SOLID α-LITHIUM ELECTROLYTE

[Problem] To provide a solid Li-P-S sulfide electrolyte material which combines excellent electrochemical stability with high lithium-ion electroconductivity, a process for producing the electrolyte material, and a lithium battery including the solid sulfide electrolyte material. [Solution] A solid sulfide electrolyte material characterized by comprising Li element, P element, and S element, having, in analysis by X-ray powder diffractometry using a Cu-Kα X-ray line having a wavelength of 1.5418 A, peaks at positions in terms of 2θ of 17.90±0.20o, 29.0±0.50o, and 29.75±0.25o, and having an I B /I A value less than 0.50 where I A is the diffraction intensity for the peak at a 2θ of 17.90±0.20 and I B is the diffraction intensity for the peak at a 2θ of 18.50±0.20.