A rechargeable battery includes an electrode assembly including a first electrode plate, a second electrode plate, and a separator between the first electrode plate and the second electrode plate, a can in which the electrode assembly is accommodated, the can including an opening at one side, the opening being hermetically sealed by a cap plate, and a top plate on the cap plate. The top plate includes a first welding unit and a second welding unit that are coupled to the cap plate, and a third welding unit that is between the first welding unit and the second welding unit. The first welding unit is connected to the cap plate and includes first through third welding points. The first through third welding points collectively forming a triangular shape.

Battery covers and methods for producing battery covers are described. One battery cover described herein includes a single sheet of material formed into a substantially rectangular box shape with an opening formed along one side, the rectangular box shape capable of being folded into a flattened shape for transportation and the material including a flexible laminate of at least one layer of synthetic fiber and a polymer film layer. The material has a thickness and other properties such that when the battery cover is unfolded, the material substantially maintains the rectangular box shape, and when the battery cover is folded into the flattened shape, the material maintains a spring force such that, unless restrained, the battery cover would unfold to the rectangular box shape.

A rechargeable battery includes an electrode assembly having first and second electrodes at opposite sides of a separator and wound about an axis; a first terminal coupled to the first electrode through a first tab; a second terminal coupled to the second electrode through a second tab; a case accommodating the electrode assembly and including first and second openings at its opposite ends; a first gasket between the first terminal and the first opening, the first gasket sealing the first opening and allowing the first terminal to protrude outside of the case; and a second gasket between the second terminal and the second opening, the second gasket sealing the second opening and allowing the second terminal to protrude outside of the case. The case may further include a fixing portion at its inner side that protrudes toward the electrode assembly.

A rechargeable battery includes a case; an electrode assembly accommodating the case; a cap plate sealing an opening of the case; terminals electrically coupled to the electrode assembly and penetrating the cap plate; terminal plates on the cap plate and coupled to a respective one of the terminals; and a connecting member including a sinuous body located between the cap plate and the terminal plate to electrically couple the cap plate and the terminal plate.

A flexible secondary battery includes: an electrode assembly including a first electrode layer, a second electrode layer, and a separator between the first electrode layer and the second electrode layer; a gasket having flexibility and surrounding edges of the electrode assembly; a first sealing sheet attached to a first surface of the gasket; and a second sealing sheet attached to a second surface of the gasket facing away from the first surface, wherein an uneven pattern is at a bendable area of the gasket.

A curved secondary battery may include a can having an opening, an electrode assembly accommodated in the can, and a cap plate coupled to the can. The cap plate may include a concave first side surface and a parallel convex second side surface, and a first surface and a second surface that connect the first and second side surfaces. The first surface may include a first groove extending along a lengthwise direction of the cap plate and positioned closer to the first side surface than to the second side surface.

Provided is a nonaqueous electrolyte secondary battery including a bottomed cylindrical positive electrode casing, and a negative electrode casing which is fixed to an opening of the positive electrode casing through a gasket. The opening of the positive electrode casing is caulked to the negative electrode casing side to seal an accommodation space. A caulking tip end in the opening of the positive electrode casing is disposed in an inward direction of the negative electrode casing than a tip end of the negative electrode casing. A diameter d of the nonaqueous electrolyte secondary battery is in a range of 4 mm to 12 mm, a height h1 of the nonaqueous electrolyte secondary battery is in a range of 1 mm to 3 mm, a side surface portion of the positive electrode casing is formed in a curved surface shape, a radius of curvature R is set in a range of 0.8 mm to 1.1 mm, and a height h2 of the positive electrode casing is in a range of 65% to 90% with respect to the height h1 of the nonaqueous electrolyte secondary battery.

The present application relates to a secondary battery head cover assembly, a secondary battery including the same and an assembling method thereof. The secondary battery head cover assembly includes a head cover and an insulation structure, the insulation structure includes a top connection sheet and two naked battery core insulation sheets, an electrode pole is provided on the head cover, and an electrode pole through hole, through which the electrode pole passes, is provided at a position on the top connection sheet corresponding to the electrode pole, the top connection sheet is located below the head cover and is fixed to the head cover. The secondary battery includes the secondary battery head cover assembly and the naked battery core, the naked battery core is located below the top connection sheet, and the two naked battery core insulation sheets wrap the side and bottom surfaces of the naked battery core.

A rechargeable battery according to an exemplary embodiments includes: an electrode assembly; a case configured to accommodate the electrode assembly and having an opening at one side thereof; and a cap assembly including: a cap plate configured to close and seal the opening of the case, the cap plate having a vent portion and defining a vent opening that is configured to discharge an internal gas generated inside the case to the outside of the case, the vent portion comprising: a vent plate configured to close and seal the vent opening; and a bending portion that is raised from the vent plate; and an electrode terminal at an upper portion of the cap plate and electrically connected to the electrode assembly.

A battery cover is disclosed. The battery cover has a lower battery cover and an upper battery cover. The upper battery cover is matable with the lower battery cover to form a labyrinth and a plurality of battery cover sides. The labyrinth has a plurality of labyrinth cell passageways between a plurality of cell openings and a plurality of mixing areas, and the labyrinth cell passageways extend above an acid level when tipped all directions onto the battery cover sides from an upright orientation.