A disclosed method is a method of manufacturing a battery including a wound electrode assembly in which a first separator, a negative electrode plate, a second separator, and a positive electrode plate are wound together. The method includes steps of winding the first separator, the negative electrode plate, the second separator, and the positive electrode plate onto a winding core, to prepare a wound electrode assembly, and removing the wound electrode assembly from the winding core. The winding core includes a first component and a second component. In the step of removing the wound electrode assembly from the winding core, at least one of the first component and the second component moves in a direction in which a distance between the first component and the second component decrease so that a diameter of the winding core decreases. Thereafter, the wound electrode assembly is removed from the winding core.

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 method of manufacturing a battery is disclosed. The method includes the steps of (A) suction-attaching the first separator to a winding core, (B) winding the first separator on the winding core, and (C) removing the wound electrode assembly from the winding core. The winding core includes a first group of holes and a second group of holes each formed in its outer circumferential surface. In step (A), suction is applied to the first separator through at least one of the first group of holes and the second group of holes, to suction-attach the first separator to the winding core. The first group of holes and the second group of holes are configured to be controllable so as to cause suction and gas discharge independently from each other.

A method of manufacturing a battery is disclosed. The method includes the steps of (A) suction-attaching the first separator to a winding core, (B) winding the first separator on the winding core, and (C) removing the wound electrode assembly from the winding core. The winding core includes a first group of holes and a second group of holes each formed in its outer circumferential surface. In step (A), suction is applied to the first separator through at least one of the first group of holes and the second group of holes, to suction-attach the first separator to the winding core. The first group of holes and the second group of holes are configured to be controllable so as to cause suction and gas discharge independently from each other.

A method of manufacturing method a battery includes the following steps. Step (A): causing, with the first separator and the second separator being stacked on each other, the first separator and the second separator to be suction-attached to a winding core and to be pressed against the winding core with a jig including a plurality of protrusions formed on a surface of the jig. Step (B): winding the first separator and the second separator onto the winding core.

A method of manufacturing method a battery includes the following steps. Step (A): causing, with the first separator and the second separator being stacked on each other, the first separator and the second separator to be suction-attached to a winding core and to be pressed against the winding core with a jig including a plurality of protrusions formed on a surface of the jig. Step (B): winding the first separator and the second separator onto the winding core.

An electrode for batteries that does not include a metal-film-type current collector is disclosed herein. In some embodiments, the electrode comprises a composite having a core-shell structure including a core having an electrode active material, and a metal material coated on or doped in the surface of the core. A secondary battery having the electrode has increased capacity and energy density and exhibits improved lifespan characteristics.

A secondary battery includes a battery element including a positive electrode, a negative electrode, and an electrolytic solution, a housing member configured to accommodate the battery element, and a safety valve mechanism attached to the housing member. The safety valve mechanism includes a valve member including an opening valve portion configured to be opened; and an opening member including a plurality of opening portions radially arranged in a region opposed to the opening valve portion from a center of the region as a base point, and a plurality of protrusion portions radially arranged in a region outside the plurality of opening portions from the center and the plurality of protrusion portions protrude toward the plurality of opening portions. A number of the opening portions and a number of the protrusion portions are equal to each other, and each of the plurality of opening portions and each of the plurality of protrusion portions are opposed to each other in a direction toward the center.

A cylindrical secondary battery configured to have a structure to which an adhesion unit, including an adhesive material, a conductive material, and a gas-generating material, is provided. The adhesion unit is configured to couple a cap assembly, which functions as a positive electrode terminal of the cylindrical secondary battery, and a positive electrode tab of a jelly-roll type electrode assembly to each other.