A battery includes an electrically-conductive battery can ( 1 ) for accommodating a spirally-wound electrode assembly ( 3 ) in which an electrolyte solution is impregnated. The battery can has an open end and a closed end, and to the open end, an electrically-conductive sealing plate ( 5 ) is fixed being insulated from the battery can ( 1 ). A positive electrode ( 31 ) and a negative electrode ( 33 ) project from respective opposing ends of the spirally-wound electrode assembly ( 3 ), and a positive electrode current collector plate ( 4 ) and a negative electrode current collector plate ( 2 ) are joined to the respective projecting edges of the electrodes ( 31 ), ( 33 ). Electrically-conductive leads ( 45 ), ( 46 ) connect the positive electrode current collector plate ( 4 ) and the sealing plate ( 5 ) together. The negative electrode current collector plate ( 2 ) and the battery can ( 1 ) are electrically connected to each other. In a surface of the sealing plate ( 5 ) facing the spirally-wound electrode assembly ( 3 ), one or more electrically-conductive connecting protrusions ( 53 ), ( 54 ), to which the leads ( 45 ), ( 46 ) are welded, are provided protruding toward the spirally-wound electrode assembly ( 3 ). |