Добірка наукової літератури з теми "Li-Se Batteries"

Direct visualization of the dissolution and deposition reactions in Se cathodes resolves the competitive nucleation and growth behaviors dependent on the depletion of electrolyte-soluble polyselenides.

Garnet-type Li₇La₃Zr₂O₁₂ (LLZ) is regarded as a promising oxide-based solid electrolyte (SE) for solid-state lithium batteries (SSLBs) or other advanced Li-battery concepts like Li–air or Li–S batteries.

The use of chalcogenide elements, such as sulfur (S) and selenium (Se), as cathode materials in rechargeable lithium (Li) and sodium (Na) batteries has been extensively investigated. Similar to Li and Na systems, rechargeable potassium–sulfur (K–S) and potassium–selenium (K–Se) batteries have recently attracted substantial interest because of the abundance of K and low associated costs. However, K–S and K–Se battery technologies are in their infancy because K possesses overactive chemical properties compared to Li and Na and the electrochemical mechanisms of such batteries are not fully understood. This paper summarizes current research trends and challenges with regard to K–S and K–Se batteries and reviews the associated fundamental science, key technological developments, and scientific challenges to evaluate the potential use of these batteries and finally determine effective pathways for their practical development.

West Lafayette; Indiana University-Purdue University Indianapolis (IUPUI)
Lithium-ion batteries (LIBs) are commonly and widely applied in current numerous devices such as smart phones, laptops, electric vehicles and medical devices. The LIBs are considered as a mature technology in todays commercial market bene ted from their uncomplicated lithium intercalation and de-intercalation reactions, stable cycling performance and good working life as energy storage devices and power resources. However, the conventional LIBs with technical limits such as high weight, low lithium utilization and low speci c energy density hit the bottlenecks of further improvements and optimizations for meeting the growing power supply requirements. It is urgent to develop the second generations of rechargeable lithium batteries, which have the bene ts of low cost, high speci c capacity and high energy density with light weight. In this context, lithium-sulfur batteries (LSBs) and lithium-selenium (Li-Se) batteries attract much attention due to the high possibility to meet the requirements of high speci c capacity and high energy density. However, the technical challenges they are facing put some barriers before they can be successfully commercialized. By a brief summary, the challenges to be solved are current low energy density because of requiring large amount of liquid electrolyte, the highly ammability and unsafety of lithium metal, low active material content due to the necessary requirement of carbon and binder, and severe so-called shuttle effect resulting in low Coulombic effciency. Before solving these challenges, Li-S batteries or Li-Se batteries are unlikely to be successfully commercialized in our market. Therefore, numerous research is aimed at solving the challenges and further developing more advanced Li-S and Li-Se battery systems. In the present dissertation, the contributions are mainly focused on sulfur-based and selenium-based materials, which aim to solve the current existing challenges and improve the battery performance, herein obtain a higher potential for application. Four chapters are included in this dissertation, which aim to present the four studied projects. The rst research conducted in this dissertation is developing organo S/Se hybrid materials which require low E/S ratios of liquid electrolyte and show light shuttle effect, therefore indicate promising high energy density and cycling life. Secondly, the tin foil is used as lithium sources instead of metallic lithium anode, then incorporated with sulfur cathode as a full cell. The full cell design provides the potential using a metallic anode other than pure lithium and increase the safety factor of a battery system. In addition, nano-scale selenium/carbon nanotubes composite electrode is synthesized via a chemical reduction method. With the optimization on thickness of the composite electrodes, the Se cathode has an active material content of ~60% and shows stable long cycling life with maximizing the utilization of selenium. The nal research conducted in this dissertation is applying a macro molecule named cyanostar, which has the ability to chemically bind with polysul de species, thereupon to alleviate the shuttle effect in Li-S batteries. With the evidence from chemistry analysis and electrochemical comparison results presented in this dissertation, cyanostar is proven to have the potential for further applications in Li-S batteries.

In this thesis, we have attempted to understand the working principle of Li(Na)-S(Se) battery and following such understandings we have attempted towards the design of various S(Se)- cathode materials for the alkali based chalcogen batteries. In the final chapter, we have focussed on the development of anode materials for full Li-ion cell. The summary of the various chapters is as follows. Chapter 2 discusses about NaY-xS-PAni exhibiting remarkable electrochemical performance as a cost-effective sulfur cathode for rechargeable Li-S batteries. The superior electrochemical stability and performance of the NaY-xS-PAni is directly correlated to the novel NaY electrode structure in combination with the host polarity and ionic conductivity. The zeolite provides an optimum geometrical and chemical environment for precise confinement of the sulfur while the polyaniline coating provides electron conduction pathway along with extra polysulfide confinements. This cathode material exhibits very stable cycling for more than 200 cycles with relatively low specific capacity and modest rate capability. To develop a material for obtaining high specific capacity value we moved to carbon based host and the details are covered in chapter 3 and 4. To summarize Chapter 3, we have successfully extended the pressure induced capillary filling method for confinement of sulfur and selenium in the interior core of the MWCNTs. This method results in ultra-high loading yields of the chalcogens inside the MWCNTs. The ensuing composites S-CNT have been convincingly demonstrated as prospective cathodes in Li-S rechargeable batteries exhibiting very high specific capacities ~ 1000 mAh g-1 at C/10 current rates. The novelity of this host has been established by extending the work in encapsulating Se with the similar protocol and studying its electrochemical activity. The high efficiency of the Li-S/Se electrochemical reaction observed here is directly attributed to the efficacy of the encapsulation protocol of S/Se inside the CNTs. The polyselenides/polysulfides are completely confined within the precincts of the CNT cavity leading to an exceptionally stable battery performance at widely varying current densities. With the success of this encapsulation technique for the carbon based host, we developed another interconnected mesoporous microporous carbon host for sulfur encapsulation the details of which constitute the next chapter. In chapter 4, we have discussed here a novel S-cathode where the sulfur confining hierarchical carbon host synthesized using a sacrificial template can be very effectively employed for in Li-S rechargeable battery. The hierarchical mesoporous-microporous architecture comprising of both mesopores and micropores provide an optimal potential landscape which in turn traps high amounts of sulfur as well as polysulfides formed during successive charge-discharge cycles. The uniqueness of the carbon matrix translates to exceptionally stable reversible cycling and rate capability for Li. Such promising result with Li-S battery compelled us to check the performance with Na anode. This led to the development of intermediate temperature Na-S battery with JNC-S as the prospective cathode. It is envisaged that such materials design will be very promising in general for battery chemists especially for higher valent metal-sulfur systems (e.g. magnesium, aluminum). The host discussed here will be ideally suitable for introduction of dopants such as nitrogen, boron, thus enhancing it’s versatility as a heterodoped mesoporous-microporous host for varied applications. In all the preceding chapters, the focus was to encapsulate sulfur in some host structures. Chapter 5 deals with an alternative configuration for the Li-S battery that uses an oxide based interlayer to restrict the polysulfides. From the study discussed here, it can be concluded that NiOH-np/NiO-np can act as an efficient interlayer material for superior anode protection. The interlayer provides an anchor to hold back the polysulfides primarily on the cathode side by forming intermediates such as NiS3(OH) and NiS4(OH). Although, the specific capacity is less compared to the theoretically estimated value for S-cathode, the high cyclability coupled with extremely good rate capability performance makes this a very promising configuration of Li-S cell assembly for practical applications and deployment. The success of this strategy is expected to decrease the need for design of sophisticated S-scaffolds and lead to simpler Li-S rechargeable batteries. After an extensive discussion on development of cathodes for alkali based chalcogen batteries, we shifted gears and tried our hands in developing some eco-friendly anode materials. The details of graphitic carbonitride as an anode material for Li-ion cell has been discussed in chapter 6. To conclude, we have discussed here in detail the unique layered structure of the as-synthesized gCN and its impact on the intrinsic charge transport properties. Both factors eventually determine their electrochemical performance. The gCN discussed here is obtained using a very simple synthesis protocol in large yields from a very cheap organic precursor. The work highlights again the important role of chemical composition and structure on the functionality of the intercalation host. These have a strong bearing on the electronic charge distribution in the host and its eventual interaction with the intercalating ions. Compared to several non-trivial layered carbonaceous structures, the gCN interestingly displays 3-D ion transport. Additionally, it also sustains facile electron transport (2-D) despite the low concentration of carbon. In spite of the modest specific capacities as observed in case of the half cells, the gCN when assembled with (high) voltage cathodes in full Li-ion cells, the performance is quite encouraging. To the best of our knowledge this is for the first time that graphitic carbon nitrides have been demonstrated as an anode in full Li-ion cells. The potential of majority of the reported high surface area and high capacity complex carbonaceous structures in Li-ion cells are inconclusive. This is mainly due to the fact that the percentage of reports on full Li-ion cell performance is very rare. The full cell analysis of the gCN discussed here conclusively rules out the necessity of the requirement of high specific capacity materials in practical/commercial full cells. We envisage that the work discussed here will pave the way for synthesis of many such electrode materials from renewable resources resulting in the development of green and sustainable batteries. Overall we have been able to address some of the potential problems of Li-S and Li-ion battery systems. There is further scope of betterment with extensive study and this work opens the scope for it in future.

Les performances en cyclage des batteries Na-ion sont fortement associées à la qualité de l'interface électrode/électrolyte, où se produit la dégradation de l'électrolyte. Les récents avancements dans la connaissance de cette interface, de la composition de la couche de SEI, et des mécanismes de dégradation de l’électrolyte en solvant aprotiques sont décrits dans ce chapitre et comparé aux équivalents dans les batteries Li-ion.

In recent times the ship building and yacht industries have seen a surge in the requests for the application to the power generation, conversion and energy storage of technologies which were previously reserved to land-based uses or to niche sectors such as space, military, and scientific research. Such requests are often driven by seeking cleaner exhaust emissions, more efficient fuel consumption and higher passenger and crew comfort. Among these novel technologies we can mention fuel cells and (large) batteries based on Li-ion chemistries. These solutions are not only unconventional per se, they also carry along the necessity for advanced electrical system integration (even more so if combined in a hybrid architecture) or, for fuel cells, the need for the storage of dedicated fuels, e.g., liquid, or compressed hydrogen or methanol, and fuel treatment, e.g., evaporators and chemical reformers. The lack of prescriptive regulations covering such innovative solutions, both in terms of equipment and fuel, adds in challenge to their acceptance and certification from Regulatory Bodies and Flag Administrations. Furthermore, although high-level guidelines are provided, they often need to be tailored on a case-by-case basis and integrated with risk assessment exercises. The aim of this work is to give a comprehensive overview of the Classification tools available to date – be it prescriptive or risk-based – for the approval of novel designs and how do they relate to the existing statutory guidelines and to the established risk analysis instruments. The discussion will be corroborated by insights into some hands-on case studies in the yacht and cruise ship industry segments.

In this study, a multi-layer structure solid electrolyte (SE) for all-solid-state electrolyte lithium ion batteries (ASSLIBs) was fabricated and characterized. The SE was fabricated by laminating ceramic electrolyte Li1.3Al0.3Ti1.7(PO4)3 (LATP) with polymer (PEO)10-Li(N(CF3SO2)2 electrolyte and gel-polymer electrolyte of PVdF-HFP/ Li(N(CF3SO2)2. It is shown that the interfacial resistance is generated by poor contact at the interface of the solid electrolytes. The lamination protocol, material selection and fabrication method play a key role in the fabrication process of practical multi-layer SEs.