Cathodal Li-ion interfacial transport in sulfide-based all-solid-state batteries: Challenges and improvement strategies

Interface is a necessary channel of carrier permeation in sulfide-based all-solid-state lithium battery (ASSLB). Homogeneous and fast lithium-ion (Li⁺) interfacial transport of cathode is the overriding premise for high capability of ASSLBs. However, the inherent transport heterogeneity of crystalline materials in cathode and the cathode active material (CAM)/sulfide solid electrolyte (SSE) interfacial issues result in high interfacial impedance, decreasing the Li⁺ transfer kinetics. In this review, we outline the Li⁺ transport properties of CAMs and SSEs, followed by a discussion of their interfacial electro-chemo-mechanical issues. Commentary is also provided on the solutions to the multiple-scale interfacial Li⁺ transport failure. Furthermore, the underlying interdependent mechanisms between electrodes are summarized and overviewed. Finally, we suggest future paths to better comprehend and promote the interfacial Li⁺ transport in ASSLBs. This review provides an in-depth understanding of cathodal interfacial issues and the proposed improvement strategies will provide guidance for further advancement of high-performance ASSLBs.