A sealed battery including a battery case that includes a cylindrical exterior can having a bottom and an opening sealing body that closes an opening of the outer can; a gasket that is arranged between the exterior can and the opening sealing body; and an electrode body. The opening sealing body includes: a metal plate with an annular part to which an electrode lead is electrically connected, and a disconnecting part that is separated from the annular part when the inner pressure of the battery case exceeds a predetermined threshold; a valve body that is arranged further to the outside of the battery case than the metal plate; and an insulating plate that is arranged between the metal plate and the valve body. The insulating plate or the gasket is provided with an elastic deformation part that deforms in the direction of the valve body.