▎ 摘　　要

NOVELTY - A sulfide-based solid electrolyte is lithium-sulfur-phosphorus-lithium halide-type sulfide solid electrolyte systems doped with metals or metalloids. USE - Sulfide-based solid electrolyte used for positive electrode composite of all-solid-state battery (all claimed) e.g. lithium-ion battery. Uses include but are not limited to cell phones, laptops, video cameras, medical devices, electric and hybrid electric vehicles, etc. ADVANTAGE - The electrolyte has high ionic conductivity, stability with respect to a lithium metal negative electrode, and excellent electrochemical cycle characteristics by doping the metal into a compound containing lithium, phosphorus, sulfur and halogen elements. DETAILED DESCRIPTION - A sulfide-based solid electrolyte is lithium-sulfur-phosphorus-lithium halide (Li2S-P2S5-LiX or Li2S-P2S5-LiX-LiX', where X and X' are different elements chosen from fluorine, chlorine, bromine or iodine, X is preferably iodine and X' is preferably bromine) type sulfide solid electrolyte systems doped with metals or metalloids. INDEPENDENT CLAIMS are included for the following: preparation of the sulfide-based solid electrolyte, which involves performing amorphization by obtaining an amorphized solid electrolyte powder by mixing and pulverizing a doping material containing lithium sulfide, phosphorus pentasulfide, lithium-halide (Li-X) and a transition metal or metalloid, and heat-treating the amorphized solid electrolyte; an all-solid-state battery, which comprises the electrolyte, positive electrode and negative electrode; and a positive electrode composite, which comprises a conductive material comprising activated carbon, graphene oxide, carbon nanotubes, and/or carbon black, cathode material (M) comprising lithium sulfide, sulfur, lithium-manganese-oxide (LiMn2O4), lithium-nickel-cobalt-manganese oxide (LiNi0.8Co0.1Mn0.1O2), lithium-nickel-cobalt-manganese oxide (LiNi0.6Co 0.2Mn0.2O2), lithium-cobalt dioxide, lithium-iron phosphate (LiFePO4), lithium-nickel-manganese oxide (LiNi0.5Mn1.5O4) and/or lithium-nickel-cobalt-aluminum oxide, and the electrolyte.