Abstract: A secondary battery includes a unit cell including an electrode assembly provided with a tab bundle and having a round portion, and a cap member in the vicinity of the round portion of the electrode assembly. The cap member includes a pair of first surfaces which are parallel to an upper surface and a lower surface of the electrode assembly, a pair of second surfaces which are parallel to both side surfaces of the electrode assembly, one third surface which connects the pair of first surfaces and the pair of second surfaces, and a contact member provided in an internal space formed by the pair of first surfaces, the pair of second surfaces, and the one third surface and in contact with the round portion of the electrode assembly. The third surface is provided with a through hole through which the tab bundle passes.

Abstract: A secondary battery includes a unit cell including an electrode assembly provided with a tab bundle and having a round portion, and a cap member in the vicinity of the round portion of the electrode assembly. The cap member includes a pair of first surfaces which are parallel to an upper surface and a lower surface of the electrode assembly, a pair of second surfaces which are parallel to both side surfaces of the electrode assembly, one third surface which connects the pair of first surfaces and the pair of second surfaces, and a contact member provided in an internal space formed by the pair of first surfaces, the pair of second surfaces, and the one third surface and in contact with the round portion of the electrode assembly. The third surface is provided with a through hole through which the tab bundle passes.

Abstract: A method for estimating battery cell capacity may comprise deriving a discharge curve for each battery cell included in a module including a plurality of battery cells; deriving a charge curve for each battery cell included in the module; calculating an additional dischargeable capacity of a second battery cell based on a pattern of the discharge curve of a first battery cell; calculating an additional chargeable capacity of the second battery cell based on the transition of the charge curve of the first battery cell; and calculating a capacity of the second battery cell based on the additional dischargeable capacity and the additional chargeable capacity of the second battery cell.