A method for producing a solid electrolyte, comprising: grinding raw materials comprising lithium sulfide and phosphorus sulfide in a hydrocarbon solvent, optionally comprising stirring a slurry comprising the raw materials and the hydrocarbon solvent in a reaction vessel, and optionally, circulating the slurry through a connecting pipe, wherein the method is carried out in an apparatus comprising the grinder, the reaction vessel and the connecting pipe that connects the grinder and the reaction vessel.

The present invention provides for synthesizing high optical quality multicomponent chalcogenide glasses without refractive index perturbations due to striae, phase separation or crystal formation using a two-zone furnace and multiple fining steps. The top and bottom zones are initially heated to the same temperature, and then a temperature gradient is created between the top zone and the bottom zone. The fining and cooling phase is divided into multiple steps with multiple temperature holds.

Provided is a solid electrolyte having a high ion conductivity and excellent in battery performance not going through a step of removing water such as a drying step, while simplifying the production process and reducing the production cost. Specifically, provided is a method for producing a sulfide-based solid electrolyte, including causing a reaction of an alkali metal sulfide and a specific substance in a solvent.

Provided is a solid electrolyte having a high ion conductivity and excellent in battery performance not going through a step of removing water such as a drying step, while simplifying the production process and reducing the production cost. Specifically, provided is a method for producing a sulfide-based solid electrolyte, including causing a reaction of an alkali metal sulfide and a specific substance in a solvent.

The present disclosure provides a method for producing a sulfide solid electrolyte having good ionic conductivity and water resistance. The method for producing a sulfide solid electrolyte includes: an amorphizing step of obtaining a sulfide glass by amorphizing a first raw material composition including Li.sub.2S, Li.sub.2CO.sub.3, P.sub.2S.sub.5, LiI and LiBr, and a heating step of heating the sulfide glass at a temperature equal to or higher than a crystallization temperature.

A method for producing a solid electrolyte, including: stirring a slurry including lithium sulfide and phosphorus sulfide in a hydrocarbon solvent in a reaction vessel, and circulating the slurry through a connecting pipe by a pump. The method is carried out in an apparatus including the reaction vessel and the connecting pipe connected to the pump and the reaction vessel.

A sulfide solid electrolyte material having a high Li ion conductivity is provided. A sulfide solid electrolyte material includes Li, P, I and S, having peaks at 2θ=20.2° and 23.6°, not having peaks at 2θ=21.0° and 28.0° in an X-ray diffraction measurement using a CuKα ray, and having a half width of the peak at 2θ=20.2° of 0.51° or less.

An additive manufacturing ink composition may include a fluid medium. The ink may further include a chalcogenide glass suspended within the fluid medium to form a chalcogenide glass mixture. The ink may also include a surfactant. A method for forming an additive manufacturing ink may include wet milling a chalcogenide glass in a fluid medium and a surfactant to produce a chalcogenide glass mixture. The method may also include, after wet milling the chalcogenide glass, processing the chalcogenide glass mixture to reduce an average particle size of the chalcogenide glass.

A device formation method may include printing a chalcogenide glass ink onto a surface to form a chalcogenide glass layer, where the chalcogenide glass ink comprises chalcogenide glass and a fluid medium. The method may further include sintering the chalcogenide glass layer at a first temperature for a first duration. The method may also include annealing the chalcogenide glass layer at a second temperature for a second duration. A device may include a substrate and a printed chalcogenide glass layer on the substrate, where the printed chalcogenide glass layer includes annealed chalcogenide glass, and where the printed chalcogenide glass layer is free from cracks.

A standalone lithium ion-conductive solid electrolyte including a freestanding inorganic vitreous sheet of sulfide-based lithium ion conducting glass is capable of high performance in a lithium metal battery by providing a high degree of lithium ion conductivity while being highly resistant to the initiation and/or propagation of lithium dendrites. Such an electrolyte is also itself manufacturable, and readily adaptable for battery cell and cell component manufacture, in a cost-effective, scalable manner.