Patent ID: 7629076
Filing Date: 2009-12-08
Classification: H01M,Y02E,Y02P,Y10T

Abstract:
1. A battery comprising: a cylindrical battery case having a bottom and an electrode plate group accommodated in the battery case, the electrode plate group has a strip-shaped positive electrode plate and a strip-shaped negative electrode plate spirally wound with a separator interposed therebetween, wherein an opening at an upper end of the battery case is sealed by a sealing member with an insulation gasket interposed therebetween, an annular supporting ledge protruding radially outward from an upper circumferential end of the battery case to form an enlarged portion having a diameter which is greater than a diameter of at least a portion of the battery case which accommodates the electrode plate group, the annular supporting ledge further does not include an annular groove formed radially inwardly of the battery case, a collector having one polarity is bonded to an end of the electrode plate having the one polarity that projects upward from the electrode plate group, to the collector of the one polarity, one end of a connection lead is bonded in an arrangement in which a notch formed at the one end of the connection lead is in agreement with a part of a hole edge of an electrolyte-injection hole at the center of the collector of the one polarity, the other end of the connection lead, which is a tip end of a folded portion extending from the one end, is bonded to a portion of the sealing member, the portion being displaced from a vent opening at the center of the sealing member toward the folded portion of the connection lead, a peripheral edge portion of the sealing member is supported by the supporting ledge with the insulation gasket interposed therebetween, and the peripheral edge portion of the sealing member is fastened in a horizontal direction with the insulation gasket interposed therebetween.