Novel Amorphous Nitride‐Halide Solid Electrolytes with Enhanced Performance for All‐Solid‐State Batteries

Abstract

Solid electrolytes (SEs) in all-solid-state batteries (ASSBs) are garnering considerable attention for their potential applications in next-generation energy storage systems. Amorphous SEs with dual-anion hold great promise for achieving favorable performance, such as high ionic conductivity and good compatibility with electrodes within ASSBs. Here, we discover a family of amorphous nitride-halide SEs, Li_3xMCl_yN_x (M=Ta or La, 1≤3x≤1.4, y=5 or 3), which can achieve ionic conductivities up to 7.34 mS cm^-1 at 30 °C. The amorphous properties and local structures are investigated using powder X-ray diffraction, cryogenic transmission electron microscopy, and atomic pair distribution function analysis. Impressively, ASSBs employing amorphous Li_3xTaCl₅N_x have demonstrated good performance at high rates and charging voltages, as well as at low temperature.