Designing Lithium Argyrodite Solid‐State Electrolytes for High‐Performance All‐Solid‐State Lithium Batteries

Abstract All‐solid‐state lithium batteries (ASSLBs) with desirable advantages, such as high safety and energy density, simple packaging, and wide temperature tolerance, are considered promising energy storage devices to replace traditional lithium‐ion batteries with organic liquid electrolytes. Solid‐state electrolytes (SSEs) are the critical component in ASSLBs. Argyrodites, as a typical class of sulfide‐based lithium‐ion superconductors, represent the most promising SSEs with respect to their high ionic conductivity at room temperature, low cost, good compatibility towards Li metal, and extraordinary performance reported in ASSLBs. However, lithium argyrodites are inert gas‐protective, moisture‐sensitive, interface‐unstable, and working potential window‐limited, presenting the main challenges for their commercial use. In this review, we comprehensively summarized the basic physical and chemical properties, material synthesized strategies, chemical or electrochemical stabilities, and interface engineering of lithium argyrodite SSEs. Furthermore, the recent achievements and critical challenges for lithium argyrodite from the material level to battery applications are overviewed, and the future development opportunities of integrating the lithium argyrodite SSEs into ASSLBs have been prospected.