Sodium-Ion Conducting Solid Electrolytes in the Na2S–In2S3 System

Abstract

The development of solid electrolytes is necessary for practical applications of all-solid-state Na-ion batteries. In this study, we systematically developed sulfide Na-ion conductors with central In cations, prepared by solid-state reaction and mechanochemical methods. Thermodynamically stable crystals of Na5InS4 and NaInS2 were obtained by the solid-state reaction method, whereas amorphous and/or metastable phases were produced by the mechanochemical method. Two new metastable phases, Na5InS4 and NaInS2, are expected to be examined in the future as end-members of sulfide Na-ion conductors with central In cations.

Keywords

• solid electrolyte
• na ion conductor
• sulfide electrolyte
• all-solid-state na battery