A sealed battery with a battery case that includes a bottomed cylindrical outer can and an opening-sealing body that closes an opening section of the outer can; and an electrode body that is accommodated inside the battery case. The opening-sealing body includes a metal plate, and the metal plate includes a protruding section that bulges toward the outside of the battery cast, and a flange section that is formed on the circumference of the protruding section. The protruding section includes an inclination section that inclines inward from the radial outside of the opening sealing body so as to be progressively separated from the electrode body, wherein a thin wall section, which has a thickness less than portions other than the inclination section and is preferably broken when the inner pressure of the battery case exceeds a predetermined threshold, is formed in at least a portion of the inclination section.