Patent ID: 8980463
Filing Date: 2015-03-17
Classification: H01M,Y02E,Y02P

Abstract:
1. A secondary battery comprising: an electrode assembly in which a cathode plate and an anode plate are arranged to face each other through a separator; a casing adapted to house the electrode assembly therein; and a cover assembly comprising a metallic cover having a cylindrical side wall and a lower surface horizontally elongated from the cylindrical side wall toward a central axis of the casing, wherein a lower edge portion of the lower surface is welded to a distal end of an open end of the casing such that the lower end of the cylindrical side wall is located on the distal end of the open portion of the casing, the cylindrical side wall being externally exposed after welding, and the lower surface not contacting an inner wall of the casing; wherein an open portion of the casing has a substantially flat outer wall to a location corresponding to the distal end.