NOVELTY - The separator consists of inorganic particles or their aggregate having unique spectrum or color pattern according to predetermined rule.    USE - Separator is used in electrochemical device (claimed) such as lithium (metal/ion/polymer) secondary battery, used as power source for portable telephones, camcorders, notebook computers, personal computers and electric vehicles.    ADVANTAGE - The separator can be identified easily.    DETAILED DESCRIPTION - The separator consists of inorganic particles or their aggregate having unique spectrum or color pattern according to predetermined rule. The inorganic particles are chosen from alumina, zinc oxide, zinc sulfide, silica, zirconia, tin oxide, ceria, magnesia, calcium oxide, yttrium oxide, titania, antimony oxide, barium titanate, strontium titanate, lead zirconium titanate, lead lanthanum zirconium titanate (Pb1-xLaxZr1-yTiyO3), iron oxide (Fe3O4,Fe2O3,Fe2O3+FeO), cobalt-nickel oxide-chromium-iron oxide, lead chromate, zinc chromate, barium chromate, cadmium sulfide, iron oxy hydroxide (FeO(OH)nH2O), titania-nickel oxide-antimony oxide, lead carbonitride, calcium lead oxide, aluminum-iron-tin-lead oxide-antimony oxide, vanadium-tin oxide, vanadium-zirconia, praseodymium-zirconium silicate, chromium antimonate, chromium tungstate-titania, zirconium sulfate coated cadmium sulfide, (cadmium zinc)sulfide, lead chromate-lead oxide, lead chromate-lead molybdate, lead sulfate, ferric oxide+manganese oxide+manganate, zinc oxide.(aluminum, chromium, iron)oxide, mercury sulfide, cadmium sulfide-cadmium selenide, cadmium sulfide-mercury sulfide, antimony sulfide-antimony oxide, cobalt phosphate Co3(PO4)2, Co3(PO4)2.4H2O, Co3(PO4)2.8H2O), sodium aluminum silicate-sodium sulfide, iron hexacyano ferrate (Fe4(Fe(CN6)3).nH2O, cobalt oxide-alumina (CoO-nAl2O3), cobalt oxide-tin oxide-magnesia (CoO-nSnO2-mMgO, where n is 1.5-3.5 and m is 2-6), cobalt oxide+silica+alumina+ferric oxide+nickel oxide+manganese oxide, (cobalt, zinc)oxide-alumina/silica, vanadium-zirconium silicate, chromium trioxide, chromium oxy hydroxide, copper acetate, copper oxide-arsenate (3CuO(AsO2)2), (cobalt, zinc)oxide-aluminum chromate, calcium oxide-chromium trioxide.silica, aluminum-chromium oxide ((Al,Cr)2O3), antimony-tin oxide, cobalt, nickel-zirconium silicate, manganese, phosphorus- alpha -alumina, zinc oxide.(Al,Cr)2O3, chromium-calcium oxide.tin oxide.silica, iron-zirconium silicate, chromium, cobalt-calcium oxide.tin oxide.silica, zirconium silicate coated cadmium sulfide/selenide, zinc sulfide, zinc silicate, zinc-cadmium sulfide, calcium sulfide, strontium sulfide, calcium tungstate, silicon carbide or silicon nitride. The inorganic particles further comprise polymers capable of interconnecting and fixing the inorganic particles. The polymer is chosen from polyvinylidene fluoride-co-hexafluoropropylene, polyvinylidene fluoride-co-trichloroethylene, polymethylmethacrylate, polyacrylonitrile, polyvinylpyrrolidone, polyvinyl acetate, polyethylene-co-vinyl acetate, polyethylene oxide, cellulose acetate, cellulose acetate, butyrate, cellulose acetate, propionate, cyanoethyl pullulan, cyanoethyl polyvinyl alcohol, cyanoethyl cellulose, cyanoethyl sucrose, pullulan, carboxyl methyl cellulose, acrylonitrile-styrene-butadiene copolymer and polyimide. The separator consists of inorganic particles-containing layer provided on surface of porous substrate or porous portion of substrate. The porous substrate is chosen from high density polyethylene, low density polyethylene, linear low density polyethylene, ultrahigh molecular weight polyethylene, polypropylene, polyethylene terephthalate, polybutylene terephthalate, polyester, polyacetal, polyamide, polycarbonate, polyamide, polyether ether ketone, polyethersulfone, polyphenylene oxide, polyphenylene sulfide and polyethylene naphthalene. INDEPENDENT CLAIMS are included for the following:    (1) manufacture of the separator; and    (2) method of identifying a separator or electrochemical device.