Effect of defects and defect distribution on Li-diffusion and elastic properties of anti-perovskite Li₃OCl solid electrolyte

In this work the effect of structural defects caused by doping and vacancies on the elastic properties and self-diffusion coefficient of Li ions in the Li₃OCl superionic conductor was investigated. In contrast to previous studies where high Li-ion diffusion in Li₃OCl was attributed to the Li-ion vacancies and interstitials, we found that both the type and distribution of defects in Li₃OCl significantly affected the diffusion coefficient, and the highest conductivity was obtained in a sample with a regular distribution of LiCl Schottky defects. Since the defect distribution will be determined by the experimental sample preparation, this provides a guide to improve the conductivity of Li₃OCl electrolyte. Moreover, the introduction of these defects only causes minor changes in the elastic properties of Li₃OCl solid electrolytes, which benefits the design of all-solid-state Li-ion batteries with high performance.