Sn-O dual-doped Li-argyrodite electrolytes with enhanced electrochemical performance

Abstract

Sn-O dual doping significantly improves the electrochemical properties of Li 6 PS 5 I solid electrolytes, including the ionic conductivity, the interfacial compatibility against Li metal, and Li dendrite suppression capability, and thereby enabling high performance Li-metal batteries. As a type of candidate for all-solid-state Li batteries, argyrodite solid electrolytes possess high ionic conductivity, but poor compatibility against Li metal. Here, we report novel Li 6 PS 5 I-based argyrodite sulfides with Sn-O dual doping, which is a powerful solution to comprehensively improve the performance of a material. The combination of O and Sn-aliovalent doping not only enables an improved ionic conductivity but more importantly realizes an intensively enhanced interfacial compatibility between argyrodite and Li metal and Li dendrite suppression capability. The assembled battery with Sn-O dual-doped electrolyte and Li anode demonstrates high capacity and decent cycling stability. Dual doping is thus believed to be an effective way to develop high performance sulfide solid electrolytes.