Electrical and electrochemical properties of the 70Li2S·(30 − x)P2S5·xP2O5 glass-ceramic electrolytes

The electrical and electrochemical properties of the 70Li2S·(30 − x)P2S5·xP2O5 glass-ceramics were investigated. The glass-ceramics with up to 5 mol% of P2O5 kept high conductivity over 10− 3 S cm− 1. The 70Li2S·27P2S5·3P2O5 glass-ceramic exhibited the highest conductivity of 3.0 × 10− 3 S cm− 1 at room temperature and the lowest activation energy of 16 kJ mol− 1 for conduction. Electrochemical stability of the glass-ceramic was improved by substituting 3 mol% of P2O5 for P2S5 because the oxygen-incorporated Li7P3S11 crystal would be precipitated in the glass-ceramic. The all-solid-state cell using the 70Li2S·27P2S5·3P2O5 oxysulfide glass-ceramic worked as a lithium secondary battery at room temperature.