Halide-type Li-ion conductors: Future options for high-voltage all-solid-state batteries

The design of high-energy-density batteries is the future goal of research on Li-ion batteries. Halide-type solid-state electrolytes (SSEs) exceed their counterparts in terms of their stability at high potential. In this minireview, we discuss the developments in the work on halide-type SSEs for all-solid-state Li batteries. In particular, we focus on the Li₃InCl₆ structure. The effect of synthesis routes on this structure, as well as the convertible products resulting from its phase changes, is discussed. Conductivity can be increased and the electrochemical window can be improved through doping with different materials. Our review aims to provide readers with an overview of the stability and degradation of Li₃InCl₆ SSE and the structure of halide-type SSEs (Li–M–X, where M is a metal and X is a halogen).