Abstract: A method of preparing a sulfide-based solid electrolyte according to embodiments comprises mixing a solvent and precursors in a reactor. In the reactor, an open vacuum atmosphere is formed. While maintaining the open vacuum atmosphere in the reactor, a mixture inside the reactor may undergo a reaction under conditions of stirring or applying ultrasonic waves. Accordingly, a high-purity sulfide-based solid electrolyte may be prepared with high efficiency.

Abstract: One embodiment of the present disclosure includes a method of producing high-purity alkali metal sulfide including mixing an alkali metal sulfide salt precursor and a reducing agent to form a mixture, reducing the mixture to obtain alkali metal sulfide; and purifying the obtained alkali metal sulfide.

Abstract: A method of preparing a sulfide-based solid electrolyte according to embodiments comprises mixing a solvent and a precursor in a reactor. An open vacuum atmosphere may be formed within the reactor. The mixture inside the reactor may be caused to react by stirring or under conditions of applying ultrasonic waves while maintaining the open vacuum atmosphere within the reactor. Accordingly, a high-purity sulfide-based solid electrolyte may be prepared with high efficiency.

Abstract: Provided are a method for preparing a sulfide-based solid electrolyte, a sulfide-based solid electrolyte prepared by the method, and an all-solid-state lithium secondary battery including the sulfide-based solid electrolyte. The method includes a) mixing Li2S with P2S5 to prepare a mixed powder, b) placing the mixed powder, an ether, and stirring balls in a container, sealing the container, followed by stirring to prepare a suspension, and c) stirring the suspension under high-temperature and high-pressure conditions to prepare sulfide-based solid particles.

Abstract: The present invention relates to a method for preparing a sulfide-based solid electrolyte, a sulfide-based solid electrolyte prepared by the method, and an all-solid-state lithium secondary battery including the sulfide-based solid electrolyte. The method of the present invention includes a) mixing Li2S with P2S5 to prepare a mixed powder, b) placing the mixed powder, an ether, and stirring balls in a container, sealing the container, followed by stirring to prepare a suspension, and c) stirring the suspension under high-temperature and high-pressure conditions to prepare sulfide-based solid particles.

Abstract: A method of manufacturing an argyrodite-type solid electrolyte, an argyrodite-type solid electrolyte, and an all-solid-state battery including the argyrodite-type solid electrolyte are provided. The method includes a first step of adding precursors represented by the following Formulas 1 and 2 into a polar aprotic solvent, followed by stirring to obtain a reaction solution; a second step of adding P2S5 into the stirred reaction solution, followed by further stirring to form a precipitate obtained as a result of the reaction in the reaction solution; and a third step of drying and heat-treating the reaction solution in which the precipitate is formed to obtain a solid electrolyte: [Formula 1] A2S [Formula 2] AX wherein A represents an alkali metal, and X represents an element of the halogen group.