Abstract: A secondary battery includes a positive electrode, a negative electrode, and a separator. The separator is interposed between the positive electrode and the negative electrode. The separator includes a porous layer, a first adhesion layer, and a second adhesion layer. The first adhesion layer is provided between the porous layer and the positive electrode, and is adhered to the positive electrode. The second adhesion layer is provided between the porous layer and the negative electrode, and is adhered to the negative electrode. After the separator is heated at a heating temperature of 130° C.±5° C. for a heating time of one hour, an adhesion strength of the first adhesion layer with respect to the positive electrode is larger than an adhesion strength of the first adhesion layer with respect to the porous layer, and an adhesion strength of the second adhesion layer with respect to the negative electrode is larger than an adhesion strength of the second adhesion layer with respect to the porous layer.

Abstract: Provided is a negative electrode for a lithium ion secondary battery including: a negative electrode current collector; and a negative electrode active material for a lithium ion secondary battery which is disposed on the negative electrode current collector and contains a carbon material and an aqueous binder. The carbon material is a graphite particle having a covering layer containing amorphous carbon by 5 wt % or less relative to a total weight of the carbon material.

Abstract: A negative electrode for a lithium ion secondary battery includes: a negative electrode current collector (11); and a negative electrode active material for a lithium ion secondary battery, which is disposed on the negative electrode current collector and contains a carbon material and an aqueous binder. The carbon material is a graphite particle having a covering layer containing amorphous carbon by 5 wt % or less relative to a total weight of the carbon material.

Abstract: An organic acid included in a nonaqueous electrolyte solution of a secondary battery is reduced. During preparation of a film-covered battery 1, the nonaqueous electrolyte solution is injected into an covering 5 of the film-covered battery 1 having an electrode including: the electrode active material, the binder, and the organic acid, the organic acid in the nonaqueous electrolyte solution is decomposed by electrical charging of a battery until a voltage level is equal to or above a decomposition voltage of the organic acid, and the gas that is produced by decomposition is degassed from the cut portion 6 of the covering 5.

Abstract: A negative electrode for a lithium ion secondary battery includes: a negative electrode current collector (11); and a negative electrode active material for a lithium ion secondary battery, which is disposed on the negative electrode current collector and contains a carbon material and an aqueous binder. The carbon material is a graphite particle having a covering layer containing amorphous carbon by 5 wt % or less relative to a total weight of the carbon material.

Abstract: Provided is a negative electrode for a lithium ion secondary battery including: a negative electrode current collector; and a negative electrode active material for a lithium ion secondary battery which is disposed on the negative electrode current collector and contains a carbon material and an aqueous binder.

Abstract: A lithium ion secondary battery electrode according to the present invention includes (A) a non-fluorinated polymer; (B) an active material; (C) a thickener; and (D) a conductive auxiliary agent. An elution ratio of (A) the non-fluorinated polymer in an electrolytic solution solvent at 60° C. is equal to or less than 1.0 mass %, and a swelling ratio of (A) the non-fluorinated polymer in the electrolytic solution solvent at 60° C. is equal to or more than 10 mass % and equal to or less than 50 mass %.

Abstract: A negative electrode for a lithium ion secondary battery according to the present invention includes a negative electrode active material and a binder, in which the negative electrode active material satisfies the following requirements (A), (B), and (C): (A) graphite powder is used as a core material, and at least a part of a surface of the graphite powder is coated with a carbon material having lower crystallinity than the graphite powder; (B) a specific surface area measured using a nitrogen adsorption BET method is more than or equal to 0.8 m2/g and less than or equal to 5.3 m2/g; and (C) an amount of dibutyl phthalate absorption measured according to JIS K 6217-4 is more than or equal to 32 cm3/100 g and less than or equal to 45 cm3/100 g.

Abstract: An organic acid included in a nonaqueous electrolyte solution of a secondary battery is reduced. During preparation of a film-covered battery 1, the nonaqueous electrolyte solution is injected into an covering 5 of the film-covered battery 1 having an electrode including: the electrode active material, the binder, and the organic acid, the organic acid in the nonaqueous electrolyte solution is decomposed by electrical charging of a battery until a voltage level is equal to or above a decomposition voltage of the organic acid, and the gas that is produced by decomposition is degassed from the cut portion 6 of the covering 5.

Abstract: A lithium ion secondary battery electrode according to the present invention includes (A) a non-fluorinated polymer; (B) an active material; (C) a thickener; and (D) a conductive auxiliary agent. An elution ratio of (A) the non-fluorinated polymer in an electrolytic solution solvent at 60° C. is equal to or less than 1.0 mass %, and a swelling ratio of (A) the non-fluorinated polymer in the electrolytic solution solvent at 60° C. is equal to or more than 10 mass % and equal to or less than 50 mass %.

Abstract: The object of an exemplary embodiment of the invention is to provide a lithium secondary battery which has high energy density by containing a positive electrode active substance operating at a potential of 4.5 V or higher with respect to lithium and which has excellent cycle property. An exemplary embodiment of the invention is an lithium secondary battery, which comprises a positive electrode comprising a positive electrode active substance and an electrolyte liquid comprising a nonaqueous electrolyte solvent; wherein the positive electrode active substance operates at a potential of 4.5 V or higher with respect to lithium; and wherein the nonaqueous electrolyte solvent comprises a fluorine-containing phosphate represented by a prescribed formula.

Abstract: A nonaqueous electrolyte secondary battery comprising positive and negative electrodes capable of absorbing and desorbing lithium ions; a nonaqueous electrolytic solution; and a separator provided between the positive electrode and the negative electrode. The negative electrode comprises a negative electrode active material layer containing at least a styrene polymer as a binder in a content of 0.3 to 8.0 mass % based on the total mass of the negative electrode active material layer. The nonaqueous electrolytic solution contains at least a cyclic sulfonic acid ester including at least two sulfonyl groups in a content of 0.002 to 5.0 mass % based on the total mass of the nonaqueous electrolytic solution.