Sulfide solid electrolyte for all-solid secondary battery, method of preparing same, and all-solid secondary battery including the same

Abstract

A sulfide solid electrolyte for all-solid secondary batteries, a method of preparing the same, and an all-solid secondary battery, the sulfide solid electrolyte including lithium, phosphorus, sulfur, and a halogen, wherein: the sulfide solid electrolyte has an argyrodite-type crystal structure, a ratio (I(29.0)/I(30.0) ratio) of a peak intensity at a 2θ of 29±0.1° to a peak intensity at a 2θ of 30±0.1° is 0.06 or less, the peak intensities being obtained by X-ray diffraction analysis of the sulfide solid electrolyte, and a ratio (I(27.1)/I(30.0) ratio) of a peak intensity at a 2θ of 27.1±0.1° to a peak intensity at a 2θ of 30±0.1° is 0.06 or less, the peak intensities being obtained by X-ray diffraction analysis of the sulfide solid electrolyte.

Dependencies are inferred from the claim text.