Abstract: A sulfide solid electrolyte includes: a crystal phase and an anion, in which the phase includes an argyrodite crystal including Li, P, S, and Ha, the Ha is at least one element selected from F, Cl, Br, and I, the anion includes an oxide anion having a P—O bond, at least a part of the oxide anion is different from an anion constituting the argyrodite crystal and constitutes a polyanionic structure, when an entire composition of the electrolyte is LiaMSbHacOx, certain relationships are satisfied, the M is at least one element selected from a metal element and a metalloid element in groups 2 to 15 of a periodic table, the at least one element including P, and 60% or more of a total content of O is bonded to the M.

Abstract: The present invention relates to a method for manufacturing a sulfide solid electrolyte powder, the method including, in this order: obtaining a sulfide solid electrolyte containing at least one of a crystal phase and an amorphous phase which contain Li, P, and S; pulverizing the sulfide solid electrolyte to obtain a powder; and heating and drying the powder in an atmosphere with a dew point of ?60° C. to ?40° C., in which the pulverization is performed by using a non-aqueous organic solvent, and when a concentration of moisture contained in the non-aqueous organic solvent in the pulverization is x (ppm), and a moisture concentration in a heating space in the heating and drying is y (g/m3), y<0.00085x+0.056, and 30<x?170 are satisfied.

Abstract: The present invention relates to a sulfide solid electrolyte to be used for a lithium-ion secondary battery, the sulfide solid electrolyte including: an argyrodite crystal including Li, P, S, and Ha, in which the Ha represents at least one element selected from the group consisting of F, Cl, Br, and I, and the Ha includes at least one of Cl and Br, the argyrodite crystal satisfies at least one of requirements (A) and (B), and in the argyrodite crystal, relationships of {(1/?(S))×[S2?]+(1/?(O))×[O2?]+(1/?(Br))×[Br?]+(1/?(Cl))×[Cl?]+(1/?(F))×[F?]}?0.36 and [S2?]+[O2?]+[Br?]+[Cl?]+[F?]=1 are satisfied.

Abstract: The present invention relates to a sulfide solid electrolyte to be used for a lithium-ion secondary battery. The sulfide solid electrolyte contains: an argyrodite crystal containing Li, P, S, and Ha (F, Cl, Br, and I). Relationships of {(1/?(S))×[S2-]0+(1/?(O))×[O2-]0+(1/?(Br))×[Br?]0+(1/?(Cl))×[Cl?]0+(1/?(F))×[F?]0}?0.33 and [S2-]0+[O2-]0+[Br?]0+[Cl?]0+[F?]0=1 are satisfied, where [S2-]0, [O2-]0, [Br?]0, [Cl?]0, and [F?]0 are surface anion contents, and ? is an electronegativity thereof.