The importance of A-site cation chemistry in superionic halide solid electrolytes.

Halide solid electrolytes do not currently display ionic conductivities suitable for high-power all-solid-state batteries. We explore the model system AZrCl (A = Li, Na, Cu, Ag) to understand the fundamental role that A-site chemistry plays on fast ion transport. Having synthesised the previously unknown AgZrCl we reveal high room temperature ionic conductivities in CuZrCl and AgZrCl of 1 × 10 and 4 × 10 S cm, respectively.