Issues, Developments, and Computation Analyses of Interfacial Stability in All-Solid-State Li Batteries

Interfacial stability is one of the main issues in the development of all-solid-state batteries (ASSB), particularly for ceramics-based ASSB. The interfacial issues involve poor contacts between electrode and electrolyte materials, and interfacial instability upon cycling. The ceramics/metal and ceramics/ceramics contacts at the anode and cathode sides have problems of wetting and sintering, respectively. The chemical and electrochemical stability of electrolyte materials are other critical issues. Various approaches and techniques have been proposed to analyze and to solve the interfacial issues through either experimental or computational methods. Experimentally better contacts with enhanced stability are achieved by avoiding direct contacts between electrode and electrolyte particles, or by impeding the interfacial reactions kinetically. Computation has been used to provide supporting evidence for the experiments, including the electrochemical windows of electrolyte materials and interfacial reactions between electrodes and electrolytes. In addition, computation has been used for guiding materials design. This review paper summarizes the issues and current progress in interfacial stability analyses and modification of ASSB.