Abstract: The present invention provides a non-aqueous electrolyte secondary battery comprising a positive electrode, a negative electrode, a separator, and a non-aqueous electrolyte, wherein the non-aqueous electrolyte comprises a non-aqueous solvent and lithium salt as an electrolyte, and wherein the non-aqueous solvent contains chain fluorinated carboxylic acid ester represented by the formula CH3COOCH2CH3-xFx (wherein x is 2 or 3) and a film forming chemical decomposed in the range of +1.0 to 3.0 V based on an equilibrium potential between metal lithium and lithium ion.

Abstract: A positive electrode for a non-aqueous electrolyte secondary battery, having a positive electrode current collector and a positive electrode active material layer formed on the positive electrode current collector and containing LiCoO2 as an active material, PVDF as a binder agent, acetylene black as a conductive agent, and LiCF3SO3.

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: To provide a positive electrode for a nonaqueous electrolyte secondary battery having excellent flexibility and capable of increasing the reliability and productivity, and a nonaqueous electrolyte secondary battery using the positive electrode. The positive electrode for a nonaqueous electrolyte secondary battery includes an active material layer that contains: a positive-electrode active material; a binder made of a fluorine-contained resin containing a vinylidene fluoride unit; and an electrolyte represented by one of the following general formulae (1) and (2): wherein M represents a metal element, R1 and R2 each represent fluorine or a fluorinated alkyl group having one to three carbon atoms and are identical to or different from each other, and n represents an integer of 1 to 3; wherein M represents a metal element, R3 represents a fluorinated alkylene group having two to four carbon atoms, and n represents an integer of 1 to 3.

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: The present invention provides a non-aqueous electrolyte secondary battery wherein a reaction between a non-aqueous electrolyte and an electrode is suppressed and decrease in battery capacity under high temperature is restricted, so that long time excellent battery characteristics can be obtained. A non-aqueous solvent of the non-aqueous electrolyte contains: chain fluorinated carboxylic acid ester represented by the formula R1-CH2—COO—R2 where R1 represents hydrogen or alkyl group and R2 represents alkyl group and the sum of the carbon numbers of R1 and R2 is 3 or less, and in the case that R1 is hydrogen, at least one part of hydrogen in R2 is replaced with fluorine, and, in the case that R1 is alkyl group, at least one part of hydrogen in R1 and/or R2 is replaced with fluorine; and a film forming chemical compound decomposed in the range of +1.0 to 3.0 V based on an equilibrium potential between metal lithium and lithium ion.

Abstract: The present invention provides a non-aqueous electrolyte secondary battery comprising a positive electrode, a negative electrode, a separator, and a non-aqueous electrolyte, wherein the non-aqueous electrolyte comprises a non-aqueous solvent and lithium salt as an electrolyte, and wherein the non-aqueous solvent contains chain fluorinated carboxylic acid ester represented by the formula CH3COOCH2CH3-xFx (wherein x is 2 or 3) and a film forming chemical decomposed in the range of +1.0 to 3.0 V based on an equilibrium potential between metal lithium and lithium ion.

Abstract: A non-aqueous electrolyte secondary battery includes a positive electrode, a negative electrode, and a non-aqueous electrolyte comprising an electrolyte dissolved in a non-aqueous solvent. The negative electrode uses a low crystalline carbon coated graphite in which at least part of the surface of graphite is coated with a low crystalline carbon material having lower crystallinity than that of graphite as a negative electrode active material, and the non-aqueous electrolyte comprises a lithium salt which has oxalate complex as an anion, in addition to a mixed solvent of propylene carbonate and chain carbonate as a non-aqueous solvent.

Abstract: A nonaqueous electrolyte secondary battery including a positive electrode 2 containing a positive electrode active material comprising a lithium-transition metal oxide having a layered structure, a negative electrode 1 and a nonaqueous electrolyte, wherein a surface treatment layer containing a compound represented by the chemical formula MlPmOn (wherein M is at least one element which can have a valence of 2, and l, m and n are integers in a range satisfying 2l+5m=2n) is formed on at least a part of the surface of the positive electrode active material.

Abstract: A nonaqueous electrolyte secondary battery is obtained which shows good cycle characteristics even when charged to a high voltage. The nonaqueous electrolyte secondary battery has a positive electrode containing a positive active material, a negative electrode containing a negative active material and a nonaqueous electrolyte, wherein a lithium-containing transition metal oxide having a layered structure is contained in the positive electrode as the positive active material, an additive which is reductively decomposed in the range of +3.0-1.3 V versus metallic lithium is contained in the nonaqueous electrolyte, and the battery after assembled is overdischarged until a potential of the positive electrode falls down to a reductive potential of the additive or below.

Abstract: A nonaqueous electrolyte secondary battery which includes a positive electrode, a negative electrode and a separator stacked and wound in a cylindrical configuration, and which achieves a high energy density and superior cycle performance characteristics. The nonaqueous electrolyte secondary battery includes a positive electrode containing a positive active material, a negative electrode containing a negative active material, a separator interposed between the positive electrode and the negative electrode, and a nonaqueous electrolyte containing a solvent and a solute. Those positive electrode, negative electrode and separator are stacked and wound in a cylindrical configuration. Characteristically, the negative active material comprises a material that stores lithium via alloying with lithium, the solvent in the nonaqueous electrolyte contains a fluorinated cyclic carbonate, and the nonaqueous electrolyte has a viscosity of not higher than 2.5 mPas.

Abstract: A non-aqueous electrolyte secondary battery includes a positive electrode, a negative electrode, and a non-aqueous electrolyte comprising an electrolyte dissolved in a non-aqueous solvent. The negative electrode uses a low crystalline carbon coated graphite in which at least part of the surface of graphite is coated with a low crystalline carbon material having lower crystallinity than that of graphite as a negative electrode active material, and the non-aqueous electrolyte comprises a lithium salt which has oxalate complex as an anion, in addition to a mixed solvent of propylene carbonate and chain carbonate as a non-aqueous solvent.

Abstract: A positive electrode material for a nonaqueous electrolyte secondary battery is obtained which attains good thermal stability and high discharge capacity and shows satisfactory charge-discharge cycle performance characteristics. A nonaqueous electrolyte secondary battery using the positive electrode material is also obtained. Characteristically, the positive electrode material for a nonaqueous electrolyte secondary battery contains a positive active material (e.g., lithium-containing layered complex oxide) capable of lithium storage and release, a lithium phosphate compound such as Li3PO4, and Al2O3. The lithium phosphate compound and Al2O3 are preferably disposed near the positive active material.

Abstract: Cycle performance is improved without degrading initial efficiency of a non-aqueous electrolyte secondary battery that includes a positive electrode, a negative electrode, a non-aqueous electrolyte containing a solute and a solvent, the positive electrode including a positive electrode active material made of a lithium-containing transition metal oxide that contains lithium and cobalt and has a layered structure. The lithium-containing transition metal oxide is at least partially covered with a surface-treatment layer containing a phosphate compound represented by the chemical formula M1POk, where M1 is at least one element that can have a valency of 3 and k is an integer in a range of 2 to 4, and the lithium-containing transition metal oxide contains a group IVA element M2 and a group IIA element M3 of the periodic table.

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: In a non-aqueous electrolyte secondary battery having a positive electrode, a negative electrode, and a non-aqueous electrolyte solution containing a fluorinated ester as a solvent, battery safety is improved without degrading charge-discharge characteristics. A non-aqueous electrolyte solution for a secondary battery contains a fluorinated ester represented by the chemical formula CHF2COOR, where R is an alkyl group having 1 to 4 carbon atoms or a halogen-atom-substituted alkyl group having 1 to 4 carbon atoms. The fluorinated ester has a water content of 30 ppm or less. The solvent additionally contains a cyclic carbonic ester having an unsaturated C?C bond.

Abstract: A nonaqueous electrolyte for a secondary battery is disclosed which contains at least 10% by volume of methyl difluoroacetate, based on a total volume of a solvent. The nonaqueous electrolyte uses, as a mixed solute, at least one A electrolyte salt selected from LiPF6 and LiBF4 and at least one B electrolyte salt selected from LiN(ClF2l+1SO2)(CmF2m+1SO2) (wherein l and m independently indicate an integer of at least 0) and LiC(CpF2p+1SO2)(CqF2q+1SO2)(CrF2r+1SO2) (wherein p, q and r independently indicate an integer of at least 0).

Abstract: A nonaqueous electrolyte secondary battery including a positive electrode 2 containing a positive electrode active material comprising a lithium-transition metal oxide having a layered structure, a negative electrode 1 and a nonaqueous electrolyte, wherein a surface treatment layer containing a compound represented by the chemical formula MlPmOn (wherein M is at least one element which can have a valence of 2, and l, m and n are integers in a range satisfying 21+5m=2n) is formed on at least a part of the surface of the positive electrode active material.

Abstract: A positive electrode active material for a nonaqueous electrolyte secondary battery comprising a lithium-transition metal oxide having a layered structure and containing at least cobalt as a transition metal, wherein at least part of the surface of the lithium-transition metal oxide is coated by a treatment layer comprising low-temperature phase lithium cobalt oxide.

Abstract: Charge-discharge characteristics are improved in a non-aqueous electrolyte secondary battery including a positive electrode, a negative electrode, and a non-aqueous electrolyte containing a phosphoric ester compound as a solvent. In a non-aqueous electrolyte for secondary batteries containing a phosphoric ester compound, a lithium salt having an oxalato complex as an anion is contained as a solute. Preferably, the non-aqueous electrolyte contains lithium bis(oxalato)borate at a concentration of 0.01 to 0.2 mol/L with respect to the solvent, and more preferably, the non-aqueous electrolyte also contains vinylene carbonate.