(A): Winding a first separator, a second separator, a positive electrode plate, and a negative electrode plate onto a winding core disposed at a first position. (B): Moving the winding core away from the first position and disposing another winding core at the first position. (C): Cutting the first separator and the second separator wound on the winding core that is moved away from the first position in (B) at a location on or near the other winding core disposed at the first position in (B), with the first separator and the second separator being stacked and retained on an outer circumferential surface of the other winding core. (D): Winding the first separator and the second separator onto the winding core that is moved away from the first position in (B) up to a cut edge portion at which the first separator and the second separator are cut in (C).

(A): Winding a first separator, a second separator, a positive electrode plate, and a negative electrode plate onto a winding core disposed at a first position. (B): Moving the winding core away from the first position and disposing another winding core at the first position. (C): Cutting the first separator and the second separator wound on the winding core that is moved away from the first position in (B) at a location on or near the other winding core disposed at the first position in (B), with the first separator and the second separator being stacked and retained on an outer circumferential surface of the other winding core. (D): Winding the first separator and the second separator onto the winding core that is moved away from the first position in (B) up to a cut edge portion at which the first separator and the second separator are cut in (C).

A method of manufacturing a battery includes the step of: (A) winding a first separator, a second separator, a positive electrode plate, and a negative electrode plate onto a winding core disposed at a first position; (B) moving the winding core away from the first position and disposing another winding core at the first position; (C) cutting the first separator and the second separator wound on the winding core moved away from the first position, at a groove provided in an outer circumferential surface of the other winding core along the axial direction of the other winding core, with the first separator and the second separator being retained on the outer circumferential surface of the other winding core disposed at the first position; and (D) winding the first separator and the second separator onto the winding core moved away from the first position up to a cut edge portion.

A method of manufacturing a battery includes the step of: (A) winding a first separator, a second separator, a positive electrode plate, and a negative electrode plate onto a winding core disposed at a first position; (B) moving the winding core away from the first position and disposing another winding core at the first position; (C) cutting the first separator and the second separator wound on the winding core moved away from the first position, at a groove provided in an outer circumferential surface of the other winding core along the axial direction of the other winding core, with the first separator and the second separator being retained on the outer circumferential surface of the other winding core disposed at the first position; and (D) winding the first separator and the second separator onto the winding core moved away from the first position up to a cut edge portion.

A battery is provided in which an electrode tab group is hardly damaged. In the herein disclosed battery, an electrode body includes an electrode body main body part, a positive electrode tab group protruding from a first end part, and a negative electrode tab group protruding from a second end part. The positive electrode tab group and the negative electrode tab group are folded and bent to make tip ends of electrode tabs respectively configuring these tab groups be arranged along a second side wall of the battery case. A portion of the folded and bent electrode tab is joined to the electrical collector body of the same pole. The battery includes a spacer between the electrode body main body part and the second side wall, and the spacer is to regulate movement of the electrode body.

A battery is provided in which an electrode tab group is hardly damaged. In the herein disclosed battery, an electrode body includes an electrode body main body part, a positive electrode tab group protruding from a first end part, and a negative electrode tab group protruding from a second end part. The positive electrode tab group and the negative electrode tab group are folded and bent to make tip ends of electrode tabs respectively configuring these tab groups be arranged along a second side wall of the battery case. A portion of the folded and bent electrode tab is joined to the electrical collector body of the same pole. The battery includes a spacer between the electrode body main body part and the second side wall, and the spacer is to regulate movement of the electrode body.

A battery includes: a core cell including a first surface and a second surface which are opposite each other and on which first and second electrodes are respectively located, and a lateral surface connecting the first and second surfaces; an insulating sheet arranged on the first surface of the core cell and in which a conduction hole facing the first electrode is defined; and an electrode plate arranged on the insulating sheet and electrically connected to the first electrode through the conduction hole.

The present invention efficiently avoids distortion at an edge and achieves a separator core which has strength. The present invention achieves: a separator core in which an outer cylindrical part has a linearly inclined face at an edge of an outer peripheral surface thereof; and a separator roll including the separator core and a separator for a nonaqueous electrolyte secondary battery wound around the separator core. The present invention provides a method of producing the separator roll.

A negative electrode comprises a negative electrode collector, a first negative electrode mixture layer that is provided on the surface of the negative electrode collector, and a second negative electrode mixture layer that faces the positive electrode; the first negative electrode mixture layer and the second negative electrode mixture layer contain graphite particles; the ratio of the void fraction (S2) among the graphite particles in the second negative electrode mixture layer to the void fraction (S1) among the graphite particles in the first negative electrode mixture layer, namely S2/S1 is from 1.1 to 2.0; the ratio of the packing density (D2) of the second negative electrode mixture layer to the packing density (D1) of the first negative electrode mixture layer, namely D2/D1 is from 0.9 to 1.1; and the separator has a thickness of 10 μm or less, while having a porosity of from 25% to 45%.

A negative electrode comprises a negative electrode collector, a first negative electrode mixture layer that is provided on the surface of the negative electrode collector, and a second negative electrode mixture layer that faces the positive electrode; the first negative electrode mixture layer and the second negative electrode mixture layer contain graphite particles; the ratio of the void fraction (S2) among the graphite particles in the second negative electrode mixture layer to the void fraction (S1) among the graphite particles in the first negative electrode mixture layer, namely S2/S1 is from 1.1 to 2.0; the ratio of the packing density (D2) of the second negative electrode mixture layer to the packing density (D1) of the first negative electrode mixture layer, namely D2/D1 is from 0.9 to 1.1; and the separator has a thickness of 10 μm or less, while having a porosity of from 25% to 45%.