Sulfide-based solid electrolyte used for lithium ion secondary battery and production method for same, solid electrolyte layer, and lithium ion secondary battery

Abstract

A sulfide solid electrolyte to be used in a lithium-ion secondary battery, including an argyrodite crystal, in which the crystal is represented by a composition formula Lia-M-Zb-Hac; M is at least one element selected from Na, K, and elements each of which exists as any of divalent to pentavalent cations in the crystal; Z is at least one element selected from elements that exists as a divalent anion in the crystal; Z includes S; Ha is at least one element selected from the group consisting of F, Cl, Br, and I; a, b, and c in the composition formula indicate a ratio among contents (unit: at %) of the respective elements and satisfy 5<a<7, 4<b<6, and 0<c<2; and a maximum distance between Li ions in the crystal is 2.54 Å or shorter.

Dependencies are inferred from the claim text.