Affiliation:
1. Department of Mechanical and Materials Engineering University of Western Ontario 1151 Richmond St London Ontario N6A 3K7 Canada
Abstract
AbstractInsertion‐type compounds based on oxides and sulfides have been widely identified and well‐studied as cathode materials in lithium‐ion batteries. However, halides have rarely been used due to their high solubility in organic liquid electrolytes. Here, we reveal the insertion electrochemistry of VX3 (X=Cl, Br, I) by introducing a compatible halide solid‐state electrolyte with a wide electrochemical stability window. X‐ray absorption near‐edge structure analyses reveal a two‐step lithiation process and the structural transition of typical VCl3. Fast Li+ insertion/extraction in the layered VX3 active materials and favorable interface guaranteed by the compatible electrode‐electrolyte design enables high rate capability and stable operation of all‐solid‐state Li‐VX3 batteries. The findings from this study will contribute to developing intercalation insertion electrochemistry of halide materials and exploring novel electrode materials in viable energy storage systems.