BATTERY AND METHOD FOR PRODUCING SAME

A battery (1) houses an electrode body (9) inside a battery case (2). The battery case (2) has a bottomed cylindrical case body (3) having an opening (3k), and a plate-like lid member (4) that is inserted in the opening (3k) so as to seal the opening. The opening (3k) and a lid peripheral edge section (4f) are welded in an airtight manner by an energy beam (LS) irradiated from the outside in the thickness direction (TH) of the lid member (4). At a specific location (11), the inner peripheral surface (3ia) of the opening (3k) of the case body (3) and the peripheral edge surface (4ua) of the lid peripheral edge section (4f) of the lid member (4) are welded in a state in which said inner peripheral surface and peripheral edge surface are in close contact with each other. The shape of a bead (10a) at the specific location forms a fan shape having a central angle (θ) of 160 to 200 degrees in a cross section in the circumferential direction (SH) of the bead, and the center of the fan shape (10ac) is positioned on the inner peripheral surface (3ia) and the peripheral edge surface (4ua).