Toward High Rate Performance Solid‐State Batteries

Abstract The increasing demand for safe lithium‐ion batteries with high energy density has pushed the development of all‐solid‐state batteries (ASSBs). With the development of promising solid electrolytes (SEs) such as Li₁₀GeP₂S₁₂ and Li₆PS₅Cl with high ionic conductivity in recent years, the bottleneck for high‐performance ASSBs is no longer sluggish Li⁺ diffusion caused by SEs. Furthermore, significant improvement in the cycle performance has been achieved by understanding electrochemomechanical properties, preventing undesirable side reactions between SEs and active materials, and employing advanced packaging technology. However, poor rate capability caused by several factors, including sluggish Li⁺ kinetics at the interface between active materials and SEs, poor interfacial contact between particles, thick SE layers, and Li dendrite growth, limits the practical applications, especially in electric vehicles. The high‐rate performance is of paramount importance in the current development of battery technology. In this review, the fundamental understanding of the parameters governing the rate capability in ASSBs is discussed and the distinctive features and research strategies toward high‐rate performance are highlighted. The discussion and perspectives about kinetic rate limitations and research strategies are expected to stimulate further progress in fast charging ASSBs.