Patent attributes
A closed battery, according to the invention, comprises a substantially flat box-type outer case 60 having electrical conductivity, provided with an opening on one side in the longitudinal direction thereof and other peripheral sides that are closed, a spiral electrode body 21 housed in the outer case, comprising a positive electrode, a negative electrode, and a separator interposed therebetween, an electrode current collector tab 21a larger in thickness than a core body, welded to a cut and raised piece that is cut and raised from an exposed part of the core body of one of the electrodes of the spiral electrode body, and a sealing plate 50 for covering and sealing the opening of the outer case, wherein the outer case is sealed by laser-welding with the electrode current collector tab being clamped between the rim of the opening and the sealing plate when sealing the opening of the outer case.
