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 is disclosed. The method includes step (A) of suction-attaching the first separator to a winding core, and step (B) of winding the first separator on the winding core. The winding core includes a plurality of suction holes for suction-attaching the first separator. When the outer circumference of the winding core is divided into four equal parts and the four equal parts are defined respectively as first to fourth regions starting from a position that faces a starting end of winding of the first separator, greater than or equal to 80%, by aperture area ratio, of the suction holes are formed in the first region.

An electrode sheet includes a current collector and a first active material layer on a first surface of the current collector. The first active material layer includes a main portion and a first buffer portion. The main portion includes a first inner surface and an outer surface. The first inner surface is attached to the current collector, and the outer surface is parallel to the first inner surface. The first active material layer has a height that is a vertical distance from the outer surface to the first inner surface. The first buffer portion includes a second inner surface, a buffer surface, and an inner wall surface defining a first groove. A first end of the buffer surface is connected to the outer surface, a second end of the buffer surface is connected to the inner wall surface. The inner wall surface is shorter than the first active material layer.

Provided is a lithium secondary battery comprising: a positive electrode including a positive electrode active material; a negative electrode including a negative electrode active material; and a first functional layer between the positive electrode and the negative electrode, wherein the first functional layer includes plate-like polyolefin particles having an average diameter of 1 μm to 8 μm, and the positive electrode includes a positive electrode active material layer including a positive electrode active material and a flame retardant, or has a stacked structure including a positive electrode active material layer and a second functional layer including a flame retardant.

An electrode assembly having a positive electrode; a negative electrode; and a separator interposed between the positive electrode and the negative electrode is provided. The positive electrode includes a positive electrode active material layer located on a positive electrode current collector, and the negative electrode includes a negative electrode active material layer located on a negative electrode current collector. A non-coated part is located at an edge of the negative electrode current collector. A disconnection preventing layer is located at the negative electrode current collector. The disconnection preventing layer extends from an external side of the non-coated part and is bent to overlap a portion of the non-coated part.

(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 disclosed method of manufacturing a battery includes the steps of: (A) suction-attaching a first separator and a second separator to a winding core, with the first separator and the second separator being stacked on each other; and (B) winding the first separator and the separator around the winding core. Each of the first separator and the second separator includes a porous substrate layer made of resin, and at least one surface layer formed on at least one surface of the substrate layer.

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 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.

Apparatus for winding at least one strip of material for the production of electrical energy storage devices, comprising: a rotatable winding core, configured to grip the strip and actuatable to carry it in rotation and thus form a winding; a feed unit to feed the strip of material; and a handling device configured to move the winding core at least between a winding station, at which the winding core is configured to receive the strip in feeding, grip it and wind it about the rotation axis, and a second station; wherein the handling device is configured to move the winding core from the winding station to the second station during the winding.

A lithium-sulfur battery includes a casing, a top lid circumferentially welded to the casing, a negative contact surface positioned opposite the top lid, a positive terminal disposed within the casing, welded to the top lid, and configured as a mandrel, a glass insulator circumferentially wound around the mandrel, and a jelly roll including at least an anode and a cathode wound around the mandrel. The jelly roll may also include a top surface not in contact with the top lid, a bottom surface partially in contact with the negative contact surface, and partially in contact with a plurality of non-hollow carbonaceous spherical particles disposed between the bottom surface of the jelly roll and the negative contact surface. At least some of the non-hollow carbonaceous spherical particles may provide one or more electrically-conductive pathways between the bottom surface and the negative contact surface.