A rechargeable battery is disclosed. In one aspect, the battery includes an electrode assembly having an uncoated region, a case accommodating the electrode assembly therein and an insulation plate disposed on the uncoated region of the electrode assembly. The battery also includes a gasket formed on the insulation plate, wherein the gasket comprises a support supported by and contacting an upper surface of the insulation plate, wherein the support comprises an inner side surface and an outer side surface, and wherein at least one of the inner and outer side surfaces forms an obtuse angle with respect to the upper surface of the insulation plate. The battery further includes a cap assembly contacting the gasket and connected to the uncoated region of the electrode assembly through a lead tab.