Insight into Inorganic Solid‐State Electrolytes: Ionic Transport and Failure Mechanisms

Abstract All‐solid‐state lithium‐ion batteries (ASSLBs) with inorganic solid‐state electrolytes (ISEs) have great potential for enhanced safety, high energy density, and long lifetime. Numerous works have focused on designing high‐conductive materials and (electro)chemically stable interfaces, contributing to the rapid development of ASSLBs. However, the lack of a comprehensive and in‐depth understanding of the intrinsic ionic conduction and failure mechanisms of ISEs in ASSLBs limits their further improvement. In this work, the analysis of the ionic transport mechanisms is focused in the different crystalline states of ISEs including bulk crystal, grain boundary, and amorphousness. Various failure mechanisms of ISEs concerning structure degradation, mechanical pulverization, and lithium dendrite penetration that trigger the capacity attenuation of cells are also discussed. This work is wraped up by providing the perspective on how to optimize the electrochemical performance of ASSLBs, which can, with the hope, pave the way for achieving the commercialization of ASSLBs.