Abstract: Provided are: a modified sulfide solid electrode containing a sulfide solid electrolyte having a BET specific surface area of 10 m2/g or more and containing a lithium atom, a sulfur atom, a phosphorus atom, and a halogen atom, and an epoxy compound, in which the modified sulfide solid electrolyte has a peak at 2800 to 3000 cm?1 in an infrared absorption spectrum obtained by FT-IR spectroscopy (ATR method); and a method for producing the modified sulfide solid electrolyte, which has excellent coating suitability when applied as a paste and is capable of efficiently exhibiting excellent battery performance even when a sulfide solid electrolyte having a large specific surface area is used.

Abstract: Provided are a method of manufacturing a modified sulfide solid electrolyte, which is excellent in coating suitability when applied as a paste even if a sulfide solid electrolyte has a large specific surface area, and can efficiently exhibit an excellent battery performance, the modified sulfide solid electrolyte obtained by the manufacturing method, and an electrode combined material and a lithium ion battery which exhibit an excellent battery performance. The method includes: mixing an organic halide and an organic solvent with a sulfide solid electrolyte having a BET specific surface area of 10 m2/g or more and containing a lithium atom, a sulfur atom, a phosphorus atom, and a halogen atom; and removing the organic solvent.