Abstract: A quaternary ammonium salt of the formula (1), electrolytic solution and electrochemical device using the salt wherein R1 is straight-chain or branched alkyl having 1 to 4 carbon atoms, R2 is straight-chain or branched alkyl having 1 to 3 carbon atoms, and X? is N(CN)2?, SCN?, NO3?, NCO? or NO2?.

Abstract: Disclosed is a non-aqueous electrolyte comprising: a first acrylate compound having one or two acryl groups; a second acrylate compound having three or more acryl groups; an electrolyte salt; and an organic solvent. Also, disclosed is an electrode comprising a coating layer formed partially or totally on a surface thereof, the coating layer comprising: (i) a reduced form of a first acrylate compound having one or two acryl groups; and (ii) a reduced form of a second acrylate compound having three or more acryl groups. Further, disclosed in an electrochemical device comprising a cathode, an anode, a separator and a non-aqueous electrolyte, wherein (i) the non-aqueous electrolyte is the above non-aqueous electrolyte; and/or (ii) the cathode and/or the anode is the above electrode.

Abstract: Charge-discharge cycle performance is improved in a lithium secondary battery including a negative electrode containing a negative electrode active material having silicon as its main component, provided on a surface of a current collector, a positive electrode containing a positive electrode active material, and a non-aqueous electrolyte. The positive electrode active material is a lithium transition metal oxide containing Li and Co and having a layered structure, and further containing a group IVA element of the periodic table, such as Zr, Ti, or Tf, and a group IIA element of the periodic table, such as Mg.

Abstract: There is provided a battery including a positive electrode that includes an active material layer formed on a positive electrode current collector; a negative electrode that includes active material layers formed on first and second principal planes of a negative electrode current collector and the active material layer on the second principal plane has an alloyed region smaller than an alloyed region the active material layer has on the first principal plane between the second principal plane and the current collector; and an electrolyte.

Abstract: A non-aqueous electrolyte secondary battery including: a positive electrode that contains a transition metal oxide capable of absorbing and desorbing lithium ions; a negative electrode that is capable of absorbing and desorbing lithium ions; a porous film that is interposed between the positive electrode and the negative electrode; and a non-aqueous electrolyte, wherein at least one selected from inorganic oxide and polyamide is contained in the porous film, and 5 to 15 vol % of ethylene carbonate is contained in a non-aqueous solvent that is contained in the non-aqueous electrolyte.

Abstract: A rolled foil of surface roughened copper as thick as 26 ?m for example having a surface formed into an irregular shape with copper precipitated thereon by an electrolytic method is prepared as a negative electrode collector. Tin (Sn) or germanium (Ge) is deposited on the rolled foil described above, so that a negative electrode active material layer is formed. Note that the deposited tin or germanium is amorphous. The arithmetic mean roughness Ra in the surface-roughened rolled foil described above is preferably not less than 0.1 ?m nor more than 10 ?m. A non-aqueous electrolyte is produced by adding sodium hexafluorophosphate as an electrolyte salt in a concentration of 1 mol/l to a non-aqueous solvent produced by mixing ethylene carbonate and diethyl carbonate in the ratio of 50:50 by volume.

Abstract: An electrolyte capable of improving battery characteristics even at high temperatures, a battery including the electrolyte, and a method for manufacturing an electrolyte are provided. The electrolyte contains at least one type of compound represented by the following formula: where R1, R2, R3, and R4 independently represent a hydrogen group, a fluorine group, a methyl group, an ethyl group, or a group in which a fluorine group has substituted for a part of the methyl group or the ethyl group; at least one of R1, R2, R3, and R4 is a group containing fluorine (F); and X, Y, and Z independently represents sulfur (S) or oxygen (O) except the case in which all of X, Y, and Z are oxygen (O), that is, X=Y=Z=O.

Abstract: In a nonaqueous electrolyte secondary battery having a positive electrode containing a positive electrode active material, a negative electrode containing a negative electrode active material, and a nonaqueous electrolyte, as the positive electrode active material or as the negative electrode active material, a mixture containing molybdenum dioxide and lithium titanate in a weight ratio (molybdenum dioxide:lithium titanate) of 90:10 to 50:50 is used.

Abstract: Disclosed is a lithium battery including a silicon negative electrode, a lithium mixed metal oxide positive electrode, a separator disposed between the negative and positive electrodes to define a reservoir region, an electrolytic solution filled in the reservoir region, and a sealant structure wrapped around the silicon negative electrode, the lithium mixed metal oxide positive electrode, the separator, and the electrolytic solution. The electrolytic solution includes an organic solvent, a lithium salt, and an additive. The additive includes a maleimide compound and vinylene carbonate. The silicon negative electrode of the lithium battery employing the described electrolytic solution has higher cycle efficiency and longer operating lifespan.

Abstract: There is provided a method for producing an electrolyte solution for lithium ion batteries, in which lithium hexafluorophosphate is used as an electrolyte, comprising the steps of (a) reacting phosphorus trichloride, chlorine and lithium chloride in a nonaqueous organic solvent; and (b) reacting a reaction product of the step (a) formed in the solvent, with hydrogen fluoride.

Abstract: An electrolyte for a lithium ion secondary battery includes a non-aqueous organic solvent; a lithium salt; and a phosphonitrile fluoride trimer as an additive, and a lithium ion secondary battery comprising the same. The thickness increase rate of a lithium ion secondary battery including the electrolyte is reduced even when the battery is kept at a high temperature. Thus, the thermal stability and durability of the battery are prominently improved. The durability of the battery can be further improved by including a vinylene carbonate or ethylene carbonate group compound in the electrolyte.

Abstract: A secondary battery having high cycle characteristics is provided. The secondary battery includes a cathode, an anode, and an electrolyte. In the anode, an anode active material layer containing silicon, carbon, and oxygen as an anode active material is provided on an anode current collector. In the anode active material, a content of carbon is from 0.2 atomic % to 10 atomic % both inclusive, and a content of oxygen is from 0.5 atomic % to 40 atomic % both inclusive. A ratio from 0.1% to 17.29% both inclusive of the silicon contained in the anode active material exists as Si—C bond.

Abstract: A non-aqueous electrolyte secondary battery includes a positive electrode, a negative electrode, a non-aqueous electrolyte, and an insulating layer formed on a surface of the positive electrode. The positive electrode includes a lithium nickel composite oxide having a layer structure, and the lithium nickel composite oxide is represented by the general formula: LixNiyM1?yO2 where M is at least one selected from the group consisting of Na, Mg, Sc, Y, Mn, Fe, Co, Cu, Zn, Al, Cr, Pb, Sb, and B, 0<x?1.2, and 0.5<y?1.0. The non-aqueous electrolyte includes a solute and a non-aqueous solvent dissolving the solute, and the non-aqueous solvent contains 40% by weight or more of a cyclic carbonic acid ester. The insulating layer includes an insulating polymeric material.

Abstract: In order to manufacture a lithium secondary battery having excellent performances in safety under overcharge condition, cycle property, electric capacity, and storage endurance, 0.1 wt. % to 10 wt. % of a tert-alkylbenzene compound is favorably incorporated into a non-aqueous electrolytic solution comprising a non-aqueous solvent and an electrolyte, preferably in combination with 0.1 wt. % to 1.5 wt. % of a biphenyl compound.

Abstract: A rechargeable lithium-ion cell contains a positive electrode, negative electrode, charge-carrying electrolyte containing charge carrying medium and lithium salt, and cycloaliphatic N-oxide compound dissolved in or dissolvable in the electrolyte. The N-oxide compound has an oxidation potential above the positive electrode recharged potential and serves as a cyclable redox chemical shuttle providing cell overcharge protection.

Abstract: A rechargeable lithium-ion cell contains a positive electrode, negative electrode, charge-carrying electrolyte containing charge carrying medium and lithium salt, and an N-substituted or C-substituted phenothiazine compound dissolved in or dissolvable in the electrolyte. The substituted phenothiazine compound has an oxidation potential above the positive electrode recharged potential and serves as a cyclable redox chemical shuttle providing cell overcharge protection.

Abstract: A secondary battery capable of improving the cycle characteristics is provided. The secondary battery includes a cathode, an anode, and an electrolytic solution. The electrolytic solution is impregnated in a separator provided between the cathode and the anode. The anode has an anode structure on an anode current collector. The anode structure has a structure in which a plurality of anode active material particles having silicon are held by a plurality of metal fibers forming a three-dimensional network structure. Due to the plurality of metal fibers, sufficient conductive paths are obtained among the plurality of anode active material particles. Thus, compared to a general anode in which an active material layer is provided on a current collector made of a metal foil or the like, the current collectivity is improved.

Abstract: The invention relates to an aprotic polymer/molten salt ternary mixture solvent and to a corresponding quaternary mixture additionally comprising an ionic conducting salt, which are prepared by mixing the constituents of the mixture. These mixtures are advantageously used in the preparation of electrochemical membranes, electrochemical systems and of electrochromic systems. The invention also relates to electrochemical and electrochromic systems obtained hereby that exhibit, in particular, excellent electrochemical properties at low temperatures.

Abstract: The present invention provides a nonaqueous electrolytic solution which can give excellent cycle characteristics. The nonaqueous electrolytic solution contains a linear carbonate represented by the formula (1): wherein, in the formula (1), Xa represents each independently hydrogen or any group; Ra represents optionally substituted alkyl; and n represents an integer of zero or more.

Abstract: An electrochemical cell with an alkali metal containing anode having high discharge capacity, charge efficiency and low self-discharge. The addition of at least one nitramide or dinitramide salt of a metal cation to the electrochemical cell electrolyte unexpectedly lowers first cycle irreversible capacity, adds higher cycle life, lowers self-discharge and beneficially addresses several additional degrees of freedom with respect to electrolyte solvent selection while providing higher charge capacity. Additives include the lithium metal salts of nitramide or dinitramide, and the electrolyte consists essentially of a lithium metal salt dissolved in a at least one of an aqueous solvent, molten salt solvent system and a non-aqueous solvent mixture of at least one of organic ethers, esters, carbonates, acetals.

Abstract: A separator is disclosed which enables to inject a non-aqueous electrolytic solution easily during production of batteries such as lithium ion secondary batteries and also enables to produce a battery which is excellent in various battery performances. The battery separator comprises a long porous film in which plural non-porous linear regions are arranged in a width direction of the film, at least one surface of the linear regions being a concave or convex surface is advantageously used as a battery separator for lithium secondary batteries or the like.

Abstract: A primary cell having an anode comprising lithium and a cathode comprising iron disulfide (FeS2) and carbon particles. The electrolyte comprises a lithium salt dissolved in a nonaqueous solvent mixture which contains an additive, preferably iodine, suppressing voltage delay. A cathode slurry is prepared comprising iron disulfide powder, carbon, binder, and liquid solvent. The mixture is coated onto a conductive substrate and solvent evaporated leaving a dry cathode coating on the substrate. The anode and cathode can be spirally wound with separator therebetween and inserted into the cell casing with electrolyte then added.

Abstract: An electrolyte for a lithium ion secondary battery includes a non-aqueous organic solvent; lithium salt; and difluoro oxalato borate and fluoro ethylene carbonate (FEC). The capacity retention property and durability of a lithium ion secondary battery including the electrolyte is excellent even when the battery is left at a high temperature.

Abstract: A secondary battery capable of improving the cycle characteristics while securing the initial charge and discharge characteristics is provided. The secondary battery includes a cathode, an anode, and an electrolytic solution. The anode has an anode active material layer containing a plurality of anode active material particles having silicon (Si). The anode active material layer contains at least one of an oxide-containing film covering a surface of the anode active material particles and a metal material not being alloyed with an electrode reactant provided in a gap in the anode active material layer. The electrolytic solution contains a solvent containing an organic acid that has a portion including an electron attractive group such as —(O?)C—C(?O)— bond in the center and a hydroxyl group on the both ends.

Abstract: The invention relates to a nonaqueous electrolyte which comprises a nonaqueous organic solvent and a lithium salt dissolved therein, wherein the nonaqueous organic solvent contains at least one compound selected from the group consisting of acid anhydrides and carbonic esters having an unsaturated bond, and at least one compound selected from the group consisting of sulfonic compounds and fluorine-containing aromatic compounds having 9 carbon atoms or less; and a lithium secondary battery employing the same.

Abstract: The invention provides composite graphite particles, comprising a core material consisting of graphite having a interlayer distance d(002) of 0.337 nm or less and a surface layer consisting of graphite in which the intensity ratio ID/IG (R value) between the peak intensities (ID) in a range of 1300 to 1400 cm?1 and ( IG) in a range of 1580 to 1620 cm?1 as measured by Raman scattering spectroscopy is 0.3 or higher, wherein the peak intensity ratio I110/I004 between the peak intensities (I110)of face (110) and (I004)of face (004) obtained by XRD measurement on the graphite crystal is 0.15 or higher when the graphite has been mixed with a binder and pressure-molded to a density of 1.55 to 1.

Abstract: An electrolyte for a lithium battery and a lithium battery thereof are provided. The electrolyte includes a non-aqueous organic solvent; lithium salt; and an additive selected from the group consisting of the compounds represented by formulas (1) to (3), and combinations thereof: where X is selected from the group consisting of hydrogen, halogen, alkyl groups having from 1 to 6 carbon atoms, and aryl groups having from 6 to 8 carbon atoms, and R is an alkyl group having from 1 to 6 carbon atoms or an aryl group having from 6 to 10 carbon atoms. The lithium battery including the electrolyte suggested in the present invention has superior overcharge characteristics and superior safety characteristics compared to conventional batteries including a non-aqueous electrolyte.

Abstract: A battery is provided. The battery includes an electrolytic solution, a positive electrode and a negative electrode. The negative electrode has a negative electrode active material layer containing a carbon material and having a thickness per one face of 70 ?m or more and not more than 120 ?m. The electrolytic solution contains a solvent containing 15% by mass or more and not more than 30% by mass of a cyclic carbonate represented by the following formula (1): wherein R1 to R4 each independently represents hydrogen, a halogen, an alkyl group or a halogenated alkyl group. A mass content ratio (B/A) of a halogenated cyclic carbonate (B % by mass) contained in the cyclic carbonate (A % by mass) which is represented by the formula (1) being from 0.5 to 1.

Abstract: A life of a secondary battery is extended, increase in a resistance when storing a secondary battery at an elevated temperature is prevented, and increase in a resistance during a charge-discharge cycle is prevented. A positive electrode active material comprising a lithium manganate and a lithium nickelate are used. The lithium manganate is a compound represented by the following formula (1) or the compound in which some of Mn or O sites are replaced with another element: Li1+xMn2?xO4??(1) (in the above-shown formula (1), 0.15?x?0.24).

Abstract: A battery capable of improving the cycle characteristics is provided. The battery includes a cathode and an anode oppositely arranged with a separator in between, and an electrolytic solution. At least one of the cathode, the anode, the separator, and the electrolytic solution contains a sulfone compound having an acid anhydride group and a sulfonyl group.

Abstract: A cyclic carbonate-modified silane or siloxane is combined with a non-aqueous solvent and an electrolyte salt to form a non-aqueous electrolytic solution, which is used to construct a secondary battery having improved temperature and high-output characteristics.

Abstract: A non-aqueous electrolyte of the present invention contains a lithium salt (A), a quaternary ammonium salt (B) containing a straight chain alkyl group having carbon atoms of 4 or less and a solvent (C) composed of at least one compound selected from the group consisting of ethylene carbonate, propylene carbonate, butylene carbonate, ?-butyrolactone, dimethyl carbonate, ethyl methyl carbonate, diethyl carbonate, dimethoxyethane, ethoxymethoxyethane and diethoxyethane. The molar ratio C/A of the solvent (C) to the lithium salt (A) or the molar ratio C/B of the solvent (C) to the ammonium salt (B) is 6 or less. The non-aqueous electrolyte has a single phase. Consequently, there can be obtained a non-aqueous electrolyte of a high ion concentration having an excellent oxidation resistance and reduction resistance.

Abstract: Organic lithium salts suitable for use in electrolytes for primary or secondary rechargeable batteries include de-localized bulky anions over Lewis acid fragments, typically BF3, and organic moieties. The organic moieties may be, for example, anions derived from fused nitrogen heterocycles (e.g. benzeneimidate, benzitriazolate and the like); multi carboxylates (e.g. oxalate, 1,2,4,5-benzenetetracarboxylate and the like), and pyromellitic diimidate. The organic lithium salts of the invention have the general formula: Liq[Org(MXn)m], in which Org represents the organic moieties and MXn represents an organic or inorganic boron, aluminum or phosphorous containing Lewis acid.

Abstract: The present application provides a nonaqueous electrolyte secondary battery that includes, a cathode capable of being electrochemically doped/dedoped with lithium, an anode capable of being electrochemically doped/dedoped with lithium, and an electrolyte placed between the cathode and the anode, wherein the electrolyte contains at least one of fluoro ethylene carbonate represented by Chemical Formula (1) and difluoro ethylene carbonate represented by Chemical Formula (2) as a solvent and the ratio of a discharge capacity B during discharging at a 5C rate to a discharge capacity A during discharging at a 0.2C rate ((B/A)×100) is 80% or more.

Abstract: A battery capable of improving the cycle characteristics is provided. The battery includes a cathode, an anode, and an electrolytic solution. The anode has an anode active material layer that contains an anode active material containing silicon on an anode current collector, and intensity ratio I1/I2 between peak intensity I1 originated in (220) crystalline plane of silicon obtained by X-ray diffraction and peak intensity I2 originated in (111) crystalline plane of silicon obtained by X-ray diffraction is 0.05 or more.

Abstract: Electrochemical cells are disclosed. In some embodiments, an electrochemical cell includes a cathode having less than about 2,000 ppm of water, an anode, and an electrolyte having a first lithium salt and LiPF6.

Abstract: The invention relates to a pasty material that can be used in electrochemical components comprising (A) 0-70 percent by weight of a matrix containing at least one organic polymer, its precursors or its prepolymers or consisting thereof; (B) 30-100 percent by weight of inorganic material that can be electrochemically activated and that is preferably nonsoluble in the matrix in the form of a solid substance and optionally a suspending agent for (B). The invention is characterized in that the electrochemically activatable material is at least partially a nanocrystalline powder, with the proviso that material (B) is not a material that can be used as electrode material in the absence of (A). Said material is suitable for producing self-supporting layers or layers placed on a substrate, from which or with which layered composites with electrochemical properties such as accumulators, batteries, condensers (supercaps), solar cells and electrochrome display elements can be produced.

Abstract: Disclosed is an electrolyte of a lithium secondary battery comprising a lithium salt, an organic solvent, and at least one additive compound selected from the group consisting of compounds represented by the following formula (1) and derivatives thereof: where R1 is selected from the group consisting of hydrogen radicals, alkyls aryls, cycloalkyls, alkenyls, alkynyls, ester radicals, and aliphatic carbonate radicals. The electrolyte improves both swelling inhibition properties at high temperature and capacity characteristics of a lithium secondary battery.

Abstract: The rechargeable lithium battery includes: a negative electrode including a non-carbon-based negative active material; a positive electrode including a positive active material that reversibly intercalates and deintercalates lithium ions; and an electrolyte that includes a non-aqueous organic solvent that includes ethylene carbonate in an amount of 20 volume % or less, a lithium salt including LiPF6, a first additive represented by the following Formula 1 and a second additive that is LiB(C2O4)2. The electrolyte has a viscosity of 3.02 cP or less: wherein, R1 and R2 are independently selected from the group consisting of hydrogen, a halogen, a cyano (CN), a nitro (NO2), and a C1 to C5 fluoroalkyl, provided that at least one of R1 and R2 is selected from the group consisting of a halogen, a cyano (CN), a nitro (NO2), and a C1 to C5 fluoroalkyl.

Abstract: An anode for secondary battery is provided with an anode active material layer containing silicon on an anode current collector. Silicon in the anode active material has an amorphous structure. In a Raman spectrum of silicon having the amorphous structure after an initial charge and discharge, 0.25?LA/TO and/or 45?LO/TO is satisfied, where an intensity of a scattering peak occurred in the vicinity of shift position 480 cm?1 based on scattering due to transverse optical phonon is TO, an intensity of a scattering peak occurred in the vicinity of shift position 300 cm?1 based on scattering due to longitudinal acoustic phonon is LA, and an intensity of a scattering peak occurred in the vicinity of shift position 400 cm?1 based on scattering due to longitudinal optical phonon is LO.

Abstract: A battery capable of improving the cycle characteristics is provided. A current collector containing copper (Cu), in which ratio I(200)/I(111) between intensity I (200) of a peak originated in (200) crystal plane of copper obtained by X-ray diffraction and intensity I (111) of a peak originated in (111) crystal plane thereof is in the range from 0.5 to 1.5.

Abstract: A nonaqueous electrolyte secondary battery is provided with a positive electrode including a positive-electrode active material, a negative electrode including a negative-electrode active material, and a nonaqueous electrolyte solution. The negative electrode further includes carbon fibers and carbon flakes. The synergistic effects of the improved retention of the electrolyte solution by the carbon fibers and the improved conductivity between the active material particles by the carbon flakes facilitate doping/undoping of lithium in a high-load current mode and increase the capacity of the battery in the high-load current mode.

Abstract: A material (hereinafter referred to as “positive electrode material”) including sodium manganate powder as a positive electrode active material, carbon black powder as a conductive agent, and polytetrafluoroethylene as a binder is prepared. The positive electrode material is mixed in an N-methylpyrrolidone solution to produce slurry as a positive electrode mixture. A working electrode is produced by applying the slurry on a positive electrode collector. A negative electrode containing tin or germanium is produced. The non-aqueous electrolyte is produced by adding sodium hexafluorophosphate as an electrolyte salt in a non-aqueous solvent produced by mixing ethylenecarbonate and diethyl carbonate.

Abstract: An electrolyte for a lithium secondary battery which has a non-aqueous organic solvent including a ?-butyrolactone and optionally a cyclic carbonate, an ester compound having an electron withdrawing group, and at least two salts. The lithium secondary battery including the electrolyte has good safety and good storage characteristics at high temperature.

Abstract: The invention relates to an aprotic polymer/molten salt ternary mixture solvent and to a corresponding quaternary mixture additionally comprising an ionic conducting salt, which are prepared by mixing the constituents of the mixture. These mixtures are advantageously used in the preparation of electrochemical membranes, electrochemical systems and of electrochromic systems. The invention also relates to electrochemical and electrochromic systems obtained hereby that exhibit, in particular, excellent electrochemical properties at low temperatures.

Abstract: A secondary cell employs a nonaqueous electrolyte solution including a nonaqueous solvent and a salt, and a flame retardant material that is liquid at room temperature and pressure and substantially immiscible in the nonaqueous electrolyte solution. The nonaqueous electrolyte solution is formed by dissolving a salt, preferably an alkali metal salt, in a nonaqueous solvent. The nonaqueous solvent preferably includes a cyclic carbonate and/or a linear carbonate. The cyclic carbonate preferably contains an alkylene group with 2 to 5 carbon atoms, and the linear carbonate preferably contains a hydrocarbon group with 1 to 5 carbon atoms. Preferred salts include LiPF6 and LiBF4 at a concentration between about 0.1 and 3.0 moles/liter. The flame retardant material is preferably a halogen-containing compound in an amount by weight of nonaqueous solvent in a range of about 1 to about 99 wt %, and preferred halogen-containing compounds contain perfluoralkyl or perfluorether groups.

Abstract: Electrochemical cells are disclosed. In some embodiments, an electrochemical cell includes a cathode, an anode, and an electrolyte having a first lithium salt and LiBF4.

Abstract: Non-aqueous electrolyte solutions capable of protecting negative electrode materials such as lithium metal and carbonaceous materials in energy storage electrochemical cells (e.g., lithium metal batteries, lithium ion batteries and supercapacitors) include an electrolyte salt, a non-aqueous electrolyte solvent mixture, an unsaturated organic compound 4-methylene-1,3-dioxolan-2-one or 4,5-dimethylene-1,3-dioxolan-2-one, and other optional additives. The 1,3-dioxolan-2-ones help to form a good solid electrolyte interface on the negative electrode surface.

Abstract: The battery has an electrode assembly that includes one or more anodes and one or more cathodes. A first liquid phase is positioned in an active region of the electrode assembly. The first liquid phase includes one or more first flame retardants and an electrolyte. A second liquid phase is outside of the active region and in contact with the first liquid phase. The second liquid phase includes one or more second flame retardants. A third liquid phase is outside of the active region and in contact with the second liquid phase. The third liquid phase includes one or more third flame retardants. The first liquid phase and/or the electrolyte have a density between the second liquid phase and the third liquid phase.

Abstract: Disclosed is a non-aqueous electrolyte comprising: a non-aqueous cyclic solvent; a catalyst for polymerization, which is activated depending on temperature or voltage to induce the polymerization of the non-aqueous cyclic solvent; and an electrolyte salt. Also, a secondary battery comprising the non-aqueous electrolyte is disclosed. The non-aqueous electrolyte does not influence the performance of the battery at the normal operating temperature and voltage of the secondary battery. However, when the battery misoperates due to high temperature or overcharge, the polymerization of the non-aqueous cyclic solvent can occur due to the catalyst for polymerization contained in the non-aqueous electrolyte, at a specific temperature or voltage, to increase the resistance of the electrolyte and reduce the ion conductivity of the electrolyte, thus increasing the safety of the battery.