Abstract: A battery device comprises a nonaqueous electrolyte secondary battery provided with an electric power generating element and a pressing member which presses the electric power generating element in the stacking direction. The electric power generating element comprises: a positive electrode with a positive electrode active material layer of a positive electrode active material on the surface of a positive electrode collector; a negative electrode with a negative electrode active material layer of a negative electrode active material on the surface of a negative electrode collector; and a separator which holds an electrolyte solution. This battery device satisfies (1) 0.1<(T1?T2)/T1×100<5, where T1 is the thickness of the thickest portion of the electric power generating element in the stacking direction, and T2 is the thickness of the thinnest portion of the of the electric power generating element in the stacking direction.

Abstract: A predoping method for a negative electrode active material to dope the negative electrode active material with lithium ions. The predoping method for a negative electrode active material includes: a predoping process and a post-doping modification process. In the predoping process, the negative electrode active material is doped with lithium ions, to thereby reduce a potential of the negative electrode active material relative to lithium metal. In the post-doping modification process, after the predoping process, reaction is caused between a reactive compound that is reactive with lithium ions and lithium ions doped into the negative electrode active material, to thereby increase the potential of the negative electrode active material relative to lithium metal. The potential of the negative electrode active material relative to lithium metal is 0.8 V or more at completion of the post-doping modification process.

Abstract: Provided is a technique capable of further improving the cycle characteristics in a negative electrode for a non-aqueous electrolyte secondary battery in which a silicon-based negative electrode active material and a carbon-based negative electrode active material are used in combination as a negative electrode active material, and constituent components of the electrode are not bound to each other via a binder. The negative electrode for a non-aqueous electrolyte secondary battery according to the present invention has a configuration in which a negative electrode active material layer containing a negative electrode active material is formed on a surface of a current collector. The negative electrode active material contains composite secondary particles in which silicon-based negative electrode active material particles and carbon-based negative electrode active material particles are bound to each other via a binder.

Abstract: A battery device comprises a nonaqueous electrolyte secondary battery provided with an electric power generating element and a pressing member which presses the electric power generating element in the stacking direction. The electric power generating element comprises: a positive electrode with a positive electrode active material layer of a positive electrode active material on the surface of a positive electrode collector; a negative electrode with a negative electrode active material layer of a negative electrode active material on the surface of a negative electrode collector; and a separator which holds an electrolyte solution. This battery device satisfies (1) 0.1<(T1?T2)/T1×100<5, where T1 is the thickness of the thickest portion of the electric power generating element in the stacking direction, and T2 is the thickness of the thinnest portion of the of the electric power generating element in the stacking direction.

Abstract: A non-aqueous electrolyte secondary battery has a power generating element that includes a positive electrode in which a positive electrode active material layer including a positive electrode active material is formed on a surface of a positive electrode current collector, a negative electrode in which a negative electrode active material layer including a negative electrode active material is formed on a surface of a negative electrode current collector, and a separator impregnated with an electrolyte solution. The negative electrode active material includes a Si material that contains silicon and is capable of insertion and removal of lithium ions. The electrolyte solution contains lithium bis(fluorosulfonyl)imide (LiFSI) and an inorganic lithium salt other than the LiFSI, and has a feature that a ratio of a concentration (mol/L) of the LiFSI with respect to a concentration (mol/L) of the inorganic lithium salt (LiFSI/inorganic lithium salt) in the electrolyte solution is 1 or less.

Abstract: A predoping method for a negative electrode active material to dope the negative electrode active material with lithium ions using an electrolyte solution that includes lithium ions. The electrolyte solution includes at least one type of additive having a reduction potential higher than a reduction potential of a solvent contained in the electrolyte solution.

Abstract: To provide a non-aqueous electrolyte secondary battery negative electrode material that can be produced even without performing a heat treatment at a high temperature such as 2,000° C. or higher and can have the discharge capacity further increased. The non-aqueous electrolyte secondary battery negative electrode material according to the invention has a core portion including carbonaceous negative electrode active material particles; and a shell portion including a polyimide and silicon-based negative electrode active material particles and/or tin-based negative electrode active material particles. There is a feature that the value of the ratio of the volume average particle size (D50) of the silicon-based negative electrode active material particles and/or tin-based negative electrode active material particles with respect to the volume average particle size (D50) of the carbonaceous negative electrode active material particles is 0.001 to 0.

Abstract: A predoping method for a negative electrode active material to dope the negative electrode active material with lithium ions. The predoping method for a negative electrode active material includes: a predoping process and a post-doping modification process. In the predoping process, the negative electrode active material is doped with lithium ions, to thereby reduce a potential of the negative electrode active material relative to lithium metal. In the post-doping modification process, after the predoping process, reaction is caused between a reactive compound that is reactive with lithium ions and lithium ions doped into the negative electrode active material, to thereby increase the potential of the negative electrode active material relative to lithium metal. The potential of the negative electrode active material relative to lithium metal is 0.8 V or more at completion of the post-doping modification process.

Abstract: To provide an electrode for a lithium ion secondary battery capable of enhancing a charge and discharge cycle durability of an electrode that uses a resin current collector. An electrode for a lithium ion secondary battery provided with a resin current collector including a polyolefin resin matrix and a conductive filler A, and an electrode active material layer provided on the resin current collector, in which a crosslinked resin thin-film layer, which contains an Ni filler as a conductive filler B that does not alloy with Li and which has impermeability to the electrolyte solution, is arranged between the resin current collector and a negative electrode active material layer.

Abstract: To provide a non-aqueous electrolyte secondary battery negative electrode material that can be produced even without performing a heat treatment at a high temperature such as 2,000° C. or higher and can have the discharge capacity further increased. The non-aqueous electrolyte secondary battery negative electrode material according to the invention has a core portion including carbonaceous negative electrode active material particles; and a shell portion including a polyimide and silicon-based negative electrode active material particles and/or tin-based negative electrode active material particles. There is a feature that the value of the ratio of the volume average particle size (D50) of the silicon-based negative electrode active material particles and/or tin-based negative electrode active material particles with respect to the volume average particle size (D50) of the carbonaceous negative electrode active material particles is 0.001 to 0.

Abstract: To provide a negative electrode for a lithium ion battery which is excellent in energy density and cycle characteristics and has a small volume change at the time of charging. Provided is a negative electrode for a lithium ion battery comprising a negative electrode active material layer, in which the negative electrode active material layer is formed from a non-bound body of a mixture containing silicon and/or silicon compound particles and carbon-based negative electrode active material particles, a volume average particle size of the silicon and/or silicon compound particles is 0.01 to 10 ?m, a volume average particle size of the carbon-based negative electrode active material particles is 15 to 50 ?m, and a mass mixing ratio of the total of the silicon and silicon compound particles and the carbon-based negative electrode active material particles contained in the mixture is 5:95 to 45:55.

Abstract: To provide an electrode for a lithium ion secondary battery capable of enhancing a charge and discharge cycle durability of an electrode that uses a resin current collector. An electrode for a lithium ion secondary battery provided with a resin current collector including a polyolefin resin matrix and a conductive filler A, and an electrode active material layer provided on the resin current collector, in which a crosslinked resin thin-film layer, which contains an Ni filler as a conductive filler B that does not alloy with Li and which has impermeability to the electrolyte solution, is arranged between the resin current collector and a negative electrode active material layer.