Oxysulfide glass, Li3PO4-Li2S-SiS2, shows a high ionic conductivity of 1.4 x 10(3) S/cm at ambient temperature and a wide electrochemical window. It is chemically and electrochemically stable against lithium metal. LixCoO2 and In-Li-x were found to be good candidates for the electrode materials in solid state batteries with the glass for their electrode reactions with high reversibility. The solid state battery constructed with the materials reveals excellent cycling property, high rate capability up to almost 1 mA/cm(2), and extremely small residual current.