Preparation of (50-x)Li₂SO₄∙xLi₂WO₄∙50LiPO₃ (mol%) Glasses and Their Lithium-ion Conducting Properties

Abstract

With the aim of creating new lithium-ion conducting oxide glasses for all-solid-state lithium-ion batteries, we tried to prepare the glasses in the compositions (50-x)Li₂SO₄∙xLi₂WO₄∙50LiPO₃ (mol%) by use of a traditional melt-quenching method. The glass-transition temperatures of the obtained glasses were increased with an increase of the Li₂WO₄ contents. The bulk glasses showed relatively high lithium-ion conductivities in the range of 10^-6 to 10^-5 Scm^-1 at room temperature. On the other hand, the pellets, which were obtained by pressing the powdered glass samples, showed the conductivities in the range of 10^-7 to 10^-6 Scm^-1 at room temperature. The conductivities of the bulk glasses are about one order higher than those of the pellet samples. An all-solid-state battery was composed with the cathode composites of the cathode active materials LiNi_1/3Mn_1/3Co_1/3O₂ and the 25Li₂SO₄∙25Li₂WO₄∙50LiPO₃ (mol%) glass as solid electrolyte. The all-solid-state battery showed good charge-discharge performance at 100°C.