanadium dissolution, leading to NVPF electrode degradation, electrolyte instability, and finally, contamination of HC electrode. Imide co-salts and uniform carbon coating mitigate vanadium dissolution yet fail to suppress undesired electrolyte reactions. Hence, meticulously designed Gen-3 electrolytes with additives enhance cells' cycle and calendar life at elevated temperatures without excessive gassing. A low-viscosity methyl acetate cosolvent was infused in the electrolyte to enhance power and low-temperature performance further. The optimized electrolyte demonstrates remarkable cycle life, rate performance, extensive temperature tolerance, and safety, making it suitable for evaluation in commercial scenarios. The thesis concludes with assessing the 0V stability of sodium-ion batteries, comprehending SEI decomposition mechanisms, and proposing remedies. Lastly, future directions are outlined to propel Na-ion battery development and challenge LiFePO4-based Li-ion technology

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GENTILE, ANTONIO. « MXene-based materials for alkaline-ion batteries : synthesis, properties, applications ». Doctoral thesis, Università degli Studi di Milano-Bicocca, 2022. http://hdl.handle.net/10281/382748.

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La produzione sempre maggiore di dispositivi portatili e auto elettriche chiede al mercato di produrre dispositivi efficienti in grado di poter accumulare l’energia elettrica. Per questo tipo di tecnologie in cui la miniaturizzazione del dispositivo è essenziale, le batterie litio ione (LIBs) sono diventate il mezzo di accumulare energia. La ricerca su queste batterie è focalizzata ad ottenere dispositivi sempre più performanti con materiali elettrodici ad alte capacità gravimetriche e volumetriche. Accanto all’aspetto tecnologico, legato alla ottimizzazione dei materiali, vi è anche quello dell’approvvigionamento dei componenti attivi della batteria, tra tutti il litio. La problematica attualmente è affrontata studiando batterie con altri metalli alcalini (Na e K). Di questi dispositivi non esistono però materiali già standardizzati malgrado la ricerca, specialmente sulle batterie sodio ione (SIB), sia partita solo qualche anno più tardi rispetto quella delle LIB; per cui queste tecnologie oggi sono destinate ad affiancare quelle delle LIB per sopperire all’enorme richiesta di mercato di batterie per i veicoli del futuro. L’obbiettivo del presente lavoro è stato quello di sviluppare materiali anodici a base di MXene per ottenere efficienti anodi per batterie sodio e litio ione. I MXenes sono una famiglia di carburi di metalli di transizione con una struttura 2D che sembrerebbe promettente per l’intercalazione di diversi ioni grazie ad una grande flessibilità ed adattabilità strutturale nei confronti del tipo di ione intercalante. L’intercalazione degli ioni avviene con un meccanismo pseudocapacitivo per cui i materiali hanno capacità limitate, ma hanno grande stabilità elettrochimica su migliaia di cicli ed efficienze coulombiche prossime al 100%. La produzione di questo materiale avviene per etching in HF di un precursore chiamato MAX phase. Questo è il metodo più facile e veloce per ottenere il materiale in scala di laboratorio ma presenta numerose criticità quando i volumi vengono rapportati su scala industriale. Una gran parte del lavoro è stata dedicata allo studio della tecnica sintetica per ottenere MXenes per SIB riducendo o sostituendo HF nella sintesi chimica. I materiali sono stati caratterizzati con varie tecniche di caratterizzazioni strutturali, morfologiche ed elettrochimiche. Data la struttura 2D, che ricorda quella del grafene, un uso frequente in letteratura è quello della realizzazioni di nanocompositi per SIB e LIB, al fine di produrre materiali ad alta capacità, come richiesto nel mercato delle batterie. Sono stati quindi ottenuti dei nanocompositi a base di antimonio-MXene e ossido di stagno-MXene testati rispettivamente in SIB e LIB. Antimonio e ossido di stagno sono due materiale dalla elevata capacità teorica, quando usati come anodi in batterie, ma allo stesso tempo sono estremamente fragili e tendono a polverizzarsi nei processi di carica e scarica. Il MXene è servito da buffer per limitare o evitare la frattura e distacco delle leghe dalla superficie elettrodica
The ever-increasing production of portable devices and electric cars asks to the market to produce efficient devices that can store electrical energy. For these types of technologies, where device miniaturization is essential, lithium-ion batteries (LIBs) have become leaders as energy storage systems. The research on the lithium-ion batteries is focused to obtain more performing devices with high gravimetric and volumetric capacities of the electrode materials. In addition to the technological aspect, related to the optimization of materials, there is the supply chain of active components of the battery to consider, starting from lithium. At the moment, the problem is tackled by studying batteries with other alkaline metal ions, i.e. Na+ and K+. However, there are no standardized active materials for these devices, especially on sodium-ion batteries (SIBs), started only a few years later than that of LIBs; therefore, today these technologies are intended to support the LIBs in order to satisfy the enormous market demand of the batteries for the future vehicles. The goal of this work was to develop MXene-based anode materials to obtain efficient anodes for sodium and lithium-ion batteries. MXenes are a family of inorganic transition metal carbides, nitrides, and carbonitrides with a 2D structure that would seem promising for the intercalation of different ions due to a great flexibility and adaptability towards several intercalating ions. The ion intercalations occur by a pseudocapacitive mechanism whereby the materials have limited capacity, but they have great electrochemical stability over thousands of cycles and coulombic efficiencies near to 100%. The production of this material was done by HF etching of a precursor called MAX phase. This is the easiest and fastest method to obtain the material in laboratory scale, but it has many criticalities when the process has to be scale-up to industrial scale. A large part of this work was spent studying the synthetic technique to obtain MXenes for SIB by reducing or replacing HF in the chemical synthesis. The materials have been characterized by various techniques such as X-ray diffractometry, electron microscopy, X-ray photoelectron spectroscopy, etc., and by electrochemical tests, such as cyclic voltammetry and galvanostatic cycling. Thanks to the 2D structure, a common use of MXene in the literature is in nanocomposite syntheses for SIBs and LIBs, in order to produce high-capacity materials, as required in the battery market. Therefore, two nanocomposites based on antimony-MXene and tin oxide-MXene tested for SIB and for LIB respectively, were synthesized. Antimony and tin oxide are two materials with high theoretical capacity when used as anodes in batteries, but at the same time, they are extremely fragile and tend to pulverize during charging and discharging processes. MXene is used as a buffer to limit or prevent cracking and separation of alloys from the electrode surface.

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Difi, Siham. « Phosphates de type NASICON comme matériaux d'électrode pour batteries sodium-ion à haute densité d'énergie ». Thesis, Montpellier, 2016. http://www.theses.fr/2016MONTT212/document.

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Ce mémoire est consacré à l’étude des composites à base de phosphates de type NASICON comme matériaux d’électrode pour batteries sodium-ion : Na1+xFexTi2-x(PO4)3/C et Na1+xFexSn2-x(PO4)3/C avec 0 ≤ x ≤ 1. Ces composites ont été synthétisés par voie solide suivie d’une pyrolyse avec le saccharose. Ils sont constitués de particules ayant une porosité élevée et enrobées par du carbone conférant à l’électrode une bonne conductivité ionique et électronique. Les mécanismes réactionnels se produisant lors des cycles de charge-décharge ont été analysés en mode operando par diffraction des rayons X, spectroscopies Mössbauer du 57Fe et de 119Sn et spectroscopie d’absorption X. Pour les composites fer-titane, ces mécanismes sont essentiellement basés sur la diffusion des ions Na+ dans les canaux des phases cristallisées avec changements d’état d’oxydation des métaux. Pour les composites fer-étain, les mécanismes sont plus complexes incluant insertion, conversion conduisant à la destruction des phases NASICON, puis formation d’alliages NaxSn. Les meilleures performances électrochimiques ont été obtenues pour Na1,5Fe0,5Ti1,5(PO4)3/C avec un potentiel de fonctionnement de 2,2 V vs Na+/Na0. Même si ces deux familles de matériaux peuvent être utilisées à plus bas potentiel, les performances doivent être améliorées pour envisager leur application comme électrode négative
This thesis is devoted to the study of phosphate based composites with NASICON type structure, that are used as electrode materials for sodium-ion batteries: Na1+xFexTi2-x (PO4)3/C et Na1+xFexSn2-x(PO4)3/C with 0 ≤ x ≤ 1. These composites were synthesized by solid state route followed by a pyrolysis reaction with sucrose. They consist of particles having high porosity and coated with carbon giving to the electrode good ionic and electronic conductivity. The reaction mechanisms occurring during charge-discharge cycles were analyzed in operando mode, by X-ray diffraction, 57Fe and 119Sn Mössbauer spectroscopies and X-ray absorption spectroscopy. For the iron-titanium composites, the mechanisms are essentially based on the diffusion of Na+ in the channels of the crystalline phases with changes of transition metal oxidation state. For iron-tin composites, the mechanisms are more complex including insertion, conversion leading to the destruction of the NASICON phases and then reversible formation of NaxSn alloys. The best electrochemical performances were obtained for Na1,5Fe0,5Ti1,5(PO4)3/C with an operating potential of 2.2 V vs. Na+/Na0. Although these two types of materials can be used at lower potential, the performances must be improved to consider their application as the negative electrode

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Beuvier, Thomas. « Des nanotitanates de sodium aux dioxydes de titane : électrode négative à base de TiO2(B) nanométrique pour accumulateur lithium-ion ». Phd thesis, Université de Nantes, 2009. http://tel.archives-ouvertes.fr/tel-00454406.

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Le dioxyde de titane, connu pour ses applications dans les domaines de la photoactivité et du photovoltaïque, est aussi un candidat d'électrode négative pour batteries lithium-ion. Les variétés anatase et TiO2(B) sont les plus prometteuses. Leurs capacités sont respectivement de 0,50 et 0,75 Li+ par motif de TiO2. Sous forme nanométrique, elles présentent des densités d'énergie et de puissance accrues. L'objet de ce travail de thèse concerne la synthèse par chimie douce de dioxydes de titane nanométriques selon la méthode développée initialement par Kasuga et al. et leur caractérisation. La méthode en trois étapes génère successivement deux intermédiaires tels que (i) le titanate (NaOH)xTiO2(H2O)y (x = 0,3-0,5 et y = 0,4-0,7) par reflux, et (ii) l'acide titanique TiO2(H2O)z (z = 0,7-0,8) après échange ionique, et finalement, après recuit, (iii) le TiO2 de morphologie proche de celle du titanate précurseur. Quatre titanates de sodium ont été identifiés, trois structures lamellaires, se différenciant par leur morphologie (nanotubes, semi-nanotubes et nanorubans) et une structure amorphe s'apparentant à des nanosphères. Après échange ionique et recuit, les nanotubes et les nanosphères se transforment en anatase, les semi-nanotubes en un mélange d'anatase et de TiO2(B), et les nanorubans en TiO2(B) exclusivement. La quantification par spectroscopie Raman du ratio anatase/TiO2(B) a été développée en calibrant les intensités avec les résultats d'électrochimie. Enfin, les nanorubans de TiO2(B) ont été testés au sein de demi-batterie lithium métal. Les performances sont prometteuses avec une capacité réversible de 200 mAh.g-1 à C/3 (soit 0,6 Li+ par TiO2) et de 100 mAh.g-1 à 15C.

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Fang, Runhe. « Effect of composition and morphology on the electrochemical performance of Na3V2(PO4)2F3/Na3V2(PO4)2FO2 ». Electronic Thesis or Diss., Sorbonne université, 2022. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2022SORUS001.pdf.

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Dans le système de batterie à ions sodium (SIB), l'électrode positive joue un rôle important. Bien que plus faibles que les matériaux d'oxyde lamellaire sous certains aspects, comme la conductivité électrique, les matériaux polyanioniques sont devenus l'une des deux principales catégories de matériaux d'électrode positive grâce à leur excellente stabilité électrochimique et leur tension de fonctionnement élevée. La famille Na3V2(PO4)2F3-yOy (0 ≤ y ≤ 2) est notamment la plus remarquable en termes de performances électrochimiques. Cependant, les performances électrochimiques sont limitées en raison de la conductivité électronique plutôt faible induite par les unités de vanadium bi-octaèdre isolées au sein de la structure. De nombreuses études ont été menées pour améliorer les propriétés électrochimiques du Na3V2(PO4)2F3-yOy au moyen d'un revêtement de carbone et d'une morphologie spéciale, etc. Cependant, des améliorations inconscientes dans de multiples aspects peuvent conduire à négliger la compréhension d'un élément spécifique modifié, en raison de l'amélioration finale des performances électrochimiques. Par conséquent, cette thèse de doctorat consiste à bien contrôler toutes les variétés et à comparer l'impact de la morphologie et de la composition de Na3V2(PO4)2F3-yOy afin d'améliorer ses performances électrochimiques finales dans une perspective plus fondamentale. Ainsi, ce travail est composé des parties suivantes sous forme d'articles déposés. Dans le premier chapitre, qui constitue un état de l'art, le contexte du développement des batteries et en particulier des SIBs sera brièvement présenté. Les matériaux communs pour chaque partie différente de SIBs seront décrits plus en détail. Ensuite, l'attention sera portée sur le Na3V2(PO4)2F3-yOy et l'état actuel de ses recherches sera présenté en détail en termes de structure cristalline et de synthèse, etc. Ensuite, dans le deuxième chapitre, une série de synthèses légèrement ajustées avec les mêmes précurseurs a été réalisée pour obtenir des particules de Na3V2(PO4)2F3-yOy de différentes morphologies et de composition similaire, puis pour étudier l'effet des morphologies sur les performances de stockage d'énergie. Dans le chapitre III, à partir de la morphologie la plus performante trouvée dans le deuxième chapitre, l'effet de la teneur en oxygène sur les propriétés de transport et la performance électrochimique dans Na3V2(PO4)2F3-yOy (différents pourcentages de substitution de O2-) a été étudié, tout en gardant les morphologies inchangées. Dans le chapitre IV, les Na3V2(PO4)2FO2 trouvés dans le chapitre III ont été comparés avec ceux synthétisés par différentes méthodes avec la même composition de particules mais des morphologies et une fonctionnalisation de surface totalement différentes afin de mieux comprendre l'impact de la morphologie et du revêtement de surface sur la capacité de stockage d'énergie.Enfin, le solvant eutectique profond, un type de liquide ionique, a été utilisé comme nouveau moyen de synthèse pour atteindre une morphologie totalement nouvelle et spéciale qui n'avait pas été signalée auparavant et une nouvelle approche pour fabriquer un revêtement de carbone. En général, les différentes morphologies et compositions de Na3V2(PO4)2F3-yOy sont obtenues séparément en contrôlant et en affinant une série de méthodes de synthèse. Leurs influences sur l'électrochimie finale du matériau ont également été étudiées séparément. Ces études contribuent à la compréhension de ce matériau d'un point de vue fondamental, facilitant ainsi son optimisation ultérieure
In the sodium ion battery system, the positive electrode plays an important role. Although weaker than layered oxide materials in some aspects, such as electrical conductivity, polyanionic materials have become one of the two main categories of positive electrode materials with their excellent electrochemical stability and high operating voltage. Na3V2(PO4)2F3-yOy (0≤y≤2) family is especially the most outstanding in terms of electrochemical performance. However, the electrochemical performance is limited because of the rather poor electronic conductivity induced by the isolated vanadium bi-octahedra units within the structure. There have been many studies to improve the electrochemical properties of Na3V2(PO4)2F3-yOy by means of carbon coating and special morphology etc. However, unconscious improvements in multiple aspects can lead to neglected further understanding of one specific changed element, due to the ultimately electrochemical performance enhancements. Therefore, this PhD thesis is consistent of well controlling all the varieties and comparing the morphology and composition impact of Na3V2(PO4)2F3-yOy without any carbon coating in order to improve its final electrochemical performance through a more fundamental perspective. Thus, this work is composed of the next parts under the form of deposited articles. In the first chapter, which is a state of the art, the background of the development of batteries and especially the sodium ion batteries will be briefly introduced. The common materials for each different part of the sodium ion battery will be further described. Next, attention will be focused on Na3V2(PO4)2F3-yOy and show the current status of its research in detail in terms of crystal structure and synthesis, etc. Then in the second chapter, a series of slightly tuned synthesis with the same precursors were carried out to obtain the Na3V2(PO4)2F3-yOy particles with different morphologies and similar composition and then investigate the effect of morphologies on energy storage performance. In the subsequent chapter III, from one most performant morphology found in the second chapter, the effect of the oxygen content on transport properties and electrochemical performance within Na3V2(PO4)2F3-yOy (different O2- substitution percent) were investigated, while keeping the morphologies unchanged. In the next chapter IV, the Na3V2(PO4)2FO2 found in chapter III with those synthesized through different methods with the same particle composition but totally different morphologies and surface functionalization were compared to further understand the morphology and surface coating impact on the energy storage capacity. At last, deep eutectic solvent, one kind of ionic liquid, was used as a new synthesis medium to reach a totally new and special morphology does not reported before and a new approach to make a carbon coating. In general, the different morphologies and compositions of Na3V2(PO4)2F3-yOy are obtained separately by controlling and refining a series of synthesis methods. Their influences on the final electrochemistry of the material have also been investigated separately. These studies contribute to the understanding of this material from a fundamental point of view, thus facilitating further optimization

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Adelhelm, Philipp. « From Lithium-Ion to Sodium-Ion Batteries ». Diffusion fundamentals 21 (2014) 5, S.1, 2014. https://ul.qucosa.de/id/qucosa%3A32397.

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Nwafornso, Tochukwu. « Bismuth anode for sodium-ion batteries ». Thesis, Uppsala universitet, Strukturkemi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-449075.

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It is imperative to develop alternative battery technologies based on naturally abundant elements, with competitive performance as lithium-ion batteries. Sodium has a natural abundance 1000 times more than lithium with both lithium and sodium-ion batteries having similar chemistry. Sodium-ion batteries are potentially an alternative that can achieve such competitive performance, given that electrode and electrolyte materials of high rate and long-term electrochemical performance are being developed. This thesis investigates the rate capability and long-term performance of bulk bismuth electrodes containing varying carbon content. The electrodes were cycled in cells with glyme-based electrolytes: diglyme and tetraglyme. Scanning electron microscopy and energy dispersive spectroscopy showed the morphology and elemental mapping of pristine and cycled bismuth electrodes. The result demonstrates the evolving porosity as the electrode cycled. The galvanostatic cycling of half-cells showed two plateaus each for sodiation and desodiation. Also, two peaks are seen in cyclic voltammetry suggesting a two-phase reaction. When cycled between -0.6 to 0.6 V in a symmetrical cell, the bismuth electrode showed an appreciable rate capability at a current rate of 770 mA/g in diglyme. In tetraglyme, it showed a poor rate capability, even at a current rate of 308 mA/g. The rate performance in a full cell cycled between 0.1 to 3.2 V also showed a good rate capability at a current rate of 770 mA/g in diglyme. Tetraglyme showed poor rate capability at the same current rate. The capacity retention was higher in the symmetrical cells, with 79 % and 78 % capacity retention relative to the initial charge capacity after 100 cycles for diglyme and tetraglyme. At the same current rate and more than 70 cycles, the full cells showed capacity retention of 58 % in diglyme and 44.8 % in tetraglyme. The capacity retention varied slightly for the two different electrode composites. The superior performance in the symmetrical cell is due to the narrow voltage window. Evaluating the stability of the solid electrolyte interphase via galvanostatic cycling suggests some stability issues. The full cells showed growing resistance with an increasing number of cycles.

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Simone, Virginie. « Développement d'accumulateurs sodium-ion ». Thesis, Université Grenoble Alpes (ComUE), 2016. http://www.theses.fr/2016GREAI092/document.

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Au vu d’une demande croissante pour un stockage d’énergie à grande échelle, il est préférable de se tourner vers des matériaux peu coûteux et répandus. De ce point de vue, le sodium, qui présente des caractéristiques très proches de celles du lithium, présente également l’avantage d’être peu coûteux, abondant et réparti uniformément dans le monde. Cette thèse porte sur l’étude d’un système complet Na-ion constitué d’un carbone dur à l’électrode négative et d’un oxyde lamellaire à l’électrode positive. Un volet sur l’électrolyte a également été abordé.Concernant l’électrode négative, l’influence de la température de pyrolyse de la cellulose sur la structure des carbones durs et sur les performances électrochimiques a été étudiée. Une graphitisation localisée, une fermeture des pores et une évolution de la porosité interne avec la température de pyrolyse ont pu être observées. Les meilleures performances électrochimiques ont été obtenues pour le matériau synthétisé à 1600 °C : une capacité réversible d’environ 300 mAh.g-1 stable sur 200 cycles est atteinte à 37,2 mA.g-1 avec une efficacité coulombique initiale de 84 %. Pour mieux comprendre les mécanismes d’insertion du sodium dans ces matériaux, des études par spectroscopie d’impédance, SAXS et EDX ont été réalisées sur des carbones durs cyclés à différents potentiels.Le matériau d’électrode positive choisi est l’oxyde lamellaire Na0,6Ni0,25Mn0,75O2. L’influence de la température de calcination a permis de faire varier le nombre de défauts d’empilement de type P3 au profit d’une phase P2 plus cristalline. Après avoir optimisé l’électrolyte à base de carbonates pour garantir la reproductibilité des tests oxyde lamellaire//sodium métal, une capacité d’oxydation de 130 mAh.g-1 a pu être atteinte au premier cycle avant de chuter fortement sur les 40 cycles suivants. Cette perte de capacité a pu être en partie expliquée par des études de DRX operando. Enfin, ces travaux ont permis d’aboutir à des systèmes complets Na-ion dont les premiers résultats sont prometteurs
Because of the development of renewable energy and electric vehicles, the need for a large scale energy storage has increased. This type of storage requires a large amount of raw materials. Therefore low cost and abundant resources are necessary. Consequently the use of sodium batteries is of interest because sodium’s low cost, high abundance, and worldwide availability. This PhD thesis deals with the study of a full Na-ion cell containing a hard carbon negative electrode, and a layered oxide positive electrode. A shorter part concerns the electrolyte.Concerning the negative electrode, the first objective was to understand in detail the influence of the pyrolysis temperature of a hard carbon precursor, cellulose, on the final structure of the material and its consequences on the electrochemical performance. Many techniques were used to characterize the hard carbon structure as a function of the pyrolysis temperature. Localized graphitization, pore closure, and an increase in micropore size have been observed with increasing temperature. The best electrochemical performance has been reached with the hard carbon synthesized at 1600°C: a reversible capacity of around 300 mAh.g-1 stable over 200 cycles is obtained at 37.2 mA.g-1 with an initial coulombic efficiency of 84%. To deeper understand sodium insertion mechanisms in hard carbon structures impedance spectroscopy, SAXS and EDX were carried out on hard carbon electrodes cycled at different voltages.The layered oxide Na0.6Ni0.25Mn0.75O2 was investigated as the positive electrode. It was observed that with increasing calcination temperature the number of P3-type stacking faults decreases in favor of a more crystalline P2 phase. Then, the carbonate-based electrolyte has been optimized to guarantee the reproducibility of the electrochemical tests performed in a layered oxide//sodium metal configuration. A first oxidation capacity of around 130 mAh.g-1 is reached. However this value drops quickly after 40 cycles. Operando XRD analysis did partially explain the capacity decrease. Finally, the results of these investigations were used to design an optimized full cell which demonstrated promising performance during initial testing

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LONGONI, GIANLUCA. « Investigation of Sodium-ion Battery Materials ». Doctoral thesis, Università degli Studi di Milano-Bicocca, 2017. http://hdl.handle.net/10281/153278.

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La tecnologia delle batterie Sodio-ione ha negli ultimi tempi suscitato una crescente attenzione da parte della comunità scientifica mondiale grazie al fatto di poter rappresentare una valida alternativa alla tecnologia Litio-ione, più sostenibile dal punto di vista ambientale ed economico. Il lavoro di Dottorato è stato principalmente dedicato alla ricerca di materiali attivi per batterie Sodio ione. I materiali presi in considerazione, sia catodici che anodici, sono stati indagati ponendo particolare attenzione ai limiti e difficolta pratiche che gli stessi possono manifestare nei confronti dell'intercalazione di sodio. Tra questi sono stati considerati: i) la valutazione della diffusione di Na+ in una struttura host intercalante, ii) e prodotti, gli intermedi e la reversibilità di reazione di conversione di ossidi dei metalli di transizione, iii) gli effetti delle proprietà cristalline dei materiali sulle performance elettrochimiche e iv) le caratteristiche chimico-fisiche caratterizzanti la generale stabilità di un materiale funzionale per batterie. Durante il lavoro di tesi è stato perpetrato un continuo parallelismo tra le caratteristiche morfologiche e strutturali e le performance elettrochimiche, ottenendo infine una dettagliata visione di molteplici classi di materiali attivi per sodio-ione. Ciò ha reso necessario un approccio inter-disciplinare in cui ad avanzate tecniche analitiche di tipo elettrochimico, è stato affiancato un approccio più specificatamente ingegneristico dei materiali stessi, al fine di evidenziare le correlazione proprietà-struttura. Tra le classi di materiali attivi investigate un ruolo di primaria importanza è stato riservato a materiali ad intercalazione catodici e materiali a conversione basati su ossidi di metalli di transizione. I primi, tipicamente materiali con struttura cristallina lamellare di natura ossidica, o a base di fosfati e pirofosfati, promuovono l’intercalazione di sodio con cinetiche veloci e con molteplici geometrie e pattern assunti dai cationi intercalati. I materiali a conversione invece permettono di ottenere lo stoccaggio energetico tramite reazione chimiche spontanee che avvengono tra materiale attivo e lo ione sodio. Paragonati a materiali ad intercalazione, i materiali a conversione presentano molteplici problematiche, tra cui: i) la variazione di volume considerevole che accompagna la reazione di conversione che introduce stress meccanici considerevoli e porta alle tipiche frammentazioni d’elettrodo e ii) processi irreversibili che solitamente corredano la reazione di conversione. Un aspetto che rende tali materiali meritevoli di essere studiati è la loro capacità di stoccare elevate quantità di sodio rendendoli capaci di capacità specifiche teoriche straordinarie (> 800 mAh/g). Tutti questi aspetti sono stati affrontati e tenuti in profonda considerazione al fine di mettere a punto un materiali a conversione anodica nano-strutturato a base di Co3O4 che rappresentasse una valida soluzione al problema di perfezionamento delle batterie sodio-ione. Assieme a materiali anodici, è stato altresì condotto lo studio di materiali catodici caratterizzati da elevate performance ma bassi costi di sintesi. Lo studio preliminare del composito ad intercalazione Na2FeP2O7/MWCNT a condotto ad interessanti risultati legati ad estremamente veloci cinetiche di diffusione di sodio all’interno del network di canali del materiale e ad una generale stabilità durante la ciclazione. All’anatasio (TiO2) nano-crystallino sintetizzato ad-hoc è stata dedicata l’ultima parte del lavoro di ricerca. Tale lavoro ha permesso di confermare importanti correlazioni tra le caratteristiche cristalline superficiali dei nano-cristalli e i meccanismi di interazione con sodio attraverso meccanismi pseudocapacitivi; e significativi avanzamenti sono stati ottenuti nella definizione di tale meccanismo e nella messa a punto di un efficiente materiale anodico a basso costo.
Na-ion battery technology has recently aroused great interest among all the scientific community, as a valid and more environmentally friendly alternative to Li-ion batteries. The PhD research activity has been mostly devoted to the investigation of reliable active materials for sodium ion battery technology. All the investigated materials, either anode or cathode, have been investigated trying to highlight the major limits and difficulties connected to sodium intercalation and conversion reactions. Among these, some are: i)assessment of Na diffusion in an intercalating host structure, ii)products and reversibility of transition metal oxides conversion reactions, iii) effects of materials crystalline properties on electrochemical performances and iv) features influencing the overall stability of a functional material. In order to keep the most broad-based overview of the problem, it has been chosen to systematically start, for each species electrochemically investigated, from its synthesis and thorough chemical-physical characterization. Rather than a pure electrochemical analysis, a continuous parallelism between morphological features, structural characteristics and performances was encouraged, eventually obtaining a detailed overlook of different classes of active materials for sodium batteries. What has been screened all along the three year-long research period has been a comprehensive investigation of new generation electrochemically active materials for energy storage applications. This implied an inter-disciplinary work in which advanced electro-analytical techniques have been widely used to characterize inorganic compounds or ad-hoc synthesized composites keeping in mind precise structure-performance correlations. Among the investigated classes, a role of relevance has been reserved to intercalating cathode species and conversion anode materials. The former, typically layered transition metal oxides, phosphates and pyrophosphates, are capable of sodium cations insertion, with fast kinetics, between layers or inside channels generated from peculiar atoms arrangement. Conversion anode materials on the other hand, carries out the sodium storage via spontaneous chemical reactions with oxide-based material, such as Co3O4 or Fe2O3, a chalcogenide or a halide. Compared to intercalation materials, conversion ones are more challenging to deal with, due to the following difficulties: i)their not negligible volume change during conversion reaction and the correlated induced mechanical stresses leading to electrode fracturing and pulverization, ii)occurrence of irreversible and parasitic reactions and iii)material operating potentials is often too high (around 1.0 V vs. Na/Na+) and thus not suitable for being used as anode materials inside a sodium cell. A positive feature that makes these material worthy to be studied is the high sodium uptake they are able to bare, bestowing them high theoretical specific capacities (>800 mAh∙g-1). All these aspects have been tackled in designing a conversion anode that might constitute a valid solution toward a sodium secondary battery whole-cell assembly. Together with anode materials also a high-performing and low-cost cathode material has been investigated. The exploratory study of pyrophosphate-MWCNT composite intercalation material led to interesting results referred to fast kinetics and material reliability throughout the cycles. To TiO2 nanocrystals synthesis and crystalline appearance-electrochemical properties correlation has beeb dedicated an exhaustive analysis which allowed to achieve significative advancements in defining the sodium uptake mechanism for pseudo-capacitive oxide-based anode material for sodium-ion batteries.

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Nose, Masafumi. « Studies on Sodium-containing Transition Metal Phosphates for Sodium-ion Batteries ». 京都大学 (Kyoto University), 2016. http://hdl.handle.net/2433/215565.

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Naqash, Sahir Verfasser], Olivier [Akademischer Betreuer] Guillon et Jochen M. [Akademischer Betreuer] [Schneider. « Sodium ion conducting ceramics for sodium ion batteries / Sahir Naqash ; Olivier Guillon, Jochen Michael Schneider ». Aachen : Universitätsbibliothek der RWTH Aachen, 2019. http://d-nb.info/1190040611/34.

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Naqash, Sahir [Verfasser], Olivier Akademischer Betreuer] Guillon et Jochen M. [Akademischer Betreuer] [Schneider. « Sodium ion conducting ceramics for sodium ion batteries / Sahir Naqash ; Olivier Guillon, Jochen Michael Schneider ». Aachen : Universitätsbibliothek der RWTH Aachen, 2019. http://nbn-resolving.de/urn:nbn:de:101:1-2019070807164971884045.

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Toigo, Christina Verena <1986&gt. « Towards eco-friendly batteries : concepts for lithium and sodium ion batteries ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2022. http://amsdottorato.unibo.it/10067/1/Thesis%20CT_final.pdf.

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Several possibilities are arising aiming the development of “greener”, more sustainable energy storage systems. One point is the completely water-based processing of battery electrodes, thus being able to renounce the use of toxic solvents in the preparation process. Despite its advantage of lower cost and eco-friendlyness, there is the need of similar mechanical and electrochemichal behavior for boosting this preparation mode. Another point – accompanying the water-based processing - is the replacement of solvent-based polymer binders by water-based ones. These binders can be based on fluorinated, crude-oil based polymers on the one side, but also on naturally abundant and economic friendly biopolymers. The most common anode materials, graphite and lithium titanate (LTO), have been subjected a water-based preparation route with different binder systems. LTO is a promising anode material for lithium ion batteries (LIBs), as it shows excellent safety characteristics, does not form a significant SEI and its volume change upon intercalation of lithium ions is negligible. Unfortunately, this material suffers from a rather low electric conductivity - that is why an intensive study on improved current collector surfaces for LTO electrodes was performed. In order to go one step ahead towards sustainable energy storage, anode and cathode active materials for a sodium ion battery were synthesized. Anode active material resulted in a successful product which was then subjected to further electrochemical tests. In this PhD work the development of “greener” energy storage possibilities is tested under several aspects. The ecological impact of raw materials and required battery components is examined in detail.

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Wu, Di Ph D. Massachusetts Institute of Technology. « A layered sodium titanate as promising anode material for sodium ion batteries ». Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/93004.

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Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2014.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 58-60).
Sodium ion batteries have recently received great attention for large-scale energy applications because of the abundance and low cost of sodium source. Although some cathode materials with desirable electrochemical properties have been proposed, it's quite challenging to develop suitable anode materials with high energy density and good cyclability for sodium ion batteries. Herein, we report a layered material, 03-NaTiO2, that delivers 130mAhg-1 of reversible capacity and presents excellent cyclability with capacity retention over 97.5% after 40 cycles and high rate capability. Furthermore, by coupling the electrochemical process with in situ X-ray diffraction, the structure evolution and variation of cell parameters corresponding to an 03-03' phase transition during sodium deintercalation is investigated. Unusual lattice parameter variation was observed by in situ XRD, which can be related to the structure modulation with varying Na vacancy ordering. An irreversible structural modification upon overcharging is also confirmed by in situ XRD. In summary, our work demonstrates that 03-NaTiO2 is a very promising anode material for sodium ion batteries with high energy density.
by Di Wu.
S.M.

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Cesetti, Lorenzo. « Systematic study of in-situ sodium plating/stripping on anode free substrates for sodium ion batteries ». Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.

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Gli oggetti di studio di questo lavoro di tesi sono le batterie agli ioni-sodio, in particolare una loro variante ancora in fase di sviluppo denominata “anode-free”. Seppur questi accumulatori al sodio non siano nuovi ma conosciuti da tempo, è solamente dal 2010 che gli studi al riguardo si sono intensificati, tanto da portare alla realizzazione di diversi prototipi in pochi anni. Le maggiori difficoltà nel loro sviluppo sono state riscontrate nella scelta del materiale costituente l’anodo. Per ovviare al problema sono state ideate le batterie agli ioni-sodio “anode-free”: l’anodo è rappresentato da un semplice collettore di corrente, generalmente alluminio o rame, dove gli ioni-sodio si depositano, riducendosi e formando sodio metallico in situ durante la carica; al contrario, durante la scarica, è il sodio metallico che si ossida tornando ione e migrando verso il catodo. Il lavoro di tesi ivi proposto è stato sviluppato presso l’Energy Storage Group del College of Engineering della Swansea University di Swansea (UK). Sono stati esaminati tre substrati differenti valutando l’idoneità di ciascuno di essi ad un’applicazione come anodo in un accumulatore agli ioni-sodio “anode-free”, attraverso tecniche di caratterizzazione standard quali Galvanostatic Cycling (GC), Cyclic Voltammetry (CV) ed analisi al microscopio. I materiali presi in esame sono stati: acciaio inossidabile, acciaio inossidabile rivestito di nichel ed un substrato di nichel chiamato nichel foam. Dopo aver visto che l’acciaio inossidabile è il substrato in grado di garantire prestazioni migliori, lo step successivo è stato quello di realizzare una vera e propria batteria agli ioni-sodio “anode-free” utilizzando un catodo composto da pirite presodiata. Le performance della batteria proposta in questa tesi sono state infine confrontate con quelle di un modello di riferimento che impiega un collettore di corrente in alluminio rivestito da carbon black come anodo.

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Toumar, Alexandra Jeanne. « Phase transformations in layered electrode materials for sodium ion batteries ». Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/111255.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Materials Science and Engineering, 2017.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages 118-130).
In this thesis, I investigate sodium ion intercalation in layered electrode materials for sodium ion batteries. Layered metal oxides have been at the forefront of rechargeable lithium ion battery technology for decades, and are currently the state of the art materials for sodium ion battery cathodes in line for commercialization. Sodium ion intercalated layered oxides exist in several different host phases depending on sodium content and temperature at synthesis. Unlike their lithium ion counterparts, seven first row layered TM oxides can intercalate Na ions reversibly. Their voltage curves indicate significant and numerous reversible phase transformations during electrochemical cycling. These transformations arise from Na-ion vacancy ordering and metal oxide slab glide but are not well understood and difficult to characterize experimentally. In this thesis, I explain the nature of these lattice differences and phase transformations for O and P-type single-transition-metal layered systems with regards to the active ion and transition metal at hand. This thesis first investigates the nature of vacancy ordering within the O3 host lattice framework, which is currently the most widely synthesized framework for sodium ion intercalating oxides. I generate predicted electrochemical voltage curves for each of the Na-ion intercalating layered TM oxides using a high-throughput framework of density functional theory (DFT) calculations and determine a set of vacancy ordered phases appearing as ground states in all NaxMO₂ systems, and investigate the energy effect of stacking of adjacent layers. I also examine the influence of transition metal mixing and transition metal migration on the materials' thermodynamic properties. Recent work has established the P2 framework as a better electrode candidate structure type than O3, because its slightly larger interlayer spacing allows for faster sodium ion diffusion due to lower diffusion barriers. However, little has been resolved in explaining what stabilizing mechanisms allow for the formation of P-type materials and their synthesis. This work therefore also investigates what stabilizes P2, P3 and O3 materials and what makes them synthesizable at given synthesis conditions, both for the optimization of synthesis techniques and for better-guided material design. It is of further interest to understand why some transition metal oxide systems readily form P2 or P3 compounds while others do not. I investigate several possible stabilizing mechanisms that allow P-type layered sodium metal oxides to by synthesized, and relate these to the choice of transition metal in the metal oxide structure. Finally, this work examines the difficulty of sodium ion intercalation into graphite, which is a commonly used anode material for lithium ion batteries, proposing possible reasons for why graphite does not reversibly intercalate sodium ions and why cointercalation with other compounds is unlikely. This thesis concludes that complex stabilizing mechanisms that go beyond simple electrostatics govern the intercalation of sodium ions into layered systems, giving it advantages and disadvantages over lithium ion batteries and outlining design principles to improve full-cell sodium ion battery materials.
by Alexandra Jeanne Toumar.
Ph. D.

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Li, Xianji. « Metal nitrides as negative electrode materials for sodium-ion batteries ». Thesis, University of Southampton, 2015. https://eprints.soton.ac.uk/374787/.

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Wang, Qing. « High Energy Density Layered Oxide Cathodes for Sodium Ion Batteries ». Electronic Thesis or Diss., Sorbonne université, 2021. https://theses.hal.science/tel-03728228.

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La demande croissante de stockage d'énergie a stimulé des recherches extensives pour la chimie de batteries moins chers et plus durables, tels que le Na-ion. L'un des défis majeurs pour l'application pratique des batteries Na-ion est les performances insuffisantes de cathode, notamment en termes de densité d'énergie. Les oxydes lamellaires de sodium du type O3 sont prometteurs en termes de densité d'énergie, mais ils souffrent d'une cyclabilité insuffisante et d'une mauvaise stabilité à l'humidité. Dans ce contexte, cette thèse se concentre sur la synthèse et la caractérisation de cathodes avancées de type O3 fabriquées à partir de éléments à bas coût qui pourraient dépasser ces limites. Le système Na(Cu,Fe,Mn)O2 comprenant des centres redox à haute tension tels que Fe et Cu est systématiquement étudié, présentant une cyclabilité insatisfaisante qui se révèle provenir de processus d’oxydoréduction inhabituels et de processus structurels à des tensions élevées. Ensuite, la co-substitution de Cu et Ti dans le système NaNi0,5Mn0,5O2 est étudiée, montrant une cyclabilité et une stabilité à l'humidité améliorées. Les compositions optimales identifiées sont compétitives pour l'application, comme le démontre un prototype au format « 18650 ». Enfin, la possibilité d'utiliser l'oxygène comme centre redox pour une capacité élevée est examinée par l'exemple d'une phase O3-NaLi1/3Mn2/3O2 nouvellement obtenue, qui est également utilisée comme composé « modèle » pour approfondir notre connaissance du mécanisme fondamental du redox anionique
The increasing demand for energy storage has stimulated extensive research for cheaper and more sustainable battery chemistries, such as Na-ion. One of the major challenges of the practical application of Na-ion batteries is the insufficient performances of cathode materials, especially in terms of energy density. O3-type sodium layered oxides are promising in terms of energy density, but they suffer from insufficient cyclability and poor moisture stability. In this context, this thesis focuses on the synthesis and characterization of advanced O3-type cathodes made from cheap constitutions which could overcome these limits. First, the Na(Cu,Fe,Mn)O2 system comprising high-voltage redox centers such as Fe and Cu is systematically studied, exhibiting unsatisfactory cyclability which is revealed to originate from structural and unusual redox processes at high voltages. Next, the Cu and Ti co-substitution in NaNi0.5Mn0.5O2 system is investigated, showing improved cyclability and moisture stability. The optimal compositions are competitive for utility as demonstrated by a 18 650 prototype. Lastly, the possibility of using oxygen as redox center for high capacity is also examined by the example of a first achieved O3-NaLi1/3Mn2/3O2 phase, which is also used as a model compound to deepen our understanding of the fundamental anionic redox mechanism

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Dall'Agnese, Yohan. « Study of early transition metal carbides for energy storage applications ». Thesis, Toulouse 3, 2016. http://www.theses.fr/2016TOU30025/document.

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La demande urgente d'innovations dans le domaine du stockage de l'énergie est liée au développement récent de la production d'énergie renouvelable ainsi qu'à la diversification des produits électroniques portables qui consomment de plus en plus d'énergie. Il existe plusieurs technologies pour le stockage et la conversion électrochimique de l'énergie, les plus notables étant les batteries aux ions lithium, les piles à combustible et les supercondensateurs. Ces systèmes sont utilisés de façon complémentaire des uns aux autres dans des applications différentes. Par exemple, les batteries sont plus facilement transportables que les piles à combustible et ont de bonne densité d'énergie alors que les supercondensateurs ont des densités de puissance plus élevés et une meilleure durée de vie. L'objectif principal de ces travaux est d'étudier les performances électrochimiques d'une nouvelle famille de matériaux bidimensionnel appelée MXène, en vue de proposer de nouvelles solutions pour le stockage de l'énergie. Pour y arriver, plusieurs directions ont été explorées. Dans un premier temps, la thèse se concentre sur les supercondensateurs dans des électrolytes aqueux et aux effets des groupes de surface. La seconde partie se concentre sur les systèmes de batterie et de capacités à ions sodium. Une cellule complète comportant une anode en carbone et une cathode de MXène a été développées. La dernière partie de la thèse présente l'étude des MXènes pour les supercondensateur en milieu organique. Une attention particulière est apportée à l'étude du mécanisme d'intercalation des ions entre les feuillets de MXène. Différentes techniques de caractérisations ont été utilisées, en particulier la voltampérométrie cyclique, le cyclage galvanostatique, la spectroscopie d'impédance, la microscopie électronique et la diffraction des rayons X
An increase in energy and power densities is needed to match the growing energy storage demands linked with the development of renewable energy production and portable electronics. Several energy storage technologies exist including lithium ion batteries, sodium ion batteries, fuel cells and electrochemical capacitors. These systems are complementary to each other. For example, electrochemical capacitors (ECs) can deliver high power densities whereas batteries are used for high energy densities applications. The first objective of this work is to investigate the electrochemical performances of a new family of 2-D material called MXene and propose new solutions to tackle the energy storage concern. To achieve this goal, several directions have been explored. The first part of the research focuses on MXene behavior as electrode material for electrochemical capacitors in aqueous electrolytes. The next part starts with sodium-ion batteries, and a new hybrid system of sodium ion capacitor is proposed. The last part is the study of MXene electrodes for supercapacitors is organic electrolytes. The energy storage mechanisms are thoroughly investigated. Different characterization techniques were used in this work, such as cyclic voltammetry, galvanostatic charge-discharge, electrochemical impedance spectroscopy, scanning electron microscopy and X-ray diffraction

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Murphy, Denissa Tjiadarma. « Structural Investigation of Electrodes for Rechargeable Alkali Ion Batteries ». Thesis, The University of Sydney, 2017. http://hdl.handle.net/2123/17699.

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This thesis describes the in-depth characterisation of the structure, including detailed cation distributions, of positive electrode materials for lithium and sodium ion batteries. As the crystal chemistry influences the mobility of lithium and sodium ions, the structure and electrochemical property relationships for select compounds have been established. The majority of this thesis is focused on the structural characterisation of LiMn2-xTixO4 (0.2 ≤ x ≤ 1.5). A combination of X-ray and neutron powder diffraction studies along with spectroscopic techniques and physical property measurements were employed to elucidate the complex metal ion ordering of the spinel electrodes. It was found that the synthesis conditions, particularly cooling regimes, play an important part in the final structures of LiMn1.8Ti0.2O4 and LiMnTiO4. The bulk substitution of 10% and 50% manganese with titanium heavily influenced the cation distribution and consequently, the electrochemistry of these compounds. In situ diffraction studies revealed the contrasting structural evolutions of LiMn1.8Ti0.2O4 and LiMnTiO4 during charge and discharge cycles. The potential of sodium silicate materials as positive electrodes for sodium ion batteries was explored. The fundamental crystal chemistry of Na2MnSiO4 and Na2CoSiO4 was established prior to electrochemical cycling. The as prepared Na2CoSiO4 exhibited better conductivity than the manganese analogue. Improvement of the conductivity of Na2MnSiO4 was achieved through carbon coating of the material. Finally, the addition of Li2RuO3 to form the lithium rich 0.5Li2RuO3∙0.5LiMO2 (M = Co and Ni) electrodes has resulted in the increased the stability of the layered structures of the compounds. The electrochemically active Li2RuO3 contributed to the excellent specific capacity and rate capability of the cobalt compound. Overall superior electrochemical performance was achieved by the nickel analogue.

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Wood, Stephen. « Computer modelling studies of new electrode materials for rechargeable batteries ». Thesis, University of Bath, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.687357.

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Developing a sustainable energy infrastructure for the 21st century requires the large scale development of renewable energy resources. Fully exploiting these inherently intermittent supplies will require advanced energy storage technologies, with rechargeable Li-ion and Na-ion batteries considered highly promising for both vehicle electrification and grid storage applications. However, the performance required of battery materials has not been achieved, and significant improvements are needed. Modern computational techniques allow the elucidation of structure-property relationships at the atomic level and are valuable tools in providing fundamental insights into novel materials. Therefore, in this thesis a combination of atomistic simulation and ab initio density functional theory (DFT) techniques have been used to study a number of potential battery cathode materials. Firstly, Na2FePO4F and NaFePO4 are interesting materials that have been reported recently as attractive positive electrodes for Na-ion batteries. Here, we report their Na-ion conduction behaviour and intrinsic defect properties using atomistic simulation methods. Na+ ion conduction in Na2FePO4F is predicted to be two-dimensional (2D) in the interlayer plane. Na ion migration in NaFePO4 is restricted to the [010] direction along a curved trajectory, leading to quasi-1D Na+ diffusion. Furthermore, Na/Fe antisite defects are predicted to have a lower formation energy in NaFePO4 than Na2FePO4F. The higher probability of tunnel occupation with a relatively immobile Fe2+ cation - along with a greater volume change on redox cycling - contributes to the poor electrochemical performance of NaFePO4. Secondly, work on the Na2FePO4F system is extended to include investigation of the surface structures and energetics. The equilibrium morphology is found to be essentially octagonal, compressed slightly along the [010] direction, and is dominated by the (010), (021), (122) and (110) surfaces. The calculated growth morphology is a more ``rod-like'' nanoparticle, with the (021), (023), (110) and (112) planes predominant. The (010) surface lies parallel to the Na layers in the ac plane and is unlikely to facilitate Na+ intercalation. As such, its prominence in the equilibrium morphology, and absence from the growth morphology, suggests nanoparticles synthesised in a kinetically limited regime should provide higher rate performance than those synthesised in close to equilibrium conditions. Surface redox potentials for Na2FePO4F derived using DFT vary between 2.76 - 3.37 V, in comparison to a calculated bulk cell voltage of 2.91 V. Most significantly, the lowest energy potentials are found for the (130) and (001) planes suggesting that upon charging Na+ will first be extracted from these surfaces, and inserted lastly upon discharging. Thirdly, the mixed phosphates Na4M3(PO4)2P2O7 (M=Fe, Mn, Co, Ni) are explored as a fascinating new class of materials reported to be attractive Na-ion cathodes, displaying low volume changes upon cycling indicative of long lifetime operation. Key issues surrounding intrinsic defects, Na-ion migration mechanisms and voltage trends have been investigated through a combination of atomistic energy minimisation, molecular dynamics and DFT simulations. The MD results suggest Na+ diffusion extends across a 3D network of migration pathways with an activation barrier of 0.20-0.24 eV, and diffusion coefficients (DNa) of 10-10-10-11 cm2s-1 at 325 K, suggesting high rate capability. The cell voltage trends, explored using DFT methods, indicate that doping the Fe-based cathode with Ni can significantly increase the voltage, and hence energy density. Finally, DFT simulations of K+-stabilised α-MnO2 have been combined with aberration corrected-STEM techniques to study the surface energetics, particle morphologies and growth mechanism. α-K0.25MnO2 grown through a hydrothermal synthesis method is found to produce primary nanowires with preferential growth along the [001] direction. Primary nanowires attach through a shared (110) interface to form larger secondary nanowires. This is in agreement with DFT simulations with the {100}, {110} and {211} surfaces displaying the lowest surface energies. The ranking of surface energies is driven by Mn coordination environments and surface relaxation. The calculated equilibrium morphology of α-K0.25MnO2 is consistent with the observed primary nanowires from high resolution electron microscopy images.

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David, Lamuel Abraham. « Van der Waals sheets for rechargeable metal-ion batteries ». Diss., Kansas State University, 2015. http://hdl.handle.net/2097/32796.

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Doctor of Philosophy
Department of Mechanical and Nuclear Engineering
Gurpreet Singh
The inevitable depletion of fossil fuels and related environmental issues has led to exploration of alternative energy sources and storage technologies. Among various energy storage technologies, rechargeable metal-ion batteries (MIB) are at the forefront. One dominant factor affecting the performance of MIB is the choice of electrode material. This thesis reports synthesis of paper like electrodes composed for three representative layered materials (van der Waals sheets) namely reduced graphene oxide (rGO), molybdenum disulfide (MoS₂) and hexagonal boron nitride (BN) and their use as a flexible negative electrode for Li and Na-ion batteries. Additionally, layered or sandwiched structures of vdW sheets with precursor-derived ceramics (PDCs) were explored as high C-rate electrode materials. Electrochemical performance of rGO paper electrodes depended upon its reduction temperature, with maximum Li charge capacity of 325 mAh.g⁻¹ observed for specimen annealed at 900°C. However, a sharp decline in Na charge capacity was noted for rGO annealed above 500 °C. More importantly, annealing of GO in NH₃ at 500 °C showed negligible cyclability for Na-ions while there was improvement in electrode's Li-ion cycling performance. This is due to increased level of ordering in graphene sheets and decreased interlayer spacing with increasing annealing temperatures in Ar or reduction at moderate temperatures in NH₃. Further enhancement in rGO electrodes was achieved by interfacing exfoliated MoS₂ with rGO in 8:2 wt. ratios. Such papers showed good Na cycling ability with charge capacity of approx. 225.mAh.g⁻¹ and coulombic efficiency reaching 99%. Composite paper electrode of rGO and silicon oxycarbide SiOC (a type of PDC) was tested as high power-high energy anode material. Owing to this unique structure, the SiOC/rGO composite electrode exhibited stable Li-ion charge capacity of 543.mAh.g⁻¹ at 2400 mA.g⁻¹ with nearly 100% average cycling efficiency. Further, mechanical characterization of composite papers revealed difference in fracture mechanism between rGO and 60SiOC composite freestanding paper. This work demonstrates the first high power density silicon based PDC/rGO composite with high cyclic stability. Composite paper electrodes of exfoliated MoS₂ sheets and silicon carbonitride (another type of PDC material) were prepared by chemical interfacing of MoS₂ with polysilazane followed by pyrolysis . Microscopic and spectroscopic techniques confirmed ceramization of polymer to ceramic phase on surfaces on MoS₂. The electrode showed classical three-phase behavior characteristics of a conversion reaction. Excellent C-rate performance and Li capacity of 530 mAh.g⁻¹ which is approximately 3 times higher than bulk MoS₂ was observed. Composite papers of BN sheets with SiCN (SiCN/BN) showed improved electrical conductivity, high-temperature oxidation resistance (at 1000 °C), and high electrochemical activity (~517 mAh g⁻¹ at 100 mA g⁻¹) toward Li-ions generally not observed in SiCN or B-doped SiCN. Chemical characterization of the composite suggests increased free-carbon content in the SiCN phase, which may have exceeded the percolation limit, leading to the improved conductivity and Li-reversible capacity. The novel approach to synthesis of van der Waals sheets and its PDC composites along with battery cyclic performance testing offers a starting point to further explore the cyclic performance of other van der Waals sheets functionalized with various other PDC chemistries.

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Han, Ruixin. « SYNTHESIS, AND STRUCTURAL, ELECTROCHEMICAL, AND MAGNETIC PROPERTY CHARACTERIZATION OF PROMISING ELECTRODE MATERIALS FOR LITHIUM-ION BATTERIES AND SODIUM-ION BATTERIES ». UKnowledge, 2018. https://uknowledge.uky.edu/chemistry_etds/90.

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Iron oxides, have been widely studied as promising anode materials in lithium-ion batteries (LIBs) for their high capacity (≈ 1000 mA h g-1 for Fe2O3 and Fe3O4,), non-toxicity, and low cost. In this work, β-FeOOH has been evaluated within a LIB half-cell showing an excellent capacity of ≈ 1500 mA h g-1 , superior to Fe2O3 or Fe3O4. Reaction mechanism has been proposed with the assistance of X-ray photoelectron spectroscopy (XPS). Various magnetic properties have been suggested for β-FeOOH such as superparamagnetism, antiferromagnetism and complex magnetism, for which, size of the material is believed to play a critical role. Here, we present a size-controlled synthesis of β-FeOOH nanorods. Co-existing superparamagnetism and antiferromagnetism have been revealed in β-FeOOH by using a Physical Property Measurement System (PPMS). Compared with the high price of lithium in LIBs, sodium-ion batteries (SIBs) have attracted increasing attentions for lower cost. Recent studies have reported Na0.44MnO2 to be a promising candidate for cathode material of SIBs. This thesis has approached a novel solid-state synthesis of Na0.44MnO2 whiskers and a nano-scaled open cell for in situ TEM study. Preliminary results show the first-stage fabrication of the cell on a biasing protochip.

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Zhang, Huang [Verfasser], et S. [Akademischer Betreuer] Passerini. « Polyanionic cathode materials for sodium-ion batteries / Huang Zhang ; Betreuer : S. Passerini ». Karlsruhe : KIT-Bibliothek, 2019. http://d-nb.info/1178528162/34.

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Richards, William D. (William Davidson). « Ab initio investigations of solid electrolytes for lithium- and Sodium-ion batteries ». Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/108967.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Materials Science and Engineering, 2017.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 119-127).
Solid-state electrolytes have the potential to dramatically improve the safety and longevity of state-of-the-art battery technology by replacing the flammable organic electrolytes currently employed in Li-ion batteries. Recent advances in the development of new thiophosphate electrolytes have reenergized the field by achieving room temperature conductivities exceeding those liquid electrolytes, but a number of practical challenges to their widespread adoption still exist. This thesis applies ab initio computational methods based on density functional theory to investigate the structural origins of high conductivity in ionic conductor materials and provides a thermodynamic explanation of why the integration of these newly developed thiophosphates into high-rate cells has proven difficult in practice, often resulting in high interfacial resistance. As a result of these computational investigations, we report the prediction and synthesis of a new high performance sodium-ion conducting material: NaioSnP 2S 12, with room temperature ionic conductivity of 0.4 mS cm-1, which rivals the conductivity of the best sodium sulfide solid electrolytes to date. We computationally investigate the variants of this compound where Sn is substituted by Ge or Si and find that the latter may achieve even higher conductivity. We then investigate the relationship between anion packing and ionic transport in fast Li-ion conductors, finding that a bcc-like anion framework is desirable for achieving high ionic conductivity, and that this anion arrangement is present in a disproportionately high number of known Li-conducting materials, including Na10SnP2S12 and its structural analog Li10GeP2S2 . Using this bcc anion lattice as a screening criterion, we show that the I4 material LiZnPS4 also contains such a framework and has the potential for very high ionic conductivity. While the stoichiometric material has poor ionic conductivity, engineering of its composition to introduce interstitial lithium defects is able to exploit the low migration barrier of the bcc anion structure. Thermodynamic calculations predict a solid-solution regime in this system that extends to x = 0.5 in Li1+2xZn-xPS 4 , thus it may yield a new ionic conductor with exceptionally high lithium-ion conductivity, potentially exceeding 50 mS cm- 1 at room temperature. Finally, we develop a computational methodology to examine the thermodynamics of formation of resistive interfacial phases through mixing of the electrode and electrolyte. The results of the thermodynamic model of interfacial phase formation are well correlated with experimental observations and battery performance, and predict that thiophosphate electrolytes have especially high reactivity with high voltage oxide cathodes and a narrow electrochemical stability window. We also find that a number of known electrolytes are not inherently stable, but react in situ with the electrode to form passivating but ionically conducting barrier layers.
by William D. Richards.
Ph. D.

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LI, TAO. « The Study of Various Anode Materials for Sodium (or Lithium)-Ion Batteries ». Doctoral thesis, Università degli studi di Genova, 2019. http://hdl.handle.net/11567/939856.

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room-temperature sodium-ion batteries (NIBs or SIBs) have raised a great deal of attention for grid-level applications considering the sustainability advantages of NIBs. Significant progress has been made for NIB cathodes by adapting the knowledge learned on lithium-ion batteries (LIBs). Simultaneously, numerous attempts have been made to find suitable anodes for NIBs, however, the research to improve NIB technologies rema ns a challenge. This thesis presents fundamental studies of various anode materials for NIBs from different aspects. Surface and interface engineering of nanostructured anatase TiO2 anode through Al2O3 surface modification and wise electrolyte selection is conducted. The results show that Al2O3 coating provides beneficial effects to the TiO2-based anodes and the modified TiO2 exhibits significant improvements in cycling performance using electrolyte with binary ethylene carbonate (EC) and propylene carbonate (PC) solvent mixture without the need of the commonly used fluoroethylene carbonate (FEC) additive. The achieved excellent electrochemical performance (a high reversible capacity of 188.1 mAh g−1 at 0.1C after 50 cycles, good rate capability up to 5C, and long-term cycling performance for 650 cycles at a high rate of 1C) can be ascribed to the synergistic effects of surface and interface engineering enabling the formation of a stable and highly ionic conductive interface layer in EC:PC based electrolyte which combines the native SEI film and an ‘artificial’ SEI layer of irreversibly formed Na−Al−O. A dual-modification approach of Mo doping combined with AlF3 coating is also introduced to enhance the sodium storage activity of anatase TiO2. The Mo-doped anatase TiO2 synthesized by a simple co-precipitation method delivers an enhanced reversible capacity compare to pristine TiO2 (139.8 vs. 100.7 mAh g−1 at 0.1C after 50 cycles) due to enhanced electronic/ionic conductivity. Via further coating AlF3 using a modified solid-state method, a much higher reversible capacity of 178.9 mAh g−1 with good cycle stability and excellent rate capabilities up to 10C can be finally obtained. The experimental results indicate that AlF3 surface coating could effectively reduce solid electrolyte interfacial resistance, enhance electrochemical reactivity at the surface/interface region, and lower polarization during cycling. As for alloy-type anode of Sn with high theoretical capacity of 847 mAh g−1 but experiences a high volume expansion of 420% upon sodiation, we carry out a fundamental study of the degradation mechanisms that occur in Sn during sodiation-desodiation by employing a Sn thick film as the anode. Electron microscopy reveals new deformation mechanisms, as multiple Sn whiskers nucleate on the surface of the Sn, while pores form within the Sn (over the Na-ion penetration distance) after electrochemical cycling. These mechanisms are in addition to the dry lake-bed fracture that is also observed. Such whiskers and pores may be more-subtle at the nanoscale, and therefore have not been reported for sub-micron Sn particles in porous electrodes. The simplified planar geometry of the Sn sheet allows to dispense with the influence of the binder and carbon additives that are required in porous electrodes and the implementation of the Randles-Sevick equation provides a first experimental estimate for the diffusion coefficient of Na+ in Sn as 6.45×10−12 cm2 s−1. Finally, we explore facile synthesis of carbon materials from low cost carbon source of CaC2 using a novel sulfur-based thermo-chemical etching technique. Comprehensive analysis using X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and N2 adsorption−desorption isotherms, reveals a highly graphitized mesoporous structure for the CaC2-derived carbon with a specific surface area of 159.5 m2 g−1. Microscopic analysis displays micron-scale mesoporous frameworks (4–20 μm) with a distinct layered structure along with agglomerates of highly graphitized nanosheets (about 10 nm in thickness and 1–10 μm of lateral size). The application of the as-prepared carbon materials as anode for NIBs and LIBs is also preliminarily studied.

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Lu, Xiaoxiao. « The improvement of electrochemical performance of SnO2-based nanocomposites as anodes for lithium ion and sodium ion batteries ». Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/the-improvement-of-electrochemical-performance-of-sno2based-nanocomposites-as-anodes-for-lithium-ion-and-sodium-ion-batteries(d0d78e2a-2ed4-4274-b3fe-9c018992e15a).html.

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Nowadays, low carbon economy becomes a significant topic over the world. Due to the decreasing amount of fossil energy source and the worsening environmental pollution, traditional energy sources should be transferred to renewable energy sources. A transition to renewable energy will require radical changes to systems and technologies for energy storage. Lithium ion (Li-ion) batteries are now considered as the most important electrochemical energy source for portable devices, electrical vehicles and expected to be used in grid electrical energy storage. Beside on Li-ion batteries, sodium ion (Na-ion) batteries are another promising energy source, which have the advantages in cost, safety and environmental factors, and they could be used for stationary energy storage systems and large vehicles. Tin-based nanocomposites are promising to replace the traditional graphite for Li-ion batteries to achieve a higher battery performance. In 2005, Sony Corporation launched the first Sn-based anode Li-ion batteries (Nexelion) to obtain a 50% increase in volumetric capacity over the conventional battery, which marked Li-ion batteries to enter into a new cutting edge. However, Sn-based materials faced with challenges. The battery performance was limited by a low cycling life and low rate performance, and methods should be devised to overcome these shortcomings. In this thesis, SnO2-based nanocomposites, including the graphene-SnO2, the carbon-coated graphene-SnO2 and the carbon-coated nanostructured SnO2 have been prepared and investigated as anodes for Li-ion and Na-ion batteries. The microstructure, electrochemical performances and even the degradation mechanisms have been investigated as the effects for different composite materials. Chapter 4 reports an amorphous carbon coated graphene-SnO2 composite which exhibited an enhanced cycling stability. In previous researches, the performance enhancements of that type of materials were commonly attributed to the carbon coating enhancing the electronic conductivity. However, it is found that the carbon coating deeply relates to the microstructure stability of the active materials, the performance enhancement can be attributed to the enhancement of structural stability. Chapter 5 reports same composites with various graphene to amorphous carbon mass ratios. In this chapter, we try to find out the optimized composition and understanding the different roles of graphene and amorphous carbon in that type of composites. It is found that an optimised graphene to carbon mass ratio can effectively enhance the structural stability and the electrode conductivity. Chapter 6 reports a carbon-coated flower-like nanostructured SnO2 for Na-ion battery application, which has been demonstrated to have a high reversible capacity and high rate performance. The carbon coating is found to help in the formation of a high quality solid electrolyte interface (SEI) layer on the surface of the active materials. These researches focus on modifying SnO2 and SnO2-based materials by carbon coating technologies, which aim to develop novel electrode materials to obtain a better battery performance for Li-ion and Na-ion batteries.

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Wang, Luyuan Paul. « Matériaux à hautes performance à base d'oxydes métalliques pour applications de stockage de l'énergie ». Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAI031/document.

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Le cœur de technologie d'une batterie réside principalement dans les matériaux actifs des électrodes, qui est fondamental pour pouvoir stocker une grande quantité de charge et garantir une bonne durée de vie. Le dioxyde d'étain (SnO₂) a été étudié en tant que matériau d'anode dans les batteries Li-ion (LIB) et Na-ion (NIB), en raison de sa capacité spécifique élevée et sa bonne tenue en régimes de puissance élevés. Cependant, lors du processus de charge/décharge, ce matériau souffre d'une grande expansion volumique qui entraîne une mauvaise cyclabilité, ce qui empêche la mise en oeuvre de SnO₂ dans des accumulateurs commerciaux. Aussi, pour contourner ces problèmes, des solutions pour surmonter les limites de SnO₂ en tant qu'anode dans LIB / NIB seront présentées dans cette thèse. La partie initiale de la thèse est dédié à la production de SnO₂ et de RGO (oxyde de graphène réduit)/SnO₂ par pyrolyse laser puis à sa mise en oeuvre en tant qu'anode. La deuxième partie s'attarde à étudier l'effet du dopage de l'azote sur les performances et permet de démontrer l'effet positif sur le SnO₂ dans les LIB, mais un effet néfaste sur les NIB. La partie finale de la thèse étudie l'effet de l'ingénierie matricielle à travers la production d'un composé ZnSnO₃. Enfin, les résultats obtenus sont comparés avec l'état de l'art et permettent de mettre en perspectives ces travaux
The heart of battery technology lies primarily in the electrode material, which is fundamental to how much charge can be stored and how long the battery can be cycled. Tin dioxide (SnO₂) has received tremendous attention as an anode material in both Li-ion (LIB) and Na-ion (NIB) batteries, owing to benefits such as high specific capacity and rate capability. However, large volume expansion accompanying charging/discharging process results in poor cycleability that hinders the utilization of SnO₂ in commercial batteries. To this end, engineering solutions to surmount the limitations facing SnO₂ as an anode in LIB/NIB will be presented in this thesis. The initial part of the thesis focuses on producing SnO₂ and rGO (reduced graphene oxide)/SnO₂ through laser pyrolysis and its application as an anode. The following segment studies the effect of nitrogen doping, where it was found to have a positive effect on SnO₂ in LIB, but a detrimental effect in NIB. The final part of the thesis investigates the effect of matrix engineering through the production of a ZnSnO₃ compound. Finally, the obtained results will be compared and to understand the implications that they may possess

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Dacek, Stephen Thomas III. « First principles investigation and design of fluorophosphate sodium-ion battery cathodes ». Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/109684.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Materials Science and Engineering, 2016.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 119-140).
Lithium-ion batteries are currently the most widely used consumer energy storage technology. Recently, lithium-ion batteries have been evaluated for use in mitigating the intermittent power supply of leading renewable energy technologies, thereby enabling their use on the electric grid. In order to facilitate the widespread adoption of electric vehicles and renewable energy technologies, the energy-densities, lifetimes, and cost of batteries must be improved. Due to concerns over long-term lithium availability, sodium-ion batteries are currently being investigated as an alternative to lithium-ion batteries in grid-level applications. In this thesis, we use ab inritio methods to characterize th high-voltage sodium-ion fluorophosphate with formula NaxV2(PO4)2O2yF3-2y as an alternative chemistry to Li-ion batteries. In Chapter 3 we investigate the sodium-extraction limitations in the NaxV2(PO4)2O2yF3-2 fluorophosphate. Specifically, we focus on the potential to reversibly extract sodium beyond the 1 by Stephen Thomas Dacek, III
Ph. D.

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Dou, Xinwei [Verfasser], et S. [Akademischer Betreuer] Passerini. « Hard Carbon Anode Materials for Sodium-ion Batteries / Xinwei Dou ; Betreuer : S. Passerini ». Karlsruhe : KIT-Bibliothek, 2019. http://d-nb.info/1179963695/34.

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Posch, P., P. Bottke, M. Wilkening et I. Hanzu. « Hydrothermally Synthesized Nanostructured Sodium Titanates as Negative Electrode Materials for Na-Ion Batteries ». Diffusion fundamentals 21 (2014) 22, S.1, 2014. https://ul.qucosa.de/id/qucosa%3A32432.

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CHEN, LIN. « Investigation of inorganic nanocrystals as electrode material for lithium and sodium ion batteries ». Doctoral thesis, Università degli studi di Genova, 2018. http://hdl.handle.net/11567/929837.

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The worldwide demand for a clean, safe, high specific capacity and high energy rechargeable batteries systems keeps increasing. Li-ion batteries (LIBs) and Na-ion batteries (NIBs) have been proved to be reliable technologies, for a large variety of applications, ranging from portable high-end electronics, stationary.

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Saavedra, Rios Carolina del Mar. « Etude des carbones durs issus de la biomasse pour l’application dans les batteries Sodium-ion ». Thesis, Université Grenoble Alpes, 2020. https://thares.univ-grenoble-alpes.fr/2020GRALI072.pdf.

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La demande croissante en batteries Lithium-ion a suscité une certaine inquiétude concernant l'approvisionnement en matières premières critiques nécessaires à leur production, en particulier les ressources en Li, Co, Ni et Cu. La technologie Sodium-ion apparait comme une alternative pouvant utiliser des ressources abondantes et uniformément réparties, et qui pourrait réduire le coût des batteries par rapport au Lithium-ion. Toutefois, le débouché commercial des batteries Sodium-ion est encore limité par le développement de matériaux d'électrode négative à haute performance et bas coût. L'option la plus prometteuse est un matériau carboné désordonné appelé carbone dur, obtenu par traitement thermique à haute température de précurseurs organiques. Malgré ses bonnes performances, le carbone dur est toujours plus cher que le graphite utilisé dans les batteries Lithium-ion, étant donné le coût élevé de ses précurseurs synthétiques. La biomasse lignocellulosique a récemment attiré l'attention en tant que précurseur du carbone dur, étant donné sa nature renouvelable, son accessibilité et son faible coût. Cependant, la grande variabilité des matières premières de la biomasse ainsi que le faible rendement de la réaction de pyrolyse, rendent leur application commerciale plutôt difficile. De plus, le rôle de la composition de la biomasse sur les propriétés du carbone dur n’est pas complètement compris. Le travail de recherche présenté ici est une approche interdisciplinaire, visant à élucider l'impact de la composition de la biomasse sur les propriétés physico-chimiques et électrochimiques des carbones durs résultants ainsi que le rendement de leur synthèse. Un ensemble de 25 précurseurs ont été sélectionnés pour cette étude. La composition de chaque précurseur, telles que le contenu organique et inorganique élémentaire, et le contenu macromoléculaire, ont été évaluées. Les carbones durs synthétisés ont été caractérisés par des techniques de XRD, Raman, SEM, TEM, SAXS, XPS et de cyclage galvanostatique. Le contenu et la composition inorganique du précurseur, en particulier la présence de composés de Si, Ca et K, ont semblé jouer un rôle essentiel dans le développement de la structure et de la surface du carbone dur. Par conséquent, ils ont un impact négatif important sur les performances du carbone dur, en produisant des irréversibilités élevées. Compte tenu de leur faible teneur en cendres couplé à leur faible cout et leur faible impact environnemental, les résidus forestiers et certain résidus agricoles, semblent être le meilleur compromis pour l'application du carbone dur
The ever-increasing demand for Lithium-ion batteries has raised some concern regarding the supply of the critical raw materials needed for their production, especially the Li, Co, Ni and Cu resources. The Sodium-ion technology appears to be an alternative which potentially uses abundant, and evenly distributed resources, that is able to reduce the cost of the batteries compared to Lithium-ion. However, the commercial intrusion of Sodium-ion batteries is still limited by the development of low-cost and high-performance negative electrode material. The most promising option is a disordered carbonaceous material called hard carbon obtained from high-temperature thermal treatment of organic precursors. Despite its good performance, hard carbon is still more expensive than the graphite used in Lithium-ion batteries, given the high cost of the synthetic precursors. Lignocellulosic biomass has recently attracted attention as a hard carbon precursor, given its renewable nature, accessibility, and low cost. However, the high variability of biomass feedstock, together with the poor yield of the pyrolysis reaction, make their commercial application rather difficult. Moreover, there is no clear understanding of the biomass composition role on the hard carbon properties. The research work presented here is an interdisciplinary approach, aiming to elucidate the biomass composition's impact on the physicochemical and electrochemical properties of the derived hard carbons as well as their synthesis yield. A set of 25 lignocellulosic biomass precursors have been selected for this study. The composition of each biomass precursor, such as the elemental organic and inorganic content, and the macromolecular contents were evaluated in detail. The synthesised hard carbons were characterised by XRD, Raman, SEM, TEM, SAXS, XPS, and galvanostatic cycling techniques. The inorganic content and composition of the precursor, particularly the presence of Si, Ca, and K compounds, was observed to play a critical role in developing the hard carbon structure and surface. Therefore, they have a strong negative impact on hard carbon performances, producing high irreversibility. Because of their low ash-content, coupled with their low cost and environmental impact, precursors such as forestry residues, and some agricultural residues, appeared to be the best compromise for hard carbon application

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Brown, James Emery. « Advances in electrical energy storage using core-shell structures and relaxor-ferroelectric materials ». Diss., Kansas State University, 2018. http://hdl.handle.net/2097/38779.

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Doctor of Philosophy
Department of Chemistry
Jun Li
Electrical energy storage (EES) is crucial in todays’ society owing to the advances in electric cars, microelectronics, portable electronics and grid storage backup for renewable energy utilization. Lithium ion batteries (LIBs) have dominated the EES market owing to their wide use in portable electronics. Despite the success, low specific capacity and low power rates still need to be addressed to meet the increasing demands. Particularly, the low specific capacity of cathode materials is currently limiting the energy storage capability of LIBs. Vanadium pentoxide (V₂O₅) has been an emerging cathode material owing to its low cost, high electrode potential in lithium-extracted state (up to 4.0 V), and high specific capacities of 294 mAh g⁻¹ (for a 2 Li⁺/V₂O₅ insertion process) and 441 mAh g⁻¹ (for a 3 Li⁺/V₂O₅ insertion process). However, the low electrical conductivities and slow Li⁺ ion diffusion still limit the power rate of V₂O₅. To enhance the power-rate capability we construct two core-shell structures that can achieve stable 2 and 3 Li⁺ insertion at high rates. In the first approach, uniform coaxial V₂O₅ shells are coated onto electrospun carbon nanofiber (CNF) cores via pulsed electrodeposition. The materials analyses confirm that the V₂O₅ shell after 4 hours of thermal annealing at 300 °C is a partially hydrated amorphous structure. SEM and TEM images indicate that the uniform 30 to 50 nm thick V₂O₅ shell forms an intimate interface with the CNF core. Lithium insertion capacities up to 291 and 429 mAh g⁻¹ are achieved in the voltage ranges of 4.0 – 2.0 V and 4.0 – 1.5 V, respectively, which are in good agreement with the theoretical values for 2 and 3 Li⁺/V₂O₅ insertion. Moreover, after 100 cycles, remarkable retention rates of 97% and 70% are obtained for 2 and 3 Li⁺/V₂O₅ insertion, respectively. In the second approach, we implement a three-dimensional (3D) core-shell structure consisting of coaxial V₂O₅ shells sputter-coated on vertically aligned carbon nanofiber (VACNF) cores. The hydrated amorphous microporous structure in the “as-deposited” V₂O₅ shells and the particulated nano-crystalline V₂O₅ structure formed by thermal annealing are compared. The former provides remarkably high capacity of 360 and 547 mAh g⁻¹ in the voltage range of 4.0 – 2.0 V and 4.0 – 1.5 V, respectively, far exceeding the theoretical values for 2 and 3 Li⁺/V₂O₅ insertion, respectively. After 100 cycles of 3 Li⁺/V₂O₅ insertion/extraction at 0.20 A g⁻¹ (~ C/3), ~ 84% of the initial capacity is retained. After thermal annealing, the core-shell structure presents a capacity of 294 and 390 mAh g⁻¹, matching well with the theoretical values for 2 and 3 Li⁺/V₂O₅ insertion. The annealed sample shows further improved stability, with remarkable capacity retention of ~100% and ~88% for 2 and 3 Li⁺/V₂O₅ insertion/extraction. However, due to the high cost of Li. alternative approaches are currently being pursued for large scale production. Sodium ion batteries (SIB) have been at the forefront of this endeavor. Here we investigate the sodium insertion in the hydrate amorphous V₂O₅ using the VACNF core-shell structure. Electrochemical characterization was carried out in the potential ranges of 3.5 – 1.0, 4.0 – 1.5, and 4.0 – 1.0 (vs Na/Na⁺). An insertion capacity of 196 mAh g-1 is achieved in the potential range of 3.5 – 1.0 V (vs Na/Na⁺) at a rate of 250 mA g⁻¹. When the potential window is shifted upwards to 4.0 – 1.5 V (vs Na/Na⁺) an insertion capacity of 145 mAh g⁻¹ is achieved. Moreover, a coulombic efficiency of ~98% is attained at a rate of 1500 mA g⁻¹. To enhance the energy density of the VACNF-V₂O₅ core-shell structures, the potential window is expanded to 4.0 – 1.0 V (vs Na/Na⁺) which achieved an initial insertion capacity of 277 mAh g⁻¹. The results demonstrate that amorphous V₂O₅ could serve as a cathode material in future SIBs.

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Liang, Wenfeng. « Metal Organic Composites Derived Tin Dioxide/C Nanoparticles For Sodium-Ion Battery ». University of Akron / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=akron1460304081.

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Castro, Alexandre. « Développement de batteries tout solide sodium ion à base d’électrolyte en verre de chalcogénures ». Thesis, Rennes 1, 2018. http://www.theses.fr/2018REN1S126/document.

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L'évolution des consommations énergétiques au cours des dernières décennies entraîne des modifications majeures dans la conception des systèmes électriques autonomes à fournir, que ce soit pour des applications électriques ou électroniques. La nécessité présente de réaliser des générateurs capables de délivrer l'énergie suffisante, avec une garantie de sûreté maximale, impose à la recherche l'exploration de nouvelles voies de stockage. Les voies actuelles par accumulateurs au lithium tendent à montrer leurs limites, tant stratégiques qu'environnementales. Dans ce cadre, la construction de nouveaux systèmes électrochimiques mettant en œuvre le sodium ouvre une possibilité de réalisation d'accumulateurs sans lithium. Le besoin de batteries toujours plus performantes oblige à des conceptions innovantes, abandonnant la voie liquide au profit de systèmes tout solide plus sécuritaires. De plus, la miniaturisation de l'électronique conduit à revoir le dimensionnement des batteries, vers des batteries de type micro, pour lesquelles l'intérêt d'un empilement tout solide n'est plus à démontrer. Aujourd'hui, des verres de chalcogénures au soufre permettent l'accès à des conductivités ioniques qui laissent entrevoir la possibilité d'une réalisation de batteries tout solide, à la fois sous forme de micro batteries ou de batteries massives. Un effort de recherche a été porté à la formulation de ces verres de chalcogénures afin d'obtenir des conductivités ioniques maximales et des propriétés autorisant leur utilisation comme électrolyte. La modification de ces verres met alors en lumière l'intérêt des différents éléments les composant. L'étude de la mise en forme de l'électrolyte par dépôts de type couches minces (obtenues par Radio Fréquence Magnétron Sputering, RFMS) prouve la faisabilité de ces micro batteries tout solide au sodium. Par la suite, la réalisation de batteries massives tout solide a demandé la synthèse de deux matériaux de cathode (NaCrO2 et Na[Ni0,25Fe0,5Mn0,25]O2) et de deux matériaux d'anode (Na15Sn4 et Na) permettant ainsi la mise en œuvre de quatre empilements électrochimiques, tous caractérisés comme accumulateurs. Enfin, l'amélioration des interfaces grâce à un gel-polymère a permis de perfectionner les propriétés des assemblages avec notamment une augmentation des vitesses de charge/décharge et une mobilisation accrue des matériaux actifs de cathode
The evolution of energy consumption in recent decades has led to major changes in the design of autonomous electrical systems dedicated to either electrical or electronic applications. The present demand to build generators capable of delivering sufficient energy, with a guarantee of maximum safety, requires to explore new storage routes. The current lithium battery routes tend to show their limits, both strategic and environmental. In this context, the construction of new electrochemical systems implementing sodium opens the way of the lithium-free accumulators production. The need for ever more efficient batteries requires innovative designs, giving up the liquid path in favor of stronger solid systems. In addition, the miniaturization of electronics leads to a review of the size of the batteries, to micro-type batteries, for which the interest of a solid stack is no longer to demonstrate. Today, sulfur chalcogenide glasses allow access to ionic conductivities that suggest the possibility of a realization of all solid batteries, both in the form of micro batteries or massive batteries. A research effort has been made to formulate these chalcogenide glasses in order to obtain a maximum of ionic conductivity and properties allowing their use as electrolytes. The composition of these glasses highlights the interest of the different elements for such properties. The study of the electrolyte shaping by thin-film deposition (obtained by Radio Frequency Magnetron Sputering, RFMS) proves the feasibility of these all-solid sodium micro-batteries. Subsequently, the realization of massive all solid batteries required the synthesis of two cathode materials (NaCrO2 and Na [Ni0.25Fe0.5Mn0.25]O2) and two anode materials (Na15Sn4 and Na) thus allowing the implementation of four electrochemical stacks, all characterized as accumulators. Finally, the improvement of the interfaces thanks to a gel-polymer made it possible to improve the properties of the assemblies with notably an increase of the speeds of charge / discharge and an enhanced mobilization of the cathode active materials

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Pfeifer, Kristina [Verfasser], et H. [Akademischer Betreuer] Ehrenberg. « Reactivity and Interplay of Critical Components in Sodium-Ion Batteries / Kristina Pfeifer ; Betreuer : H. Ehrenberg ». Karlsruhe : KIT-Bibliothek, 2021. http://d-nb.info/1227451318/34.

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Mattsson, Agnes-Matilda, Towa Eriksson, Caroline Löwnertz et Marielle Holmbom. « Recycling of Prussian White ». Thesis, Uppsala universitet, Institutionen för kemi - Ångström, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-445281.

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The aim of this project was to find a recycling route for Prussian white. During the experimental part, one recycling method was tested using sodium hydroxide and from this a method for re-synthesis of Prussian white was conducted as well as a method for re-crystallisation of sodium ferrocyanide. The method that proved most successful was the re-crystallisation of sodium ferrocyanide. Furthermore, the conditions needed to conduct a proper re-synthesis of Prussian white was not available during this research. Therefore, it was not possible to produce Prussian white of the right structure. The analysis was performed through XRD analysis and it was concluded that it is possible to re-crystallise sodium ferrocyanide from Prussian white.

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Göktaş, Mustafa [Verfasser], Philipp [Gutachter] Adelhelm et Andrea [Gutachter] Balducci. « Graphite as co-intercalation host for sodium ion batteries / Mustafa Göktaş ; Gutachter : Philipp Adelhelm, Andrea Balducci ». Jena : Friedrich-Schiller-Universität Jena, 2019. http://d-nb.info/1207271713/34.

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Seidl, Lukas [Verfasser], Ulrich [Akademischer Betreuer] Stimming, Aliaksandr [Gutachter] Bandarenka et Ulrich [Gutachter] Stimming. « Sodium Ion Batteries - from Fundamentals to Application / Lukas Seidl ; Gutachter : Aliaksandr Bandarenka, Ulrich Stimming ; Betreuer : Ulrich Stimming ». München : Universitätsbibliothek der TU München, 2018. http://d-nb.info/1175582468/34.

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Li, Sheng. « Graphene-based Composites as Anode Materials for Rechargeable Batteries ». Thesis, Griffith University, 2015. http://hdl.handle.net/10072/367790.

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With increasing demand for low cost and high performance energy resources, rechargeable batteries, such as lithium ion batteries (LIBs) and sodium ion batteries (SIBs), have been intensively studied in recent years. The performance of existing anode materials for both LIBs and SIBs need substantial improvements in terms of energy capacity, rate capability, stability, safety and manufacturing cost to modernize the battery applications in electric vehicles (EV) and energy-saving smart electric grids. Graphene is considered an effective additive in fabricating composites for anode materials since it possesses high electrical conductivity, large surface area and excellent mechanical properties. Therefore, this thesis attempts to synthesize a series of graphene-based composites as anode materials for LIBs and SIBs, to address the aforementioned concerns. To date, numerous methods have been developed for the fabrication of graphene composites; however, most of them are sophisticated, complex, not scalable and therefore expensive. A wet-mechanochemical (wet ball-milling) method that is simple, rapid, facile, economic and most importantly, can be up-scaled for mass production is proposed to address these issues.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Science, Environment, Engineering and Technology
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Bečan, Jan. « Pokročilé uhlíkové struktury jako materiál pro Na-ion akumulátory ». Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2021. http://www.nusl.cz/ntk/nusl-442445.

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This diploma thesis deals with the description of individual types of batteries. The first part is focused to primary and secondary batteries, materials for their positive and negative electrodes with a focus on lithium-ion batteries and their changes over time. The next section focuses on a more detailed description of sodium-ion batteries, used electrode materials and to their problems. Practical part is focesed to preparing of electrode materials and to completing of measuring electrochemical cell and to discribing of measuring methodes and to evaluation of measured data.

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Sgarbi, Stabellini Francesca. « Synthesis and surface characterization of metal (Mn, Ti) hexacyanoferrate electrodes ». Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amslaurea.unibo.it/24378/.

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Due to the limited resources of lithium, new chemistries based on the abundant and cheap sodium and even zinc have been proposed for the battery market. Prussian Blue Analogues (PBAs) are a class of compounds which have been explored for many different applications because of their intriguing electrochemical and magnetic properties. Manganese and titanium hexacyanoferrate (MnHCF and TiHCF) belong to the class of PBAs. In this work, MnHCF and TiHCF electrodes were synthetized, cycled with cyclic voltammetry (CV) in different setups and subsequently, the surfaces were characterized with X-ray Photoelectron Spectroscopy (XPS). The setups chosen for CVs were coin cell with zinc aqueous solution for the MnHCF series, three-electrode cell and symmetric coin cell with sodium aqueous solution for the TiHCF series. The electrodes were treated with different number of cycles to evaluate the chemical changes and alterations in oxidation states during cycling.

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Liu, Xinye. « Binary metal organic framework derived hierarchical hollow Ni3S2/Co9S8/N-doped carbon composite with superior sodium storage performance ». University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron1489784678856585.

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Wasalathilake, Kimal Chandula. « Synthesis and characterization of modified graphene for energy storage applications ». Thesis, Queensland University of Technology, 2018. https://eprints.qut.edu.au/123800/1/Kimal_Wasalathilake_Thesis.pdf.

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This thesis presents the synthesis and characterization of modified graphene materials and investigates their role in sustainable energy storage applications by using both experimental methods and density functional theory simulations. The outcomes obtained provide a better understanding of the structure-property relationship in modified graphene and its role in electrochemical process in rechargeable batteries, benefiting the development of high-performance electrode materials.

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Kishore, Brij. « Electrochemical Investigations Related to the Next Generation Sodium and Potassium Batteries ». Thesis, 2017. http://etd.iisc.ac.in/handle/2005/4232.

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The commercialization of Li-ion battery (LIB) in 1990s by Sony Corporation has led to its applications in portable electronic devices such as mobile phones, cameras, laptop computers, etc. Initially, the energy density of commercial LIB was only about 120 Wh Kg-1. However, with sustained improvements in properties of various cell components, the present-day LIB provides energy density of about 250 Wh Kg-1. With future use envisaged for mobility applications such as electric vehicles, research activities have gained momentum for development of high energy density Li-S and Li-O2 batteries. However, due to limited sources of lithium (0.007 % in earth’s crust and 0.2 ppm in sea water) and uneven distribution, concerns arise about its cost and availability which would inhibit bulk production and utilization of lithium-based batteries. Hence, there is an urgent need to switch over to battery systems employing earth abundant and environmentally benign materials. Sodium and potassium-based batteries have received attention in research laboratories as alternatives to lithium-based batteries due to their natural abundance and low cost. Na and K are the metals below Li in the periodic table and their physical and chemical properties are similar to those of Li. Na and K are the sixth and seventh most abundant elements, constituting 2.6 % and 2.4 %, respectively of the earth’s crust. Sea water contains about 10800 ppm Na and 400 ppm K. Although, the standard potentials of Na/Na+ (-2.71 V vs. standard hydrogen electrode (SHE)) and K/K+ (-2.93 V vs. SHE) are less than Li/Li+ (-3.04 V vs. SHE) by about 300 and 100 mV, respectively, the cost and availability factors overweigh the marginal reduction in energy density. The quest for new electrode materials for Na- and K-based batteries, their physicochemical characterizations and electrochemical investigations are described in the thesis. It consists of a comprehensive review of the literature on the evolution of battery systems with a focus on the next generation Na- and K-based batteries. The cathode and anode materials for Na- and K-ion batteries are reviewed along with the current research activities in Na- and K-sulphur, and Na- and K-O2 batteries. It furnishes a brief description of various experimental techniques and procedures adopted at different stages of the present thesis. The amorphous MnO2 has been prepared by two different methods: (i) reduction of KMnO4 using ethylene glycol (EG) and (ii) the redox reaction between KMnO4 and MnSO4.H2O at ambient conditions. The as prepared MnO2 samples in both cases are amorphous in nature and on heating in the temperature range of 300 – 800 °C, they convert to α-MnO2. The MnO2 prepared by reduction by EG has been studied for Na/MnO2 and Li/MnO2 laboratory scale primary cells in non-aqueous electrolytes. The specific capacity of amorphous MnO2 is 300 mAh g-1 in both Na/MnO2 and Li/MnO2 cells. Na/MnO2 cell shows a nominal voltage less than Li/MnO2 cell by 0.35 V, as expected. MnO2 prepared by the redox reaction between KMnO4 and MnSO4.H2O has a specific surface area of 184 m2 g-1 with narrowly distributed mesopores of 3.5 nm pore diameter. The crystallinity increases and specific surface area decreases upon heating. The as prepared sample provides the first discharge capacity of about 300, 200 and 80 mAh g-1 for Li-, Na- and K-MnO2 cells, respectively, at a specific current of 50 mA g-1. The attractively high discharge capacity of the as prepared amorphous MnO2 is attributed to the large specific surface area and mesoporosity. However, the crystalline samples exhibit low specific discharge capacity in comparison with amorphous samples. It deals with electrochemical impedance spectroscopy (EIS) study of Na/MnO2 primary cell fabricated in a non-aqueous electrolyte of Na salt. The EIS data provides a high resistance of Na metal due to the surface passive film. On subjecting the cell for discharge, the surface film causes a delay response of the cell voltage and the closed-circuit voltage reaches the normal discharge level following dielectric break-down of the film. The EIS data measured at different stages of cell discharge are subjected to non-linear least squares fitting with the aid of an appropriate equivalent circuit. The impedance parameters are examined to throw light on state-of-charge of Na/MnO2 primary cells. The study has been further extended to analyze the delay-time behaviour of the non-aqueous Na/MnO2 cells and quantifying the film resistance and break-down field for the film formed on the Na surface. P2-type Na0.67Mn0.65Fe0.20Ni0.15O2 is studied as a cathode material for Na-ion battery and presented. It is synthesized in microspherical and disc-like morphologies using two different synthetic procedures. Microspheres of FeCO3 are first prepared and used as a template to synthesize Mn0.65Fe0.20Ni0.15CO3, followed by its thermal decomposition to the corresponding oxide and finally, thermal fusion of the oxide with Na2CO3 to produce P2-type Na0.67Mn0.65Fe0.20Ni0.15O2. However, disc-like Na0.67Mn0.65Fe0.20Ni0.15O2 is synthesized by sintering the product obtained using a low temperature solution combustion method using aqueous solution of stoichiometric quantities of corresponding metal nitrates and sucrose as the fuel at 800 °C. Cyclic voltammograms in both the samples are characterized by well-defined two pairs of current peaks corresponding to the oxidation and reduction processes in two different stages. The sodiated microspherical oxide provides an initial discharge capacity of about 216 mAh g-1 at C/15 rate cycling with an excellent cycling stability (Fig. 3a). The rate capability is also high, and the discharge capacity is about 100 mAh g-1 at 2C rate. The high discharge capacity and high rate capability are attributed to porous microspherical morphology. When the cells with disc-like morphology cathode sample are cycled at a current density of 35 mA g-1, a specific discharge capacity of 178 mAh g-1 is obtained with close to 100 % coulombic efficiency. Capacity retention of more than 70 % is observed after 50 charge-discharge cycles Potassium tetratitanate (K2Ti4O9) is synthesized by solid-state method using K2CO3 and TiO2 and studied as an anode material for potassium ion batteries (KIB) for the first time. A discharge capacity of 97 mAh g-1 has been obtained at a current density of 30 mA g-1 (0.2 C rate) and 80 mAh g-1 at 100 mA g-1 (0.8 C rate), initially (Fig. 4a). The proposed mechanism of charging involves reduction of two Ti ions from 4+ oxidation state to 3+ oxidation state, which facilitates insertion of two K+ ions per formula unit in the zig-zag layer of TiO6 octahedra separated with K+ ions with interlayer spacing of 0.85 nm. For KIB cathode, K0.27Mn0.65Fe0.35-xNixO2 (0.00 ≤ x ≤ 0.35) is synthesized in microspherical morphology. The potassiated mixed metal oxide formed in microspherical morphology is in pure crystalline phase. The oxide with the composition x = 0.35 i.e., K0.27Mn0.65Ni0.35O2 provides the highest first specific discharge capacity of 97 mAh g-1 at C/10 rate (Fig. 4b). A good cycling stability is observed. It deals with carbonization of milk-free coconut kernel pulp carried out at low temperatures. The carbon samples are activated using KOH and electrical doublelayer capacitor (EDLC) properties are studied (Fig. 5a). Among the several samples prepared, activated carbon prepared at 600 °C has a large specific surface area (1200 m2 g-1). Cyclic voltammetry and galvanostatic charge-discharge studies suggest that activated carbons derived from coconut kernel pulp are appropriate materials for EDLC studies in acidic, alkaline and non-aqueous electrolytes. Specific capacitance (SC) of 173 F g-1 is obtained in 1 M H2SO4 electrolyte for the activated carbon prepared at 600 °C. The supercapacitor properties of activated carbon sample prepared at 600 °C are superior to the samples prepared at higher temperatures. Electrochemical studies are also undertaken for the prepared and activated samples for sodium ion intercalation/deintercalation. It is found that various factors such as surface area, mesoporosity, inter-layer spacing, electrolyte diffusion, solid electrolyte interface formation for high surface area carbon, etc. contribute to the capacity and cycle life of the material. Carbon sample synthesized at 600 °C and having a specific surface area of about 280 m2 g-1 provides the highest discharge capacity of about 200 mAh g-1 with good cycling stability. The thesis ends with a short summary and prospects of the investigations described here in. The work presented in it is carried out by the candidate as a part of Int. Ph.D. program. Some of the results are published in the literature and some more manuscripts are in preparation. A list of publications is enclosed. It is hoped that the studies reported in the thesis are worthy contributions.

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Thèses sur le sujet « Sodium-ion batterie »

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