Abstract: The subject of the invention is an anode material of the silicon-carbon composite type, for a lithium cell, having a high mass capacity and good cycling stability. This material is obtained by a preparation method comprising the steps consisting of: a) providing a silicon powder obtained by the plasma-enhanced chemical vapor deposition (PECVD) technique or by CO2 laser, the size of the silicon particles being less than 100 nm; b) mixing the silicon powder with a carbon-containing polymer, and c) carrying out the pyrolysis of the mixture. The invention also proposes a lithium cell containing at least one anode the material of which contains the nanocomposite material produced by this method.

Abstract: A nonaqueous electrolyte and a lithium-ion secondary battery using the same, wherein a mixture of a cyclic carbonate, a chain carbonate, a first phosphoric acid ester wherein bonding between carbons is a single bond, and a second phosphoric acid ester wherein bonding between carbons contains a double bond is used as the nonaqueous electrolyte. It is desirable that the first phosphoric acid ester is a trimethyl phosphate. In addition, it is desirable that the second phosphoric acid ester is a dimethylisopropenyl phosphate.

Abstract: A series of polar and aprotic organic molecules, which, when used as solvents or additives in nonaqueous electrolytes, afford improved performance for electrochemical cells that operate at high voltages. These polar and aprotic solvents or additives may contain at least one unsaturated functionality per molecule. The unsaturated functionality is conjugated with the polar functionality of the molecule. The unsaturated functionality that is either a double or triple bond could be between carbon-carbon, or between carbon-heteroatom, or between hetroatom-heteroatom. Nonaqueous electrolyte solutions are provided comprising one or more lithium salts dissolved in the mixture solvents, which comprises, in all possible ratios, at least one of the polar, aprotic and unsaturated solvent or additives, one or more cyclic carbonic diesters such as ethylene carbonate, and one or more acyclic carbonic diesters such as dimethyl carbonate, diethyl carbonate, and ethylmethyl carbonate.

Abstract: A non-aqueous electrolyte secondary battery has a high initial capacity and excels in cycle characteristics and storage characteristics even when charged until the potential of the positive electrode active material exceeds as high as 4.3V versus lithium. The non-aqueous electrolyte of the secondary battery contains both 1,3-dioxane and a sulfonic acid ester compound.

Abstract: Organic electrolytic solutions and lithium batteries using the organic electrolytic solutions are provided. One organic electrolytic solution includes a lithium salt, a mixed organic solvent consisting of a high-dielectric constant solvent and a low-boiling point solvent, and a compound represented by Formula 1 or 2 as an additive. The organic electrolytic solution and the lithium battery using the organic electrolytic solution may inhibit the reductive cleavage reaction of a polar solvent, thereby increasing capacity retention of the battery, and improving charge-discharge efficiency and battery lifetime.

Abstract: An electrolyte for a lithium ion secondary battery and a lithium ion secondary battery comprising the electrolyte. The electrolyte comprises a non-aqueous organic solvent, a lithium salt, and at least one aromatic phosphate compound. Exothermic reactions are inhibited in the battery upon overcharge or during high-temperature storage to prevent an increase in the temperature of the battery, resulting in an improvement in safety. In addition, the battery exhibits good swelling stability during high-temperature storage as well as improved cycle life characteristics. The electrolyte further comprises an ethylene carbonate-based compound. The presence of the ethylene carbonate-based compound leads to further improvements in the overcharge safety, high-temperature safety and cycle life characteristics of the battery.

Abstract: The sudden generation of heat being frequently caused in the case of the overcharge of a lithium secondary cell which have a positive electrode comprising a composite metal oxide of lithium and cobalt or a composite metal oxide of lithium and nickel, a negative electrode comprising metallic lithium, a lithium alloy or a material capable of occluding and releasing lithium, and a nonaqueous electrolyte solution comprising a nonaqueous solvent and an electrolyte dissolved therein can be efficiently prevented by the addition, to the nonaqueous electrolyte solution, of an organic compound which, when the lithium secondary cell is overcharged, decomposes into a decomposition product capable of dissolving out the cobalt or nickel contained in the positive electrode and depositing it ion the negative electrode (for example, a tert-alkylbenzene derivative).

Abstract: Organic electrolyte solutions and lithium batteries using the same are provided. The organic electrolyte solutions use a silane compound that prevents crack formation caused by volumetric changes in the anode active material during battery charging/discharging. This improves charge/discharge characteristics, thereby also improving stability, reliability, and charge/discharge efficiency of the battery.

Abstract: Disclosed are a non-aqueous electrolyte solution for a lithium secondary battery and a lithium secondary battery comprising the same. The non-aqueous electrolyte solution for a lithium secondary battery may include difluorotoluene having a lowest oxidation potential among components of the non-aqueous electrolyte solution. The lithium secondary battery may have improvement in basic performance including high rate charge/discharge characteristics, cycle life characteristics, and the like, and may remarkably reduce swelling caused by decomposition of an electrolyte solution under high voltage conditions such as overcharge.

Abstract: The nonaqueous solvent for a nonaqueous secondary battery of the present invention includes: a fluorinated cyclic carbonate having at least one fluorine in each designated location in the molecule; and a fluorinated phosphazene having at least one fluorine bound to a phosphorus atom in the phosphazene molecule and a ratio of the number of fluorine atoms to the number of phosphorus atoms being 4/3 or more. The fluorinated cyclic carbonate forms a good protective coat by reductive decomposition at a negative electrode, thereby improving cycle characteristics of the nonaqueous secondary battery. The fluorinated phosphazene suppresses generation of organic ions in the nonaqueous solvent, thereby reducing gas production in the nonaqueous secondary battery.

Abstract: A nonaqueous electrolyte secondary battery of the invention has a positive electrode having a positive electrode active material, a negative electrode, and a nonaqueous electrolyte having electrolyte salt in a nonaqueous solvent. The electric potential of the positive electrode active material is 4.4 to 4.6 V relative to lithium, and the nonaqueous electrolyte contains a compound expressed by structural formula (I) below. The quantity of compound added is preferably 0.1% to 2% by mass. Also, the positive electrode active material preferably comprises a mixture of a lithium-cobalt composite oxide which is LiCoO2 containing at least both zirconium and magnesium and a lithium-manganese-nickel composite oxide that has a layer structure and contains at least both manganese and nickel. Thanks to such structure, a nonaqueous electrolyte secondary battery can be provided that is charged to charging termination potential of 4.4 to 4.6 V relative to lithium and that has enhanced overcharging safety.

Abstract: A nonaqueous electrolyte which contains a nonaqueous organic solvent and a lithium salt dissolved therein is provided. Also provided is a lithium secondary battery employing the nonaqueous electrolyte.

Abstract: The preservation performance of a nonaqueous electrolyte secondary cell charged to high potential is improved while the initial capacity and the cycle property of the cell are also improved. The nonaqueous electrolyte secondary cell includes: a positive electrode having lithium phosphate and a positive electrode active material containing lithium cobalt compound oxide and lithium manganese nickel compound oxide having a layer structure, the lithium cobalt compound oxide having at least zirconium and magnesium added in LiCoO2; a negative electrode having a negative electrode active material; and a nonaqueous electrolyte having a nonaqueous solvent and an electrolytic salt. The potential of the positive electrode is more than 4.3 V and 5.1 V or less based on lithium. The nonaqueous electrolyte contains vinylene carbonate as the nonaqueous solvent and, as the electrolytic salt, at least one of lithium bis(pentafluoroethane sulfonyl)imide and lithium bis(trifluoromethane sulfonyl)imide at 0.1 M or more and 0.

Abstract: A positive electrode active material of a nonaqueous electrolyte secondary battery is composed of lithium-cobalt composite oxide containing at least one of zirconium, titanium, aluminum, and erbium, and the nonaqueous electrolyte includes an additive expressed by General Formula (1) having an acetylene group and a methylsulfonyl group at each end of the molecule. It has the effect of forming an SEI surface film as with the case of VC or the like, as well as having a higher oxidation resistance than that of VC or the like. Thus the nonaqueous electrolyte secondary battery employing as positive electrode active material a lithium-cobalt composite oxide with a particular dissimilar metallic element added, in which decomposition of the nonaqueous electrolytic solution during storage at high temperature in a charged state is suppressed, and there is little battery swelling is provided.

Abstract: A non-aqueous electrolyte solution is provided that realizes a large capacity, exhibits high storage characteristics and cycle characteristics, and is capable of inhibiting gas generation.

Abstract: There is provided an anode for a lithium ion secondary battery capable of improving the cycle characteristics, a lithium ion secondary battery using the same, an electric power tool using the lithium ion secondary battery, an electrical vehicle using the lithium ion secondary battery, and an electric power storage system using the lithium ion secondary battery. The anode for a lithium ion secondary battery includes an anode active material layer in which a first layer and a second layer respectively containing silicon and a metal element as an anode active material are alternately layered on an anode current collector, and 1.02?A/B?50 is satisfied. A represents a silicon content ratio in the anode active material in the first layer, and B represents a silicon content ratio in the anode active material in the second layer.

Abstract: Disclosed is a lithium battery including: a positive electrode including manganese dioxide as a positive electrode active material; a negative electrode including at least one selected from lithium metal and a lithium alloy, as a negative electrode active material; a porous insulating member interposed between the positive electrode and the negative electrode; and an organic electrolyte. The organic electrolyte contains 0.0008 to 1.2% by weight of an alkyl ester of an aliphatic hydroxycarboxylic acid. The alkyl ester may be a C1-6 alkyl ester of an aliphatic hydroxycarboxylic acid having 2 to 7 carbon atoms, such as a C1-4 alkyl 4-hydroxybutyrate.

Abstract: A solvent for a non-aqueous electrolytic solution providing a lithium secondary cell being specifically excellent in discharge capacity, rate characteristic and cycle characteristic and having improved incombustibility (safety), a non-aqueous electrolytic solution using the solvent, and further a lithium secondary cell are provided. The solvent for dissolving an electrolyte salt of a lithium secondary cell comprises at least one fluorine-containing solvent (I) selected from the group consisting of fluorine-containing ether, fluorine-containing ester and fluorine-containing chain carbonate, a fluorine-containing aromatic compound (II), in which a part or the whole of hydrogen atoms are replaced by fluorine atoms, and other carbonate (III), the non-aqueous electrolytic solution comprises the solvent and an electrolyte salt, and the lithium secondary cell uses the non-aqueous electrolytic solution.

Abstract: An organic electrolytic solution for a lithium primary or secondary battery includes a lithium salt; an organic solvent; a radical initiator represented by Formula 1 below; and a polymerizable monomer represented by Formula 2 below: R1—N2+X???<Formula 1> wherein R1, R2, R3, R4, and X? are described herein. The organic electrolytic solution improves charge-discharge efficiency and increases cell capacity of the lithium primary or secondary battery.

Abstract: An object of the present invention is to provide a lithium ion battery in which the deterioration during the high temperature storage is suppressed. The lithium ion battery is a lithium ion battery 100 having a cathode 3 capable of occluding and releasing lithium ions, an anode 6 capable of occluding and releasing lithium ions, a separator 7 disposed between the cathode 3 and the anode 6 and an organic electrolyte solution, wherein the organic electrolyte solution contains a plurality of solvents, an additive and an electrolyte, the electrolyte contains lithium hexafluorophosphate (LiPF6), and the additive contains vinylene carbonate or a derivative thereof and a compound represented by the following formula (I): wherein R1, R2 and R3 are each independently a fluorine atom or a fluorinated alkyl group having 1 to 3 carbon atoms.

Abstract: The present invention provides a lithium secondary battery having excellent battery characteristics such as battery cycling property, electrical capacity and storage property. The present invention relates to a nonaqueous electrolytic solution for lithium secondary batteries in which an electrolyte salt is dissolved in a nonaqueous solvent, the nonaqueous electrolytic solution comprising a formic ester compound having a specific structure in an amount of 0.01 to 10% by weight of the nonaqueous electrolytic solution, and a lithium secondary battery using the same.

Abstract: The present invention relates to an electrolyte for a lithium ion rechargeable battery and a lithium ion rechargeable battery including the same. The electrolyte includes a non-aqueous organic solvent, a lithium salt, and triphenyl phosphate. A lithium ion rechargeable battery including the electrolyte has improved overcharge stability and shows excellent chemical properties including reducing swelling, high-temperature storage stability, and cycle life characteristics.

Abstract: Disclosed is a lithium secondary battery comprising a cathode including a lithium-containing transition metal oxide, an anode including a carbon-based material, and a non-aqueous electrolyte with addition of a compound of formula (1). Incorporation of the compound (1) into the electrolyte significantly improves the high-temperature performance and cycle life characteristics of the battery.

Abstract: A cathode active material composition of a cathode of a lithium battery includes a conducting agent, a binder, and a cathode active material coated on one surface of a current collector, wherein the cathode active material composition is coated with a vanadium oxide.

Abstract: The present invention relates to non-aqueous electrolytes having stabilization additives and electrochemical devices containing the same. Thus the present invention provides electrolytes containing an alkali metal salt, a polar aprotic solvent, a first additive that is a substituted or unsubstituted organoamine, substituted or unsubstituted alkane, substituted or unsubstituted alkene, or substituted or unsubstituted aryl compound, and/or a second additive that is a metal(chelato)borate. When used in electrochemical devices with, e.g., lithium manganese oxide spinel electrodes, the new electrolytes provide batteries with improved calendar and cycle life.

Abstract: The present invention is made to improve charge-discharge cycle performances under high temperature environment in a non-aqueous electrolyte secondary battery using a negative electrode containing a negative electrode active material of particulate silicon and/or silicon alloy and a binding agent.

Abstract: The invention relates to an electrolyte composition consisting of an ionic liquid, a conducting salt, a film former and a viscosity modifier and also to the use of the electrolyte composition of the present invention as an electrolyte material for electrochemical energy storage systems, especially for lithium-metal and lithium-ion batteries.

Abstract: There is provided a non-aqueous electrolytic solution assuring good solubility of an electrolyte salt and having enough cell characteristics (charge and discharge cycle characteristic, discharge capacity, and the like), and the non-aqueous electrolytic solution comprises a solvent for dissolving an electrolyte salt comprising (A) at least one fluorine-containing solvent selected from the group consisting of fluorine-containing ethers and fluorine-containing carbonates, (B) a non-fluorine-containing cyclic carbonate and (C) a chain ester represented by the formula (C): R1COOR2, wherein R1 is an alkyl group having 2 to 4 carbon atoms; R2 is an alkyl group having 1 to 4 carbon atoms or a fluorine-containing alkyl group having 1 to 4 carbon atoms, and (II) an electrolyte salt.

Abstract: The present invention provides an electrolyte for lithium and lithium-ion batteries comprising a lithium salt such as LiF2BC2O4, LiPF6, LiBF4, and/or LiB(C2O4)2. In a liquid carrier comprising glycerol carbonate. Preferably, the electrolyte comprises a combination of glycerol carbonate with one or more other carbonate solvent (e.g., dimethylcarbonate, ethylene carbonate, and the like).

Abstract: A non-aqueous electrolyte for a secondary battery includes a solvent and an electrolyte containing a lithium salt. The solvent contains 4-fluoroethylene carbonate and a chain carboxylic ester represented by the formula R1COOR2, where R1 and R2 are alkyl groups having 3 or less carbon atoms. The amount of the 4-fluoroethylene carbonate is 7 volume % or greater with respect to the total amount of the solvent.

Abstract: A non-aqueous electrolyte includes (i) an inhibitor against a reaction between an anode and a linear ester; (ii) a mixed organic solvent containing cyclic carbonate and the linear ester; and (iii) an electrolyte salt, wherein the inhibitor is any one compound or a mixture of at least two compounds selected from the group consisting of cyclic carbonate with a vinyl group, fluorinated ethylene carbonate, vinylene carbonate, cyclic acid anhydride, a compound having a cyclic S?O group and an acrylate-based compound. Also, an electrochemical device includes a cathode, an anode and the above non-aqueous electrolyte.

Abstract: A non-aqueous electrolyte solution for a lithium secondary battery includes a lithium salt and an organic solvent. Based on 100 parts by weight of the non-aqueous electrolyte solution, the non-aqueous electrolyte solution includes 1 to 5 parts by weight of sultone-based compound having a carbon-carbon unsaturated bond in a cyclic structure; 1 to 5 parts by weight of cyclic carbonate compound with a vinyl group; 5 to 10 parts by weight of cyclic carbonate compound that is substituted with halogen; and 1 to 5 parts by weight of dinitrile-based compound. This non-aqueous electrolyte solution improves stability of a SEI film formed on a surface of an anode of a lithium secondary battery and thus improves normal temperature cycle performance and high temperature cycle performance.

Abstract: A cyclic carbonate monomer, including: wherein R1, R2, and R3 are independently selected from the group consisting of H, linear or branched, substituted or unsubstituted alkyl; R10 is a connecting group selected from the group consisting of linear or branched, substituted or unsubstituted alkyl, heteroalkyl, cycloalkyl, heterocyclic, aryl and heteroaryl; R4 is an optional bridging group selected from the group consisting of linear or branched, substituted or unsubstituted alkyl, heteroalkyl, cycloalkyl, heterocyclic, aryl and heteroaryl; Z is selected from the group consisting of O, NH, NR, and S; G is a guanidine group; and P is a protecting group. The cylic carbonate monomer can be reacted with an initiator including a drug, drug candidate, probe or other molecule of interest to form an oligomer with the molecule of interest attached to one end of a carbonate backbone and guanidine groups attached to the carbonate backbone.

Abstract: This invention relates to a non-aqueous electrolyte for a cell and an electrolyte for a polymer cell in which the risk of igniting-firing an aprotic organic solvent retained in the cell and leaked out of the cell through vaporization or the like when the temperature of the cell rises abnormally is reduced, and to a non-aqueous electrolyte for a cell and an electrolyte for a polymer cell comprising an aprotic organic solvent and a compound containing phosphorus and/or nitrogen in its molecule and having a difference of a boiling point from that of the aprotic organic solvent of not more than 25° C.

Abstract: A rechargeable lithium-ion battery includes a positive electrode that includes a first current collector and a first active material. The battery also includes an electrolyte and a negative electrode that includes a second current collector and a second active material, where the second active material includes a lithium titanate material. The positive electrode has a first capacity and the negative electrode has a second capacity, the second capacity being less than the first capacity such that the rechargeable lithium-ion battery is negative-limited.

Abstract: An electrochemical cell comprises as an anode, a lithium transition metal oxide or sulphide compound which has a [B2]X4n? spinel-type framework structure of an A[B2]X4 spinel wherein A and B are metal cations selected from Li, Ti, V, Mn, Fe and Co, X is oxygen or sulphur, and n? refers to the overall charge of the structural unit [B2]X4 of the framework structure. The transition metal cation in the fully discharged state has a mean oxidation state greater than +3 for Ti, +3 for V, +3.5 for Mn, +2 for Fe and +2 for Co. The cell includes as a cathode, a lithium metal oxide or sulphide compound. An electrically insulative lithium containing liquid or polymeric electronically conductive electrolyte is provided between the anode and the cathode.

Abstract: A rechargeable lithium battery including: a positive electrode including a nickel-based positive active material; a negative electrode including a negative active material; and an electrolyte including a non-aqueous organic solvent, a lithium salt, a first fluoroethylene carbonate additive, a second vinylethylene carbonate additive, and a third alkane sultone additive, wherein when the battery is thicker than about 5 mm, a mixing weight ratio of the first fluoroethylene carbonate additive to the second vinylethylene carbonate additive ranges from about 5:1 to about 10:1, or when the battery is thinner than about 5 mm, the mixing weight ratio of the first fluoroethylene carbonate additive to the second vinylethylene carbonate additive ranges from about 1:1 to about 4:1.

Abstract: An organic electrolytic solution and a lithium battery employing the same are provided. The organic electrolytic solution includes a lithium salt, an organic solvent containing a first solvent having a high dielectric constant and a second solvent having a low boiling point, and a surfactant including a hydrophobic portion having an aromatic group. The organic electrolytic solution effectively prevents the electrolytic solution from contacting the anode, thereby suppressing side reactions on the anode surface and improving discharge capacity, charge/discharge efficiency, lifespan, and battery reliability.

Abstract: A non-aqueous electrolyte includes an ionic electrolyte salt, and a non-aqueous electrolyte solvent that includes a mixture of siloxane or a silane or a mixture thereof, a sulfone, and a fluorinated ether or fluorinated ester or a mixture thereof, an ionic liquid, or a carbonate.

Abstract: A secondary battery and a method of manufacturing the same are disclosed. In one embodiment, the secondary battery includes an electrode assembly including an external surface, an electrolyte, a sealing tape including an adhesive layer attached to at least portion of an outer surface of the electrode assembly and contacting the external surface of the electrode assembly and a base sheet disposed on an adhesive layer and formed of a material having directionality, and a can receiving the electrode assembly, the electrolyte, and the sealing tape, wherein the base sheet loses directionality and is shrunk and deformed in shape by contact with the electrolyte, and at least portion of the base sheet contacts an inner surface of the can to prevent the electrode assembly from being freely moved within the can.

Abstract: Provided is a non-aqueous electrolyte capable of favorably suppressing the gas generation during storage in a high temperature environment and during charge/discharge cycling of a non-aqueous electrolyte secondary battery. The non-aqueous electrolyte includes a non-aqueous solvent and a solute dissolved in the non-aqueous solvent, wherein: the non-aqueous solvent includes ethylene carbonate, propylene carbonate, diethyl carbonate, and an additive; the additive includes a sultone compound and a cyclic carbonate having a C?C unsaturated bond; a weight percentage WPC of the propylene carbonate relative to a total of the ethylene carbonate, propylene carbonate, and diethyl carbonate is 30 to 60% by weight; a ratio WPC/WEC of the weight percentage WPC of the propylene carbonate to a weight percentage WEC of the ethylene carbonate relative to the total satisfies 2.

Abstract: An electrolyte for a rechargeable lithium battery according to one embodiment of the present invention includes a modified polyether silicone oil, a carbonate, and a lithium salt. The electrolyte has improved thermal stability and lithium ion conductivity.

Abstract: To provide a high-capacity non-aqueous electrolyte secondary battery that exhibits satisfactory charge/discharge cycle characteristics even in a high temperature environment. The battery has: a positive electrode including a nickel-containing lithium composite oxide; a negative electrode capable of charging and discharging; a separator interposed between the positive and negative electrodes; and a non-aqueous electrolyte containing a non-aqueous solvent and a solute dissolved therein. The non-aqueous electrolyte contains a fluorine atom-containing aromatic compound. The nickel-containing lithium composite oxide is represented by, for example, LiNixM1-x-yLyO2 where element M is at least one selected from the group consisting of Co and Mn; element L is at least one selected from the group consisting of Al, Sr, Y, Zr, Ta, Mg, Ti, Zn, B, Ca, Cr, Si, Ga, Sn, P, V, Sb, Nb, Mo, W and Fe; and x and y satisfy 0.1?x?1 and 0?y?0.1.

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 nonaqueous electrolyte battery includes a negative electrode including a current collector and a negative electrode active material having a Li ion insertion potential not lower than 0.4V (vs. Li/Li+). The negative electrode has a porous structure. A pore diameter distribution of the negative electrode as determined by a mercury porosimetry, which includes a first peak having a mode diameter of 0.01 to 0.2 ?m, and a second peak having a mode diameter of 0.003 to 0.02 ?m. A volume of pores having a diameter of 0.01 to 0.2 ?m as determined by the mercury porosimetry is 0.05 to 0.5 mL per gram of the negative electrode excluding the weight of the current collector. A volume of pores having a diameter of 0.003 to 0.02 ?m as determined by the mercury porosimetry is 0.0001 to 0.02 mL per gram of the negative electrode excluding the weight of the current collector.

Abstract: A process is provided to produce non-aqueous electrolytic solution for use in batteries having low acid content and low water content. The invention involves removing acids and water from non-aqueous electrolytic solutions typically found in lithium or lithium-ion batteries by using nitrogen-containing compounds such as triazines. After treatment by a triazine such as melamine, the concentrations of acids and water in the electrolytic solutions are substantially decreased. The present invention provides a process to prepare extremely pure electrolytic solutions having low (<20 ppm) concentrations of both water and acids.

Abstract: A nonaqueous electrolyte for a lithium secondary battery and a lithium secondary battery including the same are provided. In particular, the nonaqueous electrolyte comprises a compound of chemical formula 1 as an electrolyte additive: NC—(R1)n-A-(R2)m—CN??1 wherein, R1 and R2 represent, respectively, alkylene groups, n and m represent integers of 1 to 10, and A is an aromatic hydrocarbon in which the number of carbons is 5 to 9 or O. When the lithium secondary battery is kept at high voltage and temperature, the electrolyte additive reduces gas generation, thereby reducing battery swelling. Therefore, it is possible to reduce a battery thickness increment rate and to increase discharge capacity at a high temperature.

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: An organic electrolytic solution is provided which includes a lithium salt, an organic solvent including a first solvent having high permittivity and a second solvent having a low boiling point, and a phosphine oxide compound The phosphine oxide compound imparts flame resistance and good charge/discharge properties, thereby producing a lithium battery that is highly stable and reliable and that has good charge/discharge efficiency.

Abstract: In a rechargeable non-aqueous electrolyte secondary battery using positive electrodes, negative electrodes and a non-aqueous electrolytic solution, additives to the electrolytic solution are used in combination, preferably in combination of at least two compounds selected from o-terphenyl, triphenylene, cyclohexylbenzene and biphenyl, and thus there are provided batteries excellent in safety and storage characteristics.