Provided is a production method for a sulfide solid electrolyte capable of preventing generation of a hydrogen sulfide gas even when brought into contact with moisture while capable of preventing reduction in ionic conductivity, the method includes mixing a raw material inclusion containing at least two raw materials, the raw material inclusion contains at least one selected from a lithium atom, a sulfur atom, a phosphorus atom and a halogen atom, and the raw material inclusion contains modified P.sub.2S.sub.5. Also provided are the sulfide solid electrolyte produced by the method, an electrode mixture, a lithium ion battery, and a modified P.sub.2S.sub.5 for production of a sulfide solid electrolyte.

A positive electrode active material includes a conductive base material and an active substance distributed at the conductive base material. The active substance has a core-shell structure including a core layer material and a shell layer material. The conductive base material includes a carbon material, the core layer material includes a phosphate-based sodium salt material, and the shell layer material includes a metal oxide.

A method for forming a sintered composition includes providing a slurry precursor including a chalcogenide compound; tape casting the slurry precursor to form a green tape; and sintering the green tape at a temperature in a range of 500° C. to 1350° C. for a time in a range of less than 60 min. An energy device includes a first sintered, non-polished electrode having a first surface and a second surface; a first current collector disposed on the first surface of the first electrode; an electrolyte layer disposed on the second surface of the first electrode; and a second electrode disposed on the electrolyte layer.

A method for forming a sintered composition includes providing a slurry precursor including a chalcogenide compound; tape casting the slurry precursor to form a green tape; and sintering the green tape at a temperature in a range of 500° C. to 1350° C. for a time in a range of less than 60 min. An energy device includes a first sintered, non-polished electrode having a first surface and a second surface; a first current collector disposed on the first surface of the first electrode; an electrolyte layer disposed on the second surface of the first electrode; and a second electrode disposed on the electrolyte layer.

A method for activating two-dimensional host materials for a multivalent/polyatomic ion battery may include adding a pillaring salt in electrolyte. This process may be followed by in-situ electrochemically intercalating the pillaring ions, solvent molecules and multivalent ions into the van der Waals gap of host materials. After the activation process, the host material is transformed into an interlayer-expanded 2D material with significantly enhanced specific capacity and rate performance for multivalent ion intercalation.

A method for activating two-dimensional host materials for a multivalent/polyatomic ion battery may include adding a pillaring salt in electrolyte. This process may be followed by in-situ electrochemically intercalating the pillaring ions, solvent molecules and multivalent ions into the van der Waals gap of host materials. After the activation process, the host material is transformed into an interlayer-expanded 2D material with significantly enhanced specific capacity and rate performance for multivalent ion intercalation.

An active material contains: a compound containing lithium (Li) element, sulfur (S) element, and an element M and containing a crystalline phase having an argyrodite-type crystal structure; and a conductive material dispersed on the surface or in the interior of particles of the compound. The element M represents phosphorus (P) element or the like. The active material is a composite material of the compound and the conductive material. It is preferable that the conductive material is a carbon material or a metallic material. It is also preferable that the content of the lithium element in the active material is from 10 to 25% by mass.

The present invention relates to a liquid composition for forming an electrochemical device contains one or both of an active material or an electrolyte; a dispersion medium; and a polymer, wherein the polymer contains constituent units having one or both of an amide bond or an imide bond, and having a group represented by a following general formula (I): ##STR00001##
wherein X is an oxygen atom, or a carbon atom substituted with a hydrogen atom or an alkyl group, wherein R.sup.1, R.sup.2, R.sup.3, and R.sup.4 are each independently hydrogen atoms, substituted or unsubstituted alkyl groups, or substituted or unsubstituted cycloalkyl groups, and m and n are positive integers.

The present invention relates to a liquid composition for forming an electrochemical device contains one or both of an active material or an electrolyte; a dispersion medium; and a polymer, wherein the polymer contains constituent units having one or both of an amide bond or an imide bond, and having a group represented by a following general formula (I): ##STR00001##
wherein X is an oxygen atom, or a carbon atom substituted with a hydrogen atom or an alkyl group, wherein R.sup.1, R.sup.2, R.sup.3, and R.sup.4 are each independently hydrogen atoms, substituted or unsubstituted alkyl groups, or substituted or unsubstituted cycloalkyl groups, and m and n are positive integers.

A composition for forming an active material layer, including a sulfide-based solid electrolyte, an active material, a conductive auxiliary agent including a carbonaceous material, and a dispersion medium, in which the dispersion medium includes at least one ketone compound dispersion medium in which two aliphatic groups each having 4 or more carbon atoms are bonded to a carbonyl group; a method for manufacturing the composition for forming an active material layer; a method for manufacturing a solid electrolyte-containing sheet; and a method for manufacturing an all-solid state secondary battery.