New Lithium-Ion Conducting Crystal Obtained by Crystallization of the Li[sub 2]S–P[sub 2]S[sub 5] Glasses

A lithium-ion highly conductive new crystal was first precipitated in the glass-ceramics obtained by crystal- lization of the glasses. The glass-ceramic heated at showed the highest conductivity of at room temperature and the lowest activation energy of for conduction. The new crystal was formed by heat-treatment from , and the crystal was present at , indicating that the new crystal was precipitated as a metastable phase. The superionic metastable phase is responsible for the high conductivity and low activation energy of the glass-ceramics.