The invention provides a
sulfide electrolyte, a preparation method thereof and a
solid-state battery, and the preparation method comprises the following steps: a) providing a
raw material containing Li, S, M and X, the D50 particle size of the
raw material being 1-10 [mu] m, and the surface adsorbed
water content of the
raw material being less than or equal to 100 ppm; and b)
sintering the raw material containing Li, S, M and X, and crushing to obtain the Argyrolite type
sulfide electrolyte. The raw materials containing Li, S, M and X with the D50 particle size being 1-10 microns and the surface adsorbed
water content being smaller than or equal to 100 ppm are adopted for
sintering to prepare the Argyrolite type
sulfide electrolyte, the contact area between the raw materials can be increased, the reaction
activation energy can be reduced, the
solid-
solid reaction rate can be increased, meanwhile, side reactions are prevented, the pure-phase Argyrolite type sulfide electrolyte is obtained, and the
ionic conductivity of the electrolyte is improved.