Electrical and electrochemical properties of glass–ceramic electrolytes in the systems Li2S–P2S5–P2S3 and Li2S–P2S5–P2O5

Electrical and electrochemical properties of the 70Li2S·(30 − x)P2S5·xP2S3 and the 70Li2S·(30 − x)P2S5·xP2O5 (mol%) glass–ceramics prepared by the mechanical milling technique were investigated. Glass–ceramics with 1 mol% P2S3 and 3 mol% P2O5 showed the highest conductivity of 5.4 × 10− 3 S cm− 1 and 4.6 × 10− 3 S cm− 1, respectively. Moreover, these glass–ceramics showed higher electrochemical stability than the 70Li2S·30P2S5 (mol%) glass–ceramic. From the XRD patterns of the obtained glass–ceramics, trivalent phosphorus and oxygen were incorporated into the Li7P3S11 crystal. We therefore presume that the Li7P3S11 analogous crystals, which were formed by incorporating trivalent phosphorus and oxygen into the Li7P3S11 crystal, improve the electrical and electrochemical properties of the glass–ceramics. An all-solid-state cell using the 70Li2S·29P2S5·1P2S3 (mol%) glass–ceramic as solid electrolyte operated under the high current density of 12.7 mA cm− 2 at the high temperature of 100 °C. The cell showed an excellent cyclability of over 700 cycles without capacity loss.