Patent ID: 7572544
Filing Date: 2009-08-11
Classification: H01M,Y02E,Y02P

Abstract:
1. A sealed rechargeable battery including an electrode plate unit consisting of a positive electrode and a negative electrode wound around with a separator interposed therebetween, the electrode plate unit being encased in a metallic case with a bottom together with liquid electrolyte, and a closure assembly attached to the case by crimping the case end periphery to provide a seal, the closure assembly including a metallic foil and a metallic safety vent joined together and an outer gasket interposed between the closure assembly and the case, the metallic foil having an upwardly protruding portion and the metallic safety vent having a downwardly protruding portion, wherein, upon the metallic foil is placed a first spacer having an aperture that is larger than the upwardly protruding portion of the metallic foil but smaller than the outside diameter of the foil, and upon the metallic safety vent is placed either a second spacer and a metallic cap, or a metallic cap only, the second spacer and/or metallic cap having an aperture that is larger than the downwardly protruding portion of the metallic safety vent but smaller than the outside diameter of the safety vent, and an inner gasket is disposed on the first spacer, wherein the inside diameter of an aperture of the first spacer and the inside diameter of an aperture of the metallic cap and/or second spacer are smaller than the inside diameter of an aperture of the inner gasket.