A battery comprising: an exterior body having a bottom wall, a pair of first side walls extending from the bottom wall and facing each other, a pair of second side walls extending from the bottom wall and facing each other, and an opening facing the bottom wall; a sealing plate that seals the opening of the exterior body; at least one winding electrode body in which a strip-shaped positive electrode and a strip-shaped negative electrode are laminated with each other via a strip-shaped separator and wound about a winding axis; a positive electrode tab group that includes a plurality of positive electrode tabs provided at an end in a winding axis direction of the winding electrode body and is electrically connected to the positive electrode; and a negative electrode tab group that includes a plurality of negative electrode tabs provided at an end in the winding axis direction of the winding electrode body and is electrically connected to the negative electrode, wherein the winding electrode body has a flat shape having a pair of curvature parts having a curved outside surface and a flat part that connects the pair of curvature parts to each other and has a flat outside surface and is accommodated in the exterior body so that one of the curvature parts faces the sealing plate and the other thereof faces the bottom wall of the exterior body, and wherein, when a line perpendicular to the winding axis of the winding electrode body and perpendicular to the bottom wall is assumed as L1, a portion positioned at an outermost periphery of the negative electrode in at least one of the pair of the curvature parts faces a portion positioned on a winding inner peripheral side of the negative electrode via the separator and not via the positive electrode on the line L1. an exterior body having a bottom wall, a pair of first side walls extending from the bottom wall and facing each other, a pair of second side walls extending from the bottom wall and facing each other, and an opening facing the bottom wall; a sealing plate that seals the opening of the exterior body; at least one winding electrode body in which a strip-shaped positive electrode and a strip-shaped negative electrode are laminated with each other via a strip-shaped separator and wound about a winding axis; a positive electrode tab group that includes a plurality of positive electrode tabs provided at an end in a winding axis direction of the winding electrode body and is electrically connected to the positive electrode; and a negative electrode tab group that includes a plurality of negative electrode tabs provided at an end in the winding axis direction of the winding electrode body and is electrically connected to the negative electrode, wherein the winding electrode body has a flat shape having a pair of curvature parts having a curved outside surface and a flat part that connects the pair of curvature parts to each other and has a flat outside surface and is accommodated in the exterior body so that one of the curvature parts faces the sealing plate and the other thereof faces the bottom wall of the exterior body, and wherein, when a line perpendicular to the winding axis of the winding electrode body and perpendicular to the bottom wall is assumed as L1, a portion positioned at an outermost periphery of the negative electrode in at least one of the pair of the curvature parts faces a portion positioned on a winding inner peripheral side of the negative electrode via the separator and not via the positive electrode on the line L1.