Patent ID: 7459232
Filing Date: 2008-12-02
Classification: H01M,Y02E,Y02P,Y10T

Abstract:
1. A secondary battery, comprising: an electrode assembly including a positive plate, a negative plate and a separating plate interposed between the positive plate and the negative plate; a cylindrical container having an opening for receiving the electrode assembly inside the container; a cap plate crimped to the opening of the container to seal the container; and a safety valve formed on the region where the container and the cap plate are crimped, wherein the safety valve is formed on a sealing part where a top peripheral edge of the container defining the opening is curled on and contacts the entire circumference of the cap plate, the sealing part including a first sealing part formed with a predetermined crimping strength and a second sealing part formed with a weaker crimping strength than the first sealing part, the second sealing part forming the safety valve.