Evaluation of elastic modulus of Li₂S–P₂S₅ glassy solid electrolyte by ultrasonic sound velocity measurement and compression test

Abstract

Elastic modulus is an important factor of solid electrolytes for an all-solid-state battery as a next-generation battery. In this study, Young’s moduli of dense pellets of the Li₂S–P₂S₅ glass solid electrolytes prepared by room temperature pressing and hot pressing were investigated. The Young’s moduli of Li₂S–P₂S₅ hot-pressed pellets measured by ultrasonic sound velocity measurements were 18–25 GPa and those of cold-pressed pellets were about 14–17 GPa. The compression test was also done to determine Young’s modulus. The Young’s modulus of Li₂S–P₂S₅ glasses increased with increasing the Li₂S content in both hot press and cold press pellets. The Young’s moduli were lower than those of oxide based solid electrolytes.