Lithium ion conductive oxysulfide, Li3PO4–Li3PS4

Ionic conductivity of Li3PS4 was enhanced by the two ways: quenching method and addition of Li3PO4. The quenching method froze its high-temperature phase partially down to room temperature and increased its ionic conductivity by three times. Addition of Li3PO4 resulted in the formation of a new metastable phase, the composition of which was considered to be around 0.25Li3PO4–0.75Li3PS4. Its conductivity at room temperature was 7.3 × 10− 5 S cm− 1, which was about 100 times higher than that of Li3PS4.