A battery includes a cover for sealing an opening of a battery case which contains an electrode assembly therein and current collectors for electrically connecting external terminals whose at least parts are disposed outside of the cover to the electrode assembly, respectively. Gaskets are interposed between a lower surface of the cover and the current collectors, respectively. In the gasket, a caulked portion is contained in an engagement recess formed at the lower surface of the cover. In contrast, the entire gasket is contained in another engagement recess formed at the lower surface.