SULFIDE SOLID ELECTROLYTE MATERIAL, POSITIVE ELECTRODE MATERIAL, AND BATTERY

A sulfide solid electrolyte material includes a sulfide phase containing a sulfide material and an oxide phase containing an oxide formed by oxidation of the sulfide material. The oxide phase is located on a surface of the sulfide phase. The sulfide solid electrolyte material satisfies conditions: 1.28≦x≦4.06 and x/y≧2.60, where x denotes the oxygen-to-sulfur elemental ratio measured by XPS depth profiling at the outermost surface of the oxide phase; and y denotes the oxygen-to-sulfur elemental ratio measured by XPS depth profiling at a position 32 nm, estimated from the SiOsputtering rate, away from the outermost surface of the oxide phase.