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Electrochemical energy storage is a cost-effective, sustainable method for storing and delivering energy gener- ated from renewable resources. Among electrochemical energy storage devices, the lithium-ion battery (LIB) has dominated due to its high energy and power density. The success of LIBs has generated increased interest in sodium-ion battery (NaB) technology amid concerns of the sustainability and cost of lithium resources. In recent years, numerous studies have shown that sodium-ion solid-state electrolytes (NaSEs) have considerable potential to enable new cell chemistries that can deliver superior electrochemical performance to liquid-electrolyte-based NaBs. However, their commercial implementation is hindered by slow ionic transport at ambient and chemical/ mechanical incompatibility at interfaces. In this review, various NaSEs are first characterized based on individual crystal structures and ionic conduction mechanisms. Subsequently, selected methods of modifying interfaces in sodium solid-state batteries (NaSSBs) are covered, including anode wetting, ionic liquid (IL) addition, and composite polymer electrolytes (CPEs). Finally, examples are provided of how these techniques improve cycle life and rate performance of different cathode materials including sulfur, oxide, hexacyanoferrate, and phosphate-type. A focus on interfacial modification and optimization is crucial for realizing next-generation batteries. Thus, the novel methods reviewed here could pave the way toward a NaSSB capable of with- standing the high current and cycle life demands of future applications.
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Ion Pair Integrated Organic‐Inorganic Hybrid Electrolyte Network for Solid‐State Lithium Ion Batteries
Abstract A class of organic‐inorganic hybrid electrolyte with ion pair integrated network (X‐POSS‐IL‐LiTFSI) has been prepared by crosslinking of oligomeric octasilsesquioxanes grafted with imidazolium‐based ionic liquids for solid state lithium ion battery applications. X‐POSS‐IL‐LiTFSI is thermally stable and highly amorphous, and shows high ionic conductivities and excellent electrochemical stability. With further immobilization of a small fraction of ionic liquid, the ionic conductivity of X‐POSS‐IL‐LiTFSI has been significantly improved, e. g. 1.4×10−4 S/cm at ambinet temperature, to the level required by the practical battery applications, while maintaining the demensional integity. The coin cells of lithium batteries with the plasticized X‐POSS‐IL‐LiTFSI electrolytes exhibit high specific capacities at both ambient and elevated temperatures.
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- Award ID(s):
- 1704173
- PAR ID:
- 10080410
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Energy Technology
- Volume:
- 6
- Issue:
- 12
- ISSN:
- 2194-4288
- Page Range / eLocation ID:
- p. 2319-2325
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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