A sealing assembly for sealing a through hole, and a method and device for preparing a battery cell are provided. The sealing assembly comprises: a sealing sleeve provided in the through hole and having a cavity and an opening that is in communication with the cavity; an elastic sleeve tube provided in the cavity and having a first mounting hole that extends in an axial direction of the through hole; and a central rod, which is provided in the first mounting hole and is in threaded connection with the elastic sleeve tube to enable the elastic sleeve tube to expand in a radial direction of the through hole to press the sealing sleeve and form, on an outer wall of the elastic sleeve tube, a raised portion that rivets the sealing sleeve to the through hole. The sealing assembly for sealing the through hole, and the method and device for preparing the battery cell according to the embodiments of the present application can improve the sealing performance on the through hole of the battery cell.

A secondary battery includes: an electrode assembly including a first electrode plate, a second electrode plate, and a separator; a can having a closed upper surface with a rivet opening therein and an open lower surface to accommodate the electrode assembly, the can being electrically connected to the first electrode plate; a rivet terminal in the rivet opening and electrically connected to the second electrode plate; a gasket between the can and the rivet terminal; and a cap plate sealing the lower surface of the can.

A pouch-type secondary battery includes an electrode assembly including a first electrode plate, a separator, and a second electrode plate; and a pouch film in which the electrode assembly is accommodated, wherein the pouch film includes a first side sealing portion from which a negative electrode lead connected to the electrode assembly protrudes, a second side sealing portion from which a positive electrode lead connected to the electrode assembly protrudes, and an upper sealing portion having both end portions connected to the first and second side sealing portions, and the pouch film includes a folded portion disposed on an end of the first side sealing portion and an end of the second side sealing portion, and folded toward a bottom portion of the pouch film, wherein the folded portion is folded in one direction.

A pouch-type secondary battery includes an electrode assembly including a first electrode plate, a separator, and a second electrode plate; and a pouch film in which the electrode assembly is accommodated, wherein the pouch film includes a first side sealing portion from which a negative electrode lead connected to the electrode assembly protrudes, a second side sealing portion from which a positive electrode lead connected to the electrode assembly protrudes, and an upper sealing portion having both end portions connected to the first and second side sealing portions, and the pouch film includes a folded portion disposed on an end of the first side sealing portion and an end of the second side sealing portion, and folded toward a bottom portion of the pouch film, wherein the folded portion is folded in one direction.

A secondary battery includes a battery can and a cover member. The battery can has a container-shaped structure and contains a battery device inside. The cover member is attached to an open surface of the battery can via a gasket. The cover member includes stainless steel coated with nickel plating. The nickel plating has a crystal structure in which a proportion of columnar crystals is greater than or equal to 80%.

A cylindrical secondary battery includes: a cylindrical can having a circular bottom portion, a side portion extending from the bottom portion, a beading part concavely formed inwardly at one end of the side portion, and a crimping part formed by bending a distal end of the side portion; an electrode assembly in the can; and a cap assembly sealing the can. The cap assembly includes a gasket for insulation from the can, and an upper portion of the gasket in a direction away from the electrode assembly has a smaller thickness than a lower portion of the gasket.

A battery including a battery body and a flange portion; the battery body includes a first side face protruding from a surface of the battery body; the flange portion is arranged outside the battery body and includes a protrusion segment connected to the battery body, the protrusion segment protruding away from the battery body.

A battery including a battery body and a flange portion; the battery body includes a first side face protruding from a surface of the battery body; the flange portion is arranged outside the battery body and includes a protrusion segment connected to the battery body, the protrusion segment protruding away from the battery body.

A sealed battery, which is an exemplary embodiment, comprises a battery case including a bottomed cylindrical outer can and a sealing body that closes an opening of the outer can, a gasket disposed between the outer can and the sealing body, and an electrode body including an electrode and housed in the battery case. The sealing body includes a metal plate, and the metal plate has a thin portion formed in an annular shape, a valve portion having a convex shape inside the battery case, and an annular portion to which the electrode lead is connected. The gasket is provided with an elastically deformable portion that abuts against the inner surface of the valve portion and urges the valve portion to the outside of the battery case.

A sealed battery, which is an exemplary embodiment, comprises a battery case including a bottomed cylindrical outer can and a sealing body that closes an opening of the outer can, a gasket disposed between the outer can and the sealing body, and an electrode body including an electrode and housed in the battery case. The sealing body includes a metal plate, and the metal plate has a thin portion formed in an annular shape, a valve portion having a convex shape inside the battery case, and an annular portion to which the electrode lead is connected. The gasket is provided with an elastically deformable portion that abuts against the inner surface of the valve portion and urges the valve portion to the outside of the battery case.