Дисертації з теми "Oxynitrure de phosphate de lithium"
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Bayzou, Racha. "Caractérisation par RMN de la structure à l'échelle atomique des couches minces de LiPON utilisées comme électrolyte dans les microbatteries." Electronic Thesis or Diss., Université de Lille (2022-....), 2022. http://www.theses.fr/2022ULILR056.
All-solid-state microbatteries are promising devices for a wide range of applications pertaining to communication, consumer electronics, products and people identification, traceability, security as well as the internet of things. Nevertheless, low ionic conductivity of the solid electrolytes remains a major limitation of these devices. In particular, lithium phosphorus oxynitride (LiPON), which is currently the commercial standard electrolyte for all-solid-state microbatteries, has a three-fold lower conductivity than liquid electrolytes used Li-ion batteries. The rational improvement of the conductivity of LiPON and its derivatives requires a better understanding of their atomic-scale structure and dynamics. In this thesis, we explored how solid-state NMR spectroscopy can be used to characterize the structure and atomic-scale dynamics of LiPON thin films. The NMR data were compared to those of electrochemical impedance spectroscopy to better understand the conduction mechanisms. In particular, we have shown that the ionic conductivity increases with the nitrogen content of LiPONs. This is due to the formation of bridging nitrogens, which less interact with Li+ ions than the apical nitrogens. This study was then extended to LiSiPON thin films in order to study the effect of the incorporation of silicon atoms on the structure and dynamics of LiPON. This thesis also focused on the development of new pulse sequences for the indirect detection of nuclei subject to large anisotropic interactions via other isotopes subject to small anisotropic interactions. The objective was notably to detect the 14N nuclei (with spin I = 1 and subject to quadrupole interactions of a few megahertz), via the 31P or 6,7Li nuclei. For that purpose, we have demonstrated the possibility to detect with low t1 noise the double-quantum coherences between the mI = +1 and −1 energy levels of 14N nuclei via protons in organic molecules, such as L-histidine-HCl, thanks to the HMQC sequence using a TRAPDOR recoupling. We have also demonstrated that T-HMQC experiment allows the indirect detection of spin-1/2 nuclei subject to large chemical shift anisotropy (CSA) via protons. Nevertheless, due to time constraints, we were not able to apply the T-HMQC sequence to the study of LiPON during this thesis
Popovic, Jelena. "Novel lithium iron phosphate materials for lithium-ion batteries." Phd thesis, Universität Potsdam, 2011. http://opus.kobv.de/ubp/volltexte/2011/5459/.
Konventionelle Energiequellen sind weder nachwachsend und daher nachhaltig nutzbar, noch weiterhin langfristig verfügbar. Sie benötigen Millionen von Jahren um gebildet zu werden und verursachen in ihrer Nutzung negative Umwelteinflüsse wie starke Treibhausgasemissionen. Im 21sten Jahrhundert ist es unser Ziel nachhaltige und umweltfreundliche, sowie möglichst preisgünstige Energiequellen zu erschließen und nutzen. Neuartige Technologien assoziiert mit transportablen Energiespeichersystemen spielen dabei in unserer mobilen Welt eine große Rolle. Li-Ionen Batterien sind in der Lage wiederholt Energie aus entsprechenden Prozessen nutzbar zu machen, indem sie reversibel chemische in elektrische Energie umwandeln. Die Leistung von Li-Ionen Batterien hängen sehr stark von den verwendeten Funktionsmaterialien ab. Aktuell verwendete Elektrodenmaterialien haben hohe Produktionskosten, verfügen über limitierte Energiespeichekapazitäten und sind teilweise gefährlich in der Nutzung für größere Bauteile. Dies beschränkt die Anwendungsmöglichkeiten der Technologie insbesondere im Gebiet der hybriden Fahrzeugantriebe. Die vorliegende Dissertation beschreibt bedeutende Fortschritte in der Entwicklung von LiFePO4 als Kathodenmaterial für Li-Ionen Batterien. Mithilfe einfacher Syntheseprozeduren konnten eine vollkommen neue Morphologie (mesokristallines LiFePo4) sowie ein nanostrukturiertes Material mit exzellenten elektrochemischen Eigenschaften hergestellt werden. Die neu entwickelten Verfahren zur Synthese von LiFePo4 sind einschrittig und bei signifikant niedrigeren Temperaturen im Vergleich zu konventionellen Methoden. Die Verwendung von preisgünstigen und umweltfreundlichen Ausgangsstoffen stellt einen grünen Herstellungsweg für die large scale Synthese dar. Mittels des neuen Synthesekonzepts konnte meso- und nanostrukturiertes LiFe PO4 generiert werden. Die Methode ist allerdings auch auf andere phospho-olivin Materialien (LiCoPO4, LiMnPO4) anwendbar. Batterietests der besten Materialien (nanostrukturiertes LiFePO4 mit Kohlenstoffnanobeschichtung) ergeben eine mögliche Energiespeicherung von 94%.
Myalo, Zolani. "Graphenised Lithium Iron Phosphate and Lithium Manganese Silicate Hybrid Cathode Systems for Lithium-Ion Batteries." University of the Western Cape, 2017. http://hdl.handle.net/11394/6036.
This research was based on the development and characterization of graphenised lithium iron phosphate-lithium manganese silicate (LiFePO4-Li2MnSiO4) hybrid cathode materials for use in Li-ion batteries. Although previous studies have mainly focused on the use of a single cathode material, recent works have shown that a combination of two or more cathode materials provides better performances compared to a single cathode material. The LiFePO4- Li2MnSiO4 hybrid cathode material is composed of LiFePO4 and Li2MnSiO4. The Li2MnSiO4 contributes its high working voltage ranging from 4.1 to 4.4 V and a specific capacity of 330 mA h g-1, which is twice that of the LiFePO4 which, in turn, offers its long cycle life, high rate capacity as well as good electrochemical and thermal stability. The two cathode materials complement each other's properties however they suffer from low electronic conductivities which were suppressed by coating the hybrid material with graphene nanosheets. The synthetic route entailed a separate preparation of the individual pristine cathode materials, using a sol-gel protocol. Then, the graphenised LiFePO4-Li2MnSiO4 and LiFePO4-Li2MnSiO4 hybrid cathodes were obtained in two ways: the hand milling (HM) method where the pristine cathodes were separately prepared and then mixed with graphene using a pestle and mortar, and the in situ sol-gel (SG) approach where the Li2MnSiO4 and graphene were added into the LiFePO4 sol, stirred and calcined together.
2021-04-30
Hsiung, Chwan Hai H. (Chwan Hai Harold) 1982. "Synthesis and electrochemical characterization of lithium vanadium phosphate." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/32730.
Includes bibliographical references (leaf 41).
In a world where the miniaturization and the portability of electronic devices is king, batteries play an ever-increasingly important role. They are vital components in many consumer electronics such as cell phones and PDAs, in medical devices, and in novel applications, such as unmanned vehicles and hybrids. As the power demands of these devices increases, battery performance must improve accordingly. This thesis is an introductory investigation into the electrochemical properties of a promising new battery cathode material: lithium vanadium phosphate (Li3V2(PO4)3) (LVP). Studies of other members of the phospho-olivine family, which LVP is a part of, indicate that the olivines have high lithium diffusivity but low electronic conductivity. LVP is part of the phosphor- olivine family, which traditionally has been shown to have high lithium diffusivity but low electronic conductivity. LVP was synthesized via a solid-state reaction and cast into composite cathodes. (90/5/5 ratio of LVP, Super P Carbon, and PVDF.) These composite cathodes were used in lithium anode, LiPF6 liquid electrolyte, Swage-type cells that were galvanostatically cycled from 3.OV to 4.2V and from 3.4V to 4.8V at C/20 rates. Electrochemical impedance spectroscopy was carried out on an LVP / liquid electrolyte / LVP cells from 0.01Hz to 1MHz. Finally, temperature conductivity measurements were taken from a die-pressed LVP bar. The results of the experimentation indicate that LVP has much promise as a new battery cathode material, but there are still a number of concerns to address.
(cont.) LVP has a higher operating voltage (4.78V) than the current Li-ion battery standard (3.6V), but there are issues with becoming amorphous, cycleability, and active material accessibility. From the EIS data, passivating films on the surface of the LVP cathode do not seem to be a factor in limiting performance. The conductivity data gives a higher than expected conductivity (4.62* 10-4 S/cm).
by Chwan Hai H. Hsiung.
S.B.
Popovi´c, Jelena [Verfasser], and Markus [Akademischer Betreuer] Antonietti. "Novel lithium iron phosphate materials for lithium-ion batteries / Jelena Popovi´c. Betreuer: Markus Antonietti." Potsdam : Universitätsbibliothek der Universität Potsdam, 2011. http://d-nb.info/1016576242/34.
Perea, Alexis. "Les phosphates de structure olivine LiMPO4 (M=Fe, Mn) comme matériau actif d’électrode positive des accumulateurs Li-ion." Thesis, Montpellier 2, 2011. http://www.theses.fr/2011MON20074/document.
This thesis is devoted to finding positive electrode materials for Li-ion batteries and more particularlycompounds of olivine type: LiFePO4, LiFe1-yMnyPO4, LiFe1-yCoyPO4 and LiMnyCo1-yPO4. An in-depth study of their physicochemical and structural properties was done combining Solid State Chemistry and Material Sciences techniques: Mössbauer spectrometry of 57Fe, microscopy SEM and X-ray diffraction. The aim of this study is to identify and understand the electrochemical mechanism during the cycling of the battery that can enhance or limit the battery performance. This study has shown the complementarity of Mössbauer spectrometry and X-ray diffraction to analyze the redox mechanisms involved into the electrochemical reactions. From the well-known two-phase mechanism of LiFePO4, electrochemical mechanisms in three steps and phases formed during cycling have been identified for phase substituted manganese. The ability of these compounds to be used as positive electrode materials for powerful Li-Ion batteries was demonstrated by long-term cycling at different temperatures and rates of cycling
Möller, Alexander [Verfasser]. "Study of the mechanism of lithium insertion and depletion in lithium iron phosphate thin films / Alexander Möller." Gießen : Universitätsbibliothek, 2014. http://d-nb.info/106887449X/34.
Kolesnikov-Lindsey, Rachel. "Virus constructed iron phosphate lithium ion batteries in unmanned aircraft systems." Thesis, Massachusetts Institute of Technology, 2010. https://hdl.handle.net/1721.1/122859.
Cataloged from PDF version of thesis. "September 2010."
Includes bibliographical references (pages 48-49).
Since lithium ion batteries first became commercially available in 1991, they have been repeatedly improved, continually redefining just how much we can do with electronic devices. Today, battery powered Unmanned Aerial Systems (UAS) the size of a model plane such as the Raven allow soldiers to see dangerous situations and potential threats without ever needing to enter the area and put their lives in danger. This technology is saving lives and redefining warfare. However, the Raven and other UAS are limited by the amount of time they are able to spend in the air and quality of the cameras they can power. This thesis focuses on the scale up of FePO₄ lithium ion batteries that have cathodes constructed by viruses with the purpose of using them as an auxiliary battery in the Raven to power the payload equipment. These batteries are assembled at standard temperature and pressure, yet are consistently able to achieve 20nm FePO 4 particle size, creating higher energy density. A prototype auxiliary battery design is created, tested, and refined to determine how virally constructed FePO₄ batteries behave as they are scaled up.
by Rachel Kolesnikov-Lindsey.
M. Eng.
M.Eng. Massachusetts Institute of Technology, Department of Materials Science and Engineering
Volk, Martin [Verfasser]. "Optical ridge waveguides in lithium niobate and potassium titanyl phosphate / Martin Volk." Hamburg : Helmut-Schmidt-Universität, Bibliothek, 2019. http://d-nb.info/1179197119/34.
Sifuba, Sabelo. "Electrochemically enhanced ferric lithium manganese phosphate / multi-walled carbon nanotube, as a possible composite cathode material for lithium ion battery." University of the Western Cape, 2019. http://hdl.handle.net/11394/7077.
Lithium iron manganese phosphate (LiFe0.5Mn0.5PO4), is a promising, low cost and high energy density (700 Wh/kg) cathode material with high theoretical capacity and high operating voltage of 4.1 V vs. Li/Li+, which falls within the electrochemical stability window of conventional electrolyte solutions. However, a key problem prohibiting it from large scale commercialization is its severe capacity fading during cycling. The improvement of its electrochemical cycling stability is greatly attributed to the suppression of Jahn-Teller distortion at the surface of the LiFe0.5Mn0.5PO4 particles. Nanostructured materials offered advantages of a large surface to volume ratio, efficient electron conducting pathways and facile strain relaxation. The LiFe0.5Mn0.5PO4 nanoparticles were synthesized via a simple-facile microwave method followed by coating with multi-walled carbon nanotubes (MWCNTs) nanoparticles to enhance electrical and thermal conductivity. The pristine LiFe0.5Mn0.5PO4 and LiFe0.5Mn0.5PO4-MWCNTs composite were examined using a combination of spectroscopic and microscopic techniques along with electrochemical techniques such as cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Microscopic results revealed that the LiFe0.5Mn0.5PO4-MWCNTs composite contains well crystallized particles and regular morphological structures with narrow size distributions. The composite cathode exhibits better reversibility and kinetics than the pristine LiFe0.5Mn0.5PO4 due to the presence of the conductive additives in the LiFe0.5Mn0.5PO4-MWCNTs composite. For the composite cathode, D = 2.0 x 10-9 cm2/s while for pristine LiFe0.5Mn0.5PO4 D = 4.81 x 10-10 cm2/s. The charge capacity and the discharge capacity for LiFe0.5Mn0.5PO4-MWCNTs composite were 259.9 mAh/g and 177.6 mAh/g, respectively, at 0.01 V/s. The corresponding values for pristine LiFe0.5Mn0.5PO4 were 115 mAh/g and 44.75 mAh/g, respectively. This was corroborated by EIS measurements. LiFe0.5Mn0.5PO4-MWCNTs composite showed to have better conductivity which corresponded to faster electron transfer and therefore better electrochemical performance than pristine LiFe0.5Mn0.5PO4. The composite cathode material (LiFe0.5Mn0.5PO4-MWCNTs) with improved electronic conductivity holds great promise for enhancing electrochemical performances and the suppression of the reductive decomposition of the electrolyte solution on the LiFe0.5Mn0.5PO4 surface. This study proposes an easy to scale-up and cost-effective technique for producing novel high-performance nanostructured LiFe0.5Mn0.5PO4 nano-powder cathode material.
2023-12-01
Ohira, Koji. "Systematic survey of phosphate materials for lithium-ion batteries by first principle calculations." Master's thesis, 京都大学 (Kyoto University), 2013. http://hdl.handle.net/2433/180500.
Yaddanapudi, Anurag. "Fabrication and characterizations of lithium aluminum titanate phosphate solid electrolytes for Li-based batteries." Wright State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=wright1547044605448066.
Toledano, Elie. "Régulation de la poly (ADP-Ribose) Polymérase par le phosphoadénosine phosphate." Paris 6, 2011. http://www.theses.fr/2011PA066597.
Hlongwa, Ntuthuko Wonderboy. "Nanoparticles-infused lithium manganese phosphate coated with magnesium-gold composite thin film - a possible novel material for lithium ion battery olivine cathode." University of the Western Cape, 2014. http://hdl.handle.net/11394/4467.
Architecturally enhanced electrode materials for lithium ion batteries (LIB) with permeable morphologies have received broad research interests over the past years for their promising properties. However, literature based on modified porous nanoparticles of lithium manganese phosphate (LiMnPO₄) is meagre. The goal of this project is to explore lithium manganese phosphate (LiMnPO₄) nanoparticles and enhance its energy and power density through surface treatment with transition metal nanoparticles. Nanostructured materials offer advantages of a large surface to volume ratio, efficient electron conducting pathways and facile strain relaxation. The material can store lithium ions but have large structure change and volume expansion during charge/discharge processes, which can cause mechanical failure. LiMnPO₄ is a promising, low cost and high energy density (700 Wh/kg) cathode material with high theoretical capacity and high operating voltage of 4.1 V vs. Ag/AgCl which falls within the electrochemical stability window of conventional electrolyte solutions. LiMnPO₄ has safety features due to the presence of a strong P–O covalent bond. The LiMnPO₄ nanoparticles were synthesized via a sol-gel method followed by coating with gold nanoparticles to enhance conductivity. A magnesium oxide (MgO) nanowire was then coated onto the LiMnPO₄/Au, in order to form a support for gold nanoparticles which will then form a thin film on top of LiMnPO₄ nanoparticles crystals. The formed products will be LiMnPO₄/Mg-Au composite. MgO has good electrical and thermal conductivity with improved corrosion resistance. Thus the electronic and optical properties of MgO nanowires were sufficient for the increase in the lithium ion diffusion. The pristine LiMnPO₄ and LiMnPO₄/Mg-Au composite were examined using a combination of spectroscopic and microscopic techniques along with cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Microscopic results revealed that the LiMnPO₄/Mg-Au composite contains well crystallized particles and regular morphological structures with narrow size distributions. The composite cathode exhibits better reversibility and kinetics than the pristine LiMnPO₄ due to the presence of the conductive additives in the LiMnPO₄/Mg-Au composite. This is demonstrated in the values of the diffusion coefficient (D) and the values of charge and discharge capacities determined through cyclic voltammetry. For the composite cathode, D= 2.0 x 10⁻⁹ cm²/s while for pristine LiMnPO₄ D = 4.81 x 10⁻¹⁰ cm2/s. The charge capacity and the discharge capacity for LiMnPO₄/Mg-Au composite were 259.9 mAh/g and 157.6 mAh/g, respectively, at 10 mV/s. The corresponding values for pristine LiMnPO₄ were 115 mAh/g and 44.75 mAh/g, respectively. A similar trend was observed in the results obtained from EIS measurements. These results indicate that LiMnPO₄/Mg-Au composite has better conductivity and will facilitate faster electron transfer and therefore better electrochemical performance than pristine LiMnPO₄. The composite cathode material (LiMnPO₄/Mg-Au) with improved electronic conductivity holds great promise for enhancing electrochemical performances, discharge capacity, cycle performance and the suppression of the reductive decomposition of the electrolyte solution on the LiMnPO₄ surface. This study proposes an easy to scale-up and cost-effective technique for producing novel high-performance nanostructured LiMnPO₄ nanopowder cathode material.
Badyal, Rajji Rani. "Structural and functional studies on bovine inositol monophosphatase." Thesis, University of Southampton, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.342652.
Dupré, Nicolas. "Etude du phosphate de vanadyle comme matériau d'électrode de batteries Li-ion." Paris 6, 2001. http://www.theses.fr/2001PA066420.
Dong, Trung-Kien. "Contribution à la modélisation dynamique des batteries Lithium-ion pour l’application photovoltaïque et stockage connecté au réseau." Grenoble INPG, 2010. http://www.theses.fr/2010INPG0066.
The aim of the thesis is the dynamic modelling of Lithium Iron Phosphate j Graphite (LiFeP04c) batteries. The work is part of the studies aiming to adapt new energy storage technologies for the photovoltaic applications. The developed model is also applicable for the simulation of Li-ion battery operation under electric vehicle profiles. Electrochemical Impedance Spectroscopy (EIS) measurements on LiFeP04C batteries show a good correlation with the EIS of Li-ion batteries found in the literature, and thus the known Equivalent Electrical Circuit model of Li-ion batteries has been used in the present mode!. Full ' parameterization of EEC models is not possible only with the EIS method and, therefore, a combined frequencyjtemporal method has been developed. An excellent correlation between simulated and measured date was observed in wide State Of Charge and chargejdischarge current range
Herstedt, Marie. "Towards Safer Lithium-Ion Batteries." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-3542.
Riviere, Elie. "Détermination in-situ de l'état de santé de batteries lithium-ion pour un véhicule électrique." Thesis, Université Grenoble Alpes (ComUE), 2016. http://www.theses.fr/2016GREAI048/document.
Accurate lithium-ion battery State of Charge (SoC) and State of Health (SoH) estimations are nowadays a crucial point, especially when considering an industrial use. These estimations enable to improve robustness and reliability of hardware using such batteries. This thesis focuses on researching lithium-ion batteries state of health estimators, in particular considering Lithium Iron Phosphate (LFP) and Lithium Manganese Oxide (LMO) chemistries.Researches have been targeted towards SoH estimators straight embeddable into electric vehicles (EV) computers. Cost and reliability constraints are thus the main guideline for this work.Although existing literature offers various SoH estimators, those who are embedded or embeddable are still little studied. A complete literature review about SoH estimators, embedded or not, is therefore proposed. Lithium-ion batteries detailed operation and ageing mechanisms are also presented.The main part of this work is dedicated to Incremental Capacity Analysis (ICA) use with electric vehicle constraints, such as current levels available with a typical EV mission profile or existing measurements on the Battery Management System (BMS). Incremental Capacity Analysis is implemented in an innovative way and leads to a remaining capacity estimator with a high robustness to conditions of use variations, including an extended temperature range.A second method, dedicated to LMO chemistry, take advantage of the fact that the battery potential is representative of its state of charge. Partial Coulomb counting is thus performed, with a dynamic management of integration limits, depending on the battery state.Outcomes of this work are two complete and accurate SoH estimators, one for each chemistry, leading to a remaining capacity estimation accurate within 4 %
Cui, Yuantao [Verfasser], and H. J. [Akademischer Betreuer] Seifert. "Phosphate based ceramic as solid-state electrolyte for lithium ion batteries / Yuantao Cui ; Betreuer: H. J. Seifert." Karlsruhe : KIT-Bibliothek, 2018. http://d-nb.info/1170230482/34.
Zhang, Yin. "Study on electronic structure and rate performance of olivine phosphate cathode materials." Thesis, Queensland University of Technology, 2020. https://eprints.qut.edu.au/201911/1/Yin_Zhang_Thesis.pdf.
Lee, Chong-Hoon. "Study of reversible electrode reaction and mixed ionic and electronic conduction of lithium phosphate electrolyte for an electrochemical CO₂ gas sensor." Columbus, Ohio Ohio State University, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1073047249.
Title from first page of PDF file. Document formatted into pages; contains xvi, 149 p.; also includes graphics (some col.). Includes abstract and vita. Advisor: Sheikh Akbar, Dept. of Materials Science and Engineering. Includes bibliographical references (p. 138-149).
Stjerndahl, Mårten. "Stability Phenomena in Novel Electrode Materials for Lithium-ion Batteries." Doctoral thesis, Uppsala University, Department of Materials Chemistry, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-8214.
Li-ion batteries are not only a technology for the future, they are indeed already the technology of choice for today’s mobile phones, laptops and cordless power tools. Their ability to provide high energy densities inexpensively and in a way which conforms to modern environmental standards is constantly opening up new markets for these batteries. To be able to maintain this trend, it is imperative that all issues which relate safety to performance be studied in the greatest detail. The surface chemistry of the electrode-electrolyte interfaces is intrinsically crucial to Li-ion battery performance and safety. Unfortunately, the reactions occurring at these interfaces are still poorly understood. The aim of this thesis is therefore to increase our understanding of the surface chemistries and stability phenomena at the electrode-electrolyte interfaces for three novel Li-ion battery electrode materials.
Photoelectron spectroscopy has been used to study the surface chemistry of the anode material AlSb and the cathode materials LiFePO4 and Li2FeSiO4. The cathode materials were both carbon-coated to improve inter-particle contact. The surface chemistry of these electrodes has been investigated in relation to their electrochemical performance and X-ray diffraction obtained structural results. Surface film formation and degradation reactions are also discussed.
For AlSb, it has been shown that most of the surface layer deposition occurs between 0.50 and 0.01 V vs. Li°/Li+ and that cycling performance improves when the lower cut-off potential of 0.50 V is used instead of 0.01 V. For both LiFePO4 and Li2FeSiO4, the surface layer has been found to be very thin and does not provide complete surface coverage. Li2CO3 was also found on the surface of Li2FeSiO4 on exposure to air; this was found to disappear from the surface in a PC-based electrolyte. These results combine to give the promise of good long-term cycling with increased performance and safety for all three electrode materials studied.
Lainé-Cessac, Pascale. "La pyridoxal kinase erythrocytaire humaine : son activation par les ions potassium, sodium, lithium ; son inhibition par les medicaments." Angers, 1996. http://www.theses.fr/1996ANGE0507.
Höwing, Jonas. "The Challenge of Probing Lithium Insertion Mechanisms in Cathode Materials." Doctoral thesis, Uppsala University, Department of Materials Chemistry, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-4055.
The Li-ion battery has, from its commercialisation in the early 1990's, now become the most widely used power source for portable low-power electronics: laptops, cellular phones and MP3-players are a few examples. To further develop existing and find new electrode materials for these batteries, it is vital to understand the lithium insertion/extraction mechanisms taking place during battery operation. In this thesis, single-crystal X-ray diffraction has been used to investigate lithium insertion/extraction mechanisms in the cathode materials V6O13 and LiFePO4. A novel single-crystal electrochemical cell for in situ single-crystal X-ray diffraction studies has also been developed.
The phases Li3V6O13 and Li3+xV6O13, 0
Lithium has also been electrochemically extracted from LiFePO4 single crystals. On the basis of the shapes of the LiFePO4 and FePO4 reflections, it is concluded that FePO4 is formed at the crystal surface and that the LiFePO4/FePO4 interface propagates into the crystal. This is in agreement with an earlier proposed model for lithium extraction from LiFePO4 particles.
Initial experiments with the newly developed single-crystal electrochemical cell for in situ single-crystal X-ray diffraction demonstrate that it is possible to insert lithium into a single crystal of V6O13 and then collect single-crystal X-ray diffraction data. The method needs further development but promises to become a powerful tool for studying lithium insertion/extraction mechanisms.
Lee, Chong-Hoon. "Study of reversible electrode reaction and mixed ionic and electronic conduction of lithium phosphate electrolyte for an electrolchemical co2 gas sensor." The Ohio State University, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=osu1073047249.
Wong, Alexander T. "A Techno-Economic Analysis of Employing Lithium Iron Phosphate Battery Energy Storage System for Peak Demand Reduction of Industrial Manufacturing System." Case Western Reserve University School of Graduate Studies / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=case1613159189785232.
Yang, Jianping. "Synthesis and Characterizations of Lithium Aluminum Titanium Phosphate (Li1+xAlxTi2-x(PO4)3) Solid Electrolytes for All-Solid-State Li-ion Batteries." Wright State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=wright151550285784082.
Yu, Shicheng Verfasser], Rüdiger-A. [Akademischer Betreuer] [Eichel, and Ulrich [Akademischer Betreuer] Simon. "Development of a monolithic bulk-type all-solid-state lithium-ion battery based on phosphate materials / Shicheng Yu ; Rüdiger-Albert Eichel, Ulrich Simon." Aachen : Universitätsbibliothek der RWTH Aachen, 2017. http://d-nb.info/1169755275/34.
Yu, Shicheng [Verfasser], Rüdiger-A. [Akademischer Betreuer] Eichel, and Ulrich [Akademischer Betreuer] Simon. "Development of a monolithic bulk-type all-solid-state lithium-ion battery based on phosphate materials / Shicheng Yu ; Rüdiger-Albert Eichel, Ulrich Simon." Aachen : Universitätsbibliothek der RWTH Aachen, 2017. http://d-nb.info/1169755275/34.
Elfakir, Ammy. "Contribution à l'étude de l'orthophosphate de lithium en présence de métaux divalents." Rouen, 1986. http://www.theses.fr/1986ROUES002.
Nytén, Anton. "Low-Cost Iron-Based Cathode Materials for Large-Scale Battery Applications." Doctoral thesis, Uppsala University, Department of Materials Chemistry, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6842.
There are today clear indications that the Li-ion battery of the type currently used worldwide in mobile-phones and lap-tops is also destined to soon become the battery of choice in more energy-demanding concepts such as electric and electric hybrid vehicles (EVs and EHVs). Since the currently used cathode materials (typically of the Li(Ni,Co)O2-type) are too expensive in large-scale applications, these new batteries will have to exploit some much cheaper transition-metal. Ideally, this should be the very cheapest - iron(Fe) - in combination with a graphite(C)-based anode. In this context, the obvious Fe-based active cathode of choice appears to be LiFePO4. A second and in some ways even more attractive material - Li2FeSiO4 - has emerged during the course of this work.
An effort has here been made to understand the Li extraction/insertion mechanism on electrochemical cycling of Li2FeSiO4. A fascinating picture has emerged (following a complex combination of Mössbauer, X-ray diffraction and electrochemical studies) in which the material is seen to cycle between Li2FeSiO4 and LiFeSiO4, but with the structure of the original Li2FeSiO4 transforming from a metastable short-range ordered solid-solution into a more stable long-range ordered structure during the first cycle. Density Functional Theory calculations on Li2FeSiO4 and the delithiated on LiFeSiO4 structure provide an interesting insight into the experimental result.
Photoelectron spectroscopy was used to study the surface chemistry of both carbon-treated LiFePO4 and Li2FeSiO4 after electrochemical cycling. The surface-layer on both materials was concluded to be very thin and with incomplete coverage, giving the promise of good long-term cycling.
LiFePO4 and Li2FeSiO4 should both be seen as highly promising candidates as positive-electrode materials for large-scale Li-ion battery applications.
Moez, Charlotte. "Étude des propriétés électrochimiques de nouveaux matériaux nanostructurés à base de fer préparés par chimie douce et utilisables comme électrode positive d'accumulateurs au lithium." Paris 11, 2007. http://www.theses.fr/2007PA112096.
In the search for new positive electrode materials for lithium batteries, iron compounds are interesting due to their low cost and toxicity. For this purpose, b-FeOOH, g-FeOOH and LiFePO4 were studied. For oxyhydroxides, direct addition of acetylene black or carbon nanotubes (for the improvement of the electronic conductivity) was developed, which leads to non-uniform deposition and isolation of the grains, unfavorable for lithium insertion. A partial substitution of iron by cobalt was performed (improvement of the ionic conductivity). A stabilization of the exchangeable quantity of lithium is obtained with an optimum. For LiFePO4, several synthesis modes were performed (hydrothermal, mechanical activation, coprecipitation) to obtain different particles sizes. The electronic conductivity is enhanced by generation of a carbon layer onto the particles from thermal degradation of a carbohydrate. It appears that the finest the particles are, the best the insertion is. Crystallographic structural defects (observed by magnetic measurements) are favorable. The effect of carbon coating was studied with different carbon sources (starch, cellulose, carbon nanotubes, polyacrilonitril). The best compromise is achieved with cellulose: sp2 form (conductive carbon), covering (good electron percolation) and homogeneous (non rough surface)
Jaclyn and 李潔莉. "Surface synthesis of poly(3,4-ethylenedioxythiophene) on lithium iron phosphate for lithium ion battery." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/77391281371996450653.
國立成功大學
化學工程學系碩博士班
98
Lithium iron phosphate (LiFePO4) is material used in lithium ion battery as positive electrode material which has excellent thermal stability, good safety property, and environmentally friendly. In spite of these advantages, LiFePO4 has low conductivity and thereby its electrochemical performance is limited, resulting in poor rate capability. Poly(3,4-ethylenedioxythiophene) (PEDOT) is a conductive polymer which can be synthesized using chemical oxidation. Coating LiFePO4 with PEDOT conducting polymer can enhances the conductivity and rate capability. PEDOT had been successfully synthesized on the surface of LiFePO4 using UV radical polymerization or using metal ion as an oxidant. EDOT oxidizes to PEDOT while transferring electron reducing metal ion to metal. Metal ions which can oxidize EDOT are auric and ferric ion. Auric ion reduces to gold metal while ferric ion reduces to ferrous ion. When using ferric ion as oxidant, ferrous ion needs to be washed clearly. Ferrous ion could play a catalytic role in the formation and growth of an interfacial film between electrolyte and electrode. The best ferric ion used to oxidize EDOT is iron (III) tosylate (Fe(OT)3) because the resulting PEDOT contains least contaminant. When using auric ion as oxidant, high concentration EDOT (8 mmol) and low concentration HAuCl4 (25 mmol) sample gives the best performance on electrochemical test. Higher concentration of HAuCl4 can enhance the conductivity of LiFePO4 but no enhancement on electrochemical performance because the amount of active material in electrochemical test, which is LiFePO4, was reduced when there is too much gold in the composite. PEDOT synthesized from UV radical polymerization or using metal ion as an oxidant, all can enhance the conductivity, discharge capacity, and cycling ability of LiFePO4.
Wu, Shao-tzu, and 吳紹慈. "Hydrothermal Synthesis of Lithium Iron Phosphate without Reducing Additives." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/wq39e7.
國立中山大學
化學系研究所
102
LiFePO4 is successfully prepared by hydrothermal synthesis in air without extra reducing additives. The structure and morphology of the resulting LiFePO4 powders were shown by X-ray diffraction (XRD),scanning electron microscope (SEM), and a transmission electron microscope (TEM).The XRD results demonstrate that LiFePO4 powder has an orthorhombic olivine-type structure with a space group of Pnma. Raman spectroscopy and electron spectroscopy for chemical analysis (ESCA) reveal the impurity of Fe3+ in samples. The chemical composition of the LiFePO4 powders was characterized by elemental analysis (EA). Among the conditions, the electrochemical results show the energy capacity is 84 mAh g−1 at 0.2 C-rate.
Lin, Zih-Yeh, and 林子業. "Capacity analysis of cycling-used Lithium iron phosphate battery." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/00822478684989670169.
國立臺灣大學
工程科學及海洋工程學研究所
103
Human economic activities have been deeply impacted by oil crisis and global warming. Under such circumstances, industries related to Lithium iron phosphate (LiFePO4) battery have prospered greatly recently. LiFePO4 batteries have properties such as higher power, higher capacity, longer life-time and safer than other batteries. They are also widely used in electric buses, electric cars, hybrid electric cars, electric bicycles and energy storage devices. However, battery performance decreases with increasing cycle of usage. In order to investigate the relationship between cycle of usage and aging of battery, this thesis entrusts Phoenix Silicon International Corporation to discharge and charge the batteries cyclically by using battery automation test systems, and have the data saved simultaneously. Since the battery capacity curve varies with different conditions of battery, this thesis will adopt different kinds of curve fitting according to the conditions of the battery. We expect to accurately predict the battery capacity with the parameterized results, and also analyze the difference between experimental curve and fitted curve. In conclusion, this thesis will show the relationship between battery capacity and cycle of usage.
Peng, Shao-Wei, and 彭紹瑋. "The Study of Lithium Iron Manganese Phosphate Based Powders." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/psaegd.
Dodd, Joanna Lynn. "Phase composition and dynamical studies of lithium iron phosphate." Thesis, 2007. https://thesis.library.caltech.edu/1662/1/JoannaDodd_thesis.pdf.
Liang, Yi-Ping, and 梁毅平. "Ambient Hydrothermal Synthesis of Lithium Iron Phosphate and Its Electrochemical Properties in Lithium-ion Batteries." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/61601068701246452208.
國立中山大學
化學系研究所
100
Lithium iron phosphate (LiFePO4) has been synthesized by hydrothermal synthesis using pyrrole as an efficient reducing agent. The oxidized Fe3+ in the system reacts with pyrrole that can form polypyrrole (PPy) to generate Fe2+. The PPy can also be a carbon source for further calcination. The observations of scanning electron microscope (SEM) and transmission electron microscope (TEM) show that the particle size of LiFePO4 is around 500 nm and a layer of carbon coats on LiFePO4. The chemical composition of the LiFePO4 was characterized by elemental analysis (EA) and inductively coupled plasma mass spectroscopy (ICP/MS). The results of TEM and X-ray diffraction (XRD) show the structure of LiFePO4 is orthorhombic olivine. Raman and X-ray photoelectron spectroscopy (XPS) results indicate that pyrrole as a reducing agent prevents the impurity of Fe3+ formation and the resulting polypyrrole plays a role as carbon source. The calcination of LiFePO4 greatly affects the energy density. In addition, the carbon contain in the LiFePO4 powder is controllable using the addition of Fe3+ to enhance the electrical conductivity. Moreover, the electrochemical results show the energy capacity of the hydrothermal LiFePO4 is 152 mAh g−1. The LiFePO4 has a better rate discharge capability compared with LiFePO4 synthesized with ascorbic acid as a reducing agent.
Wen, Cheng-Han, and 温承翰. "The Study of Lithium Vanadium Phosphate Battery with Polymer Electrolyte." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/8n899e.
國立中興大學
奈米科學研究所
102
Cathode material lithium vanadium phosphate (Li3V2(PO4)3) is synthesized through sol-gel route followed by high temperature sintering. The lithium ion batteries in this study are composed of metallic lithium as anode and polymer gel electrolyte that mixed with different amounts of α-Al2O3 nanoparticles. For the batteries using liquid electrolyte, a stable charge capacity 128mAh / g is obtained during the charge-discharge process for recycling 50 times. For the gel electrolyte batteries, we found that the charge and discharge capacities can be improved by adding α-Al2O3 particles. The highest charge voltage for gel electrolyte batteries is 4.7V which corresponds to charge three lithium ions. However, the charge capacity is decreased with the numbers of charge-discharge cycles. The stability of charge-discharge is improved by setting charging limit to 4.3V which corresponds to charge two lithium ions. The analysis of the AC impedance results indicates that adding α-Al2O3 can reduce the charge transfer resistance.
Hung, Hao Ken, and 洪浩肯. "The study of lithium manganese-based phosphate powders and precursors." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/dep9u3.
Lin, Ming-Chieh, and 林明傑. "Study on Key Successful Factors of Lithium Iron Phosphate Battery." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/ee7y2q.
逢甲大學
經營管理碩士在職專班
103
International crude oil prices keep rising under the unstable condition of global economic recovery due to climate change and global warming. In 2011, Japan’s 311 earthquake cause the radiation exposure and people’s panic. A lot of nations vigorously promote low-carbon economic whick is high efficiency and low carbon emission. In order to seek opportunities of green industy, they positively develop the low-carbon technology and significant adjust the policy about industy, energy, technology and trading. We usually explan the energy as the resources which are included the energy solar energy, water energy, wind energy, wave energy, nuclear energy, thermal energy, geothermal energy or tidal energy. Traditional energy such as oil, coal will produce a lot of CO2. Althought the raw material fee of nuclear energy is low, the safe disposal of nuclear waste is a major problem. The dis-continuous supply of wind/water/solar energy can not necessarily meeting the requirement of each region. The importance of storage of energy is relatively high when it is different between the storage capacity and usage amount. The day peak-time and summer-season demand is high, so we need a smart storage system to keep the energy-produce system stable. Like some resvoirs transport water in low place to high place at night, they transfer electrical energy to potential energy. We call the name “battery” as the electrical energy storage. The battery storage energy through transfering electrical energy to chemical energy and release energy through transfering the chemical energy to the electrical energy. Primary battery is not rechargeable, and secondary battery is rechargeable. The characteristics of battery are voltage, current, energy density, rate. The common used types of battery are lead acid battery, nickel-cadmium battery, lithium battery, etc. The advantage of lithium battery is high energy density and has no pollution of heavy metal. The advantage of lithium iron phosphate is the stability of olivine structure and no risk of explosion. The lithium ion phosphate is gradually used in the device of electric vehicle. At present, the patents about LFP materials are grasped by A123 / Phostech / Aleees. You have to obtain the authorization to product the LFP material. The electrical power demand and car usage increase with the industry development. People gradually accept the electrical vehicle in order to reduce the pollution of engine vehicle, and wish the battery of electrical vehicle has the advantages of low price, high performance, large capacity, and high-speed charge ability. The advantages also can improve the balance of power usage such as peak-time power usage. The company can also set up power station to avoid the loss caused by suddenly power outages. In 2010, U.S. Senate passed proposed law to expect half of lightweight vehicles transfer to electric vehicles, and reduce the one third demand of oil. In 2009, EU passed proposed law to limit CO2 emission to accomplish 20% of renewable energy. The Japan government plans to expan achieve the green economies of scale up to 100 trillions in 2015. China has set the new target of cutting carbon dioxide emissions per unit of GDP by 40~45% by 2020 from the 2005 level. Taiwan government proposed “Energy Continuity Guidelines” for energy saving & CO2 emission suppression from 2016~2020 back to 2008 & from 2025 back to 2000. In 2010, China is the 2nd energy production & energy consumption country in the world. China is also the main consumer market in solar cell panels, wind-driven generators,…etc. The demands of Electric Vehicle, trolleybus and MW energy storage system lead the growth of Li-battery. We have better techniques of manufacture and talented persons in Taiwan, and obtain many experiences in manufacture from traditional industry to semi-conductor,LCD panel,…etc. We should apply to Li-battery industry to striving for superiority. The thesis focuses on study on key successful factors of lithium iron phosphate battery by literature review, interview, questionaire. The research method of the thesis applies AHP (Analytical Hierarchy Process) to analysis data required. They develope four item frame surfaces (expertise,cost,safety,marketing) and expect that “expertise” and “marketing” are more important than “cost” and “safety”. The thesis found, the three top selection criteria are “China marketing”, “Patent” and “Talent person”. We must foster talent and have to promote the qualities of product by applying our production experience such as standardization, automation ,…etc. In terms of R&D, we have to obtain achievements on technique and process, and expect to enhance competitive by proceeding the patent portfolio to prevent our technique be copy by competitors. Meanwhile, we have to expand China market to improve our profitability.
Lin, Hong-Yu, and 林鴻裕. "Research on State-of-Health of Lithium Iron Phosphate Batteries." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/61017328270530683055.
國立東華大學
電機工程學系
103
This thesis has put emphasis on the aging effect of lithium-iron (LiFePO4) batteries. The variations of such as capacity, internal parameters are analyzed. By intermittent discharging the batteries several times, the dynamic behavior of the terminal voltages are recorded. The battery behavior is modeled by an equivalent circuit, and the circuit parameters are derived by numerical methods such as curve-fitting and minimum square error. The experimental platform is equipped with the capability to control several influential factors, such as discharging current, ambient temperature, depth of discharge. The circuit parameter variation among the factors, and then summarize and sift out the parameters highly related to capacity aging. The obtained features are categorized as a training set for support vector machine to find several regression models which are capable of predicting the state-of-health of the aged batteries. The most accurate model is used to predict the state-of-health of the batteries not involved in the training procedure. The prediction results can reach a root square mean error as low as 3.3%.
Chang, Kai Chu, and 張凱筑. "The Study of Lithium Manganese(Iron) Phosphate Powders and Precursors." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/05537521557434157367.
Jen-Chieh, Yang, and 楊仁捷. "Preparation of lithium aluminium titanium phosphate electrolytes by sol-gel technique." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/25948499128542059360.
Chen, Yen Wei, and 陳彥瑋. "The study of lithium iron manganese-based phosphate powders and precursors." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/b8tgsb.
He, Chong-Ming, and 何崇銘. "The Study of Lithium Vanadium Phosphate Battery with Gel-Typed Electrolyte." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/75939173917239487513.
國立中興大學
物理學系所
102
The gel-typed electrolyte batteries, using Li3V2(PO4)3 as cathode and lithium metal as anode, were prepared. The specific capacity of the battery is improved by doping α-Al2O3 particles in polymer gel electrolyte. However, the specific capacities are only 83% and 42% of the theoretical value, when 1 C and 5 C charging-discharging rates are used, respectively. After charging-discharging 100 times using 1 C or 5C charging rate, the coulomb efficiencies are still 100%. This indicates the structural stable of Li3V2(PO4)3 during charging-discharging process.
You, Zhen-Hao, and 游鎮豪. "Equivalent Circuit Model and SOC Estimation for Lithium Iron Phosphate Batteries." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/37182703464700450083.
Ye, Shi-Guo, and 葉世國. "A Study on the Preparation of Lithium Metal Phosphate Cathode Materials." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/358skc.
國立臺北科技大學
化學工程研究所
97
Lithium ion batteries have been successfully utilized in various portable electronic devices. It is well known that the cathode materials have a significant influence on the electrochemical performance of the batteries. A among those cathode materials, LiMPO4 (M=Mn or Fe) has received much attention due to its large theoretical capacity, inexpensiveness, natural abundance, environmental neutrality, thermal stability in the fully charged state and good cycle stability. In this work, we use microwave to prepare LiMPO4 (M=Mn or Fe) powders because it has several characteristics, such as faster reaction rate, milder reaction conditions, higher chemical yield, lower energy consumption and better reaction selectivities. The precursors of LiMPO4 (M=Mn or Fe) were prepared by a sol-gel method using lithium hydroxide, ferrous sulfate, manganese sulfate, phosphoric acid and ethylene glycol as raw materials and the LiMPO4 (M=Mn or Fe)cathode materials was prepared in a microwave oven. The effect of microwave time and power an conversion was investigated. According to the experiments, we found that the microwave power 100W and the microwave time 60min and 90min could get the desired products. Finally, X-ray diffraction and scanning electron microscopy techniques were used to identify the crystalline phases and morphology of LiMPO4 (M=Mn or Fe).
Chen, Tse Hsi, and 陳昃熙. "Effects of lithium content and tape-casting processing conditions on the properties of lithium ion conducting membranes of lithium aluminum titanium phosphate and hybrid electrolyte lithium air batteries." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/ukjxy2.