Patent ID: 7851078
Filing Date: 2010-12-14
Classification: H01M,Y02E,Y02P

Abstract:
1. A secondary battery, comprising: an electrode assembly; a can comprising an opening that receives the electrode assembly through the opening; a cap assembly that covers and seals the opening; a vent formed on aside of the can, perpendicular to the opening with a wall thickness thinner than a wall thickness of the can so that the vent opens to discharge internal pressure within the can when the internal pressure exceeds a pre-determined value that the can and the cap assembly can withstand without rupturing, wherein the vent comprises a cut on the side of the can defining a shape of the vent so that the vent opens along the cut, wherein the shape of the vent comprises an open polygon or an open curve with an open portion oriented generally away from the opening of the can; and a shock absorbing portion formed proximal to the vent with a wall thickness thicker than the vent, wherein the shock absorbing portion comprises at least one path of groove or indentation on the said side of the can wherein the shock absorbing portion comprises the groove or indentation formed inward on the side of the can.