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 objective of the present invention is to prevent deterioration and expanding of anode active material and to improve charge-discharge cycle characteristics in a non-aqueous electrolyte secondary battery comprising an anode of which current collector has thereon a thin layer of an anode active material containing a metal. To solve this problem, in a non-aqueous electrolyte secondary battery wherein a thin layer of anode active material containing a metal which absorbs and discharges lithium is formed on a current collector and the thin layer of the anode active material is divided into columns by a gap formed along the thickness thereof, a compound represented by the following formula is contained in the non-aqueous electrolyte. A-N?C?O In the above formula, A represents an element or a group other than hydrogen.

Abstract: Disclosed is a nonaqueous electrolyte secondary battery which has a negative electrode containing silicon as a negative active material, a positive electrode containing a positive active material, a nonaqueous electrolyte and a separator. Characteristically, an additive which retards oxidation of silicon during operation of the battery is contained either in an interior or surface portion of the positive electrode, in an interior or surface portion of the negative electrode, or in an interior or surface portion of the separator.

Abstract: The objective of the present invention is to prevent deterioration and expanding of anode active material and to improve charge-discharge cycle characteristics in a non-aqueous electrolyte secondary battery comprising an anode of which current collector has thereon a thin layer of an anode active material containing a metal. To solve this problem, in a non-aqueous electrolyte secondary battery wherein a thin layer of anode active material containing a metal which absorbs and discharges lithium is formed on a current collector and the thin layer of the anode active material is divided into columns by a gap formed along the thickness thereof, a compound represented by the following formula is contained in the non-aqueous electrolyte. A-N?C?O In the above formula, A represents an element or a group other than hydrogen.

Abstract: The objective of the present invention is to prevent deterioration and expanding of anode active material and to improve charge-discharge cycle characteristics in a non-aqueous electrolyte secondary battery comprising an anode of which current collector has thereon a thin layer of an anode active material containing a metal. To solve this problem, in a non-aqueous electrolyte secondary battery wherein a thin layer of anode active material containing a metal which absorbs and discharges lithium is formed on a current collector and the thin layer of the anode active material is divided into columns by a gap formed along the thickness thereof, a compound represented by the following formula is contained in the non-aqueous electrolyte. A-N?C?O In the above formula, A represents an element or a group other than hydrogen.

Abstract: Disclosed is a nonaqueous electrolyte secondary battery which has a negative electrode containing silicon as a negative active material, a positive electrode containing a positive active material, a nonaqueous electrolyte and a separator. Characteristically, an additive which retards oxidation of silicon during operation of the battery is contained either in an interior or surface portion of the positive electrode, or in an interior or surface portion of the negative electrode, or in an interior or surface portion of the separator.

Abstract: Disclosed is a nonaqueous electrolyte secondary battery which has a negative electrode containing silicon as a negative active material, a positive electrode containing a positive active material, a nonaqueous electrolyte and a separator. Characteristically, an additive which retards oxidation of silicon during operation of the battery is contained either in an interior or surface portion of the positive electrode, or in an interior or surface portion of the negative electrode, or in an interior or surface portion of the separator.

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 objective of the present invention is to prevent deterioration and expanding of anode active material and to improve charge-discharge cycle characteristics in a non-aqueous electrolyte secondary battery comprising an anode of which current collector has thereon a thin layer of an anode active material containing a metal. To solve this problem, in a non-aqueous electrolyte secondary battery wherein a thin layer of anode active material containing a metal which absorbs and discharges lithium is formed on a current collector and the thin layer of the anode active material is divided into columns by a gap formed along the thickness thereof, a compound represented by the following formula is contained in the non-aqueous electrolyte. A-N?C?O In the above formula, A represents an element or a group other than hydrogen.

Abstract: A nonaqueous electrolyte secondary battery is obtained in which a potential of a positive-electrode active material in a fully charged condition is 4.4-4.6 V versus metallic lithium and an Li content of the positive-electrode active material at the potential does not exceed 40% of an initial Li content, and which can show improved cycle characteristics and charge-discharge characteristics. The nonaqueous electrolyte secondary battery includes a positive electrode containing a positive-electrode active material, a negative electrode containing a negative-electrode active material, and a nonaqueous electrolyte, wherein a potential of the positive electrode active material in a fully charged condition is 4.4-4.

Abstract: A lithium secondary battery includes: a plurality of sheets of a positive electrode; at least one sheet of a negative electrode; a separator disposed between each of the positive electrode sheets and the negative electrode sheet; an electrode assembly (20) including the positive electrode, the negative electrode, and the separators; a battery case for accommodating the electrode assembly; and positive electrode current collector tabs (1), attached to individual sheets of the positive electrode, for connecting the sheets of the positive electrode to a positive electrode terminal portion of the battery case. The electrode assembly (20) is formed so that the plurality of sheets of positive electrode and the at least one sheet of the negative electrode are stacked with the separators interposed therebetween. In the electrode assembly in which the electrodes are stacked, the positive electrode current collector tabs are disposed staggered at a plurality of locations.

Abstract: A non-aqueous electrolyte secondary battery using silicon as negative electrode active material and containing carbon dioxide in a non-aqueous electrolyte is provided that minimizes gas generation during storage in a charged state and improves charge-discharge cycle performance. The non-aqueous electrolyte secondary battery is provided with a negative electrode containing silicon as a negative electrode active material, a positive electrode, and a non-aqueous electrolyte containing electrolyte salts and a solvent. The non-aqueous electrolyte contains carbon dioxide, and the electrolyte salts include LiBF4 and another electrolyte salt that is less consumed relative to the LiBF4 during charge-discharge cycling.

Abstract: A non-aqueous electrolyte secondary battery using silicon as negative electrode active material and containing fluoroethylene carbonate in a non-aqueous electrolyte is provided that minimizes gas generation during storage in a charged state and improves charge-discharge cycle performance. The non-aqueous electrolyte secondary battery is provided with a negative electrode containing silicon as a negative electrode active material, a positive electrode, and a non-aqueous electrolyte containing electrolyte salts and a solvent. The non-aqueous electrolyte contains fluoroethylene carbonate, and the electrolyte salts include LiBF4 and another electrolyte salt that is less consumed relative to LiBF4 during charge-discharge cycling.

Abstract: To improve cycle characteristics in a non-aqueous electrolyte secondary battery containing silicon as a negative electrode active material. A non-aqueous electrolyte secondary battery comprising a negative electrode made of a negative electrode active material containing silicon, a positive electrode, and a non-aqueous electrolyte containing an electrolyte salt and a solvent, wherein a first electrolyte salt containing boron and fluorine and a second electrolyte salt having a decomposition rate on the surface of the negative electrode during charging and discharging, which is lower than that of the first electrolyte salt, are used as the electrolyte salt.

Abstract: Disclosed is a nonaqueous electrolyte secondary battery which has a negative electrode containing silicon as a negative active material, a positive electrode containing a positive active material, a nonaqueous electrolyte and a separator. Characteristically, an additive which retards oxidation of silicon during operation of the battery is contained either in an interior or surface portion of the positive electrode, or in an interior or surface portion of the negative electrode, or in an interior or surface portion of the separator.

Abstract: In a non-aqueous secondary cell having a positive electrode, a negative electrode, a nonaqueous electrolyte, a separator interposed between the positive electrode and the negative electrode, the positive electrode having a positive electrode active material including a chemical compound capable of reversibly intercalating lithium and the negative electrode having a negative electrode active material including a material capable of reversibly intercalating lithium, the separator has through holes formed therein for passing lithium dendrites therethrough.

Abstract: In a non-aqueous secondary cell having a positive electrode, a negative electrode, a nonaqueous electrolyte, a separator interposed between the positive electrode and the negative electrode, the positive electrode having a positive electrode active material including a chemical compound capable of reversibly intercalating lithium and the negative electrode having a negative electrode active material including a material capable of reversibly intercalating lithium, the separator has through holes formed therein for passing lithium dendrites therethrough.