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Abstract With the increasing use of Li batteries for storage, their safety issues and energy densities are attracting considerable attention. Recently, replacing liquid organic electrolytes with solid‐state electrolytes (SSE) has been hailed as the key to developing safe and high‐energy‐density Li batteries. In particular, Li1+xAlxTi2−x(PO4)3(LATP) has been identified as a very attractive SSE for Li batteries due to its excellent electrochemical stability, low production costs, and good chemical compatibility. However, interfacial reactions with electrodes and poor thermal stability at high temperatures severely restrict the practical use of LATP in solid‐state batteries (SSB). Herein, a systematic review of recent advances in LATP for SSBs is provided. This review starts with a brief introduction to the development history of LATP and then summarizes its structure, ion transport mechanism, and synthesis methods. Challenges (e.g., intrinsic brittleness, interfacial resistance, and compatibility) and corresponding solutions (ionic substitution, additives, protective layers, composite electrolytes, etc.) that are critical for practical applications are then discussed. Last, an outlook on the future research direction of LATP‐based SSB is provided.
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Understanding Electrochemical Reaction Mechanisms of Sulfur in All‐Solid‐State Batteries through Operando and Theoretical Studies **
Abstract Due to its outstanding safety and high energy density, all‐solid‐state lithium‐sulfur batteries (ASLSBs) are considered as a potential future energy storage technology. The electrochemical reaction pathway in ASLSBs with inorganic solid‐state electrolytes is different from Li‐S batteries with liquid electrolytes, but the mechanism remains unclear. By combining operando Raman spectroscopy and ex situ X‐ray absorption spectroscopy, we investigated the reaction mechanism of sulfur (S8) in ASLSBs. Our results revealed that no Li2S8,Li2S6,and Li2S4were formed, yet Li2S2was detected. Furthermore, first‐principles structural calculations were employed to disclose the formation energy of solid state Li2Sn(1≤n≤8), in which Li2S2was a metastable phase, consistent with experimental observations. Meanwhile, partial S8and Li2S2remained at the full lithiation stage, suggesting incomplete reaction due to sluggish reaction kinetics in ASLSBs.
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- PAR ID:
- 10419123
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 62
- Issue:
- 20
- ISSN:
- 1433-7851
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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