Abstract: A manufacturing method of a battery including attaching a first current collector lead to a first electrode plate; attaching a second current collector lead to a second electrode plate; a step of fabricating a wound electrode group by winding the first electrode plate and the second electrode plate around a winding core member with a separator interposed therebetween; accommodating the wound electrode group in a closed-end cylindrical metal case being a first electrode terminal; joining the first current collector lead to an inner sidewall surface of the metal case (step X); joining the second current collector lead to a sealing member being a second electrode terminal; and sealing the metal case, before step X, a joint portion of the first current collector lead with the inner sidewall surface of the metal case is curved in a same direction as a curve of the inner sidewall surface of the metal case.

Abstract: A battery includes a first electrode plate, a second electrode plate, a separator interposed between the first and second electrode plates, a closed-end cylindrical metal case accommodating these three elements, and a sealing member sealing an opening of the metal case with an insulating member interposed therebetween. The first and second electrode plates are wound with the separator interposed therebetween to form a wound electrode group. A center axis portion of the wound electrode group is substantially the same as a center axis of a cylinder of the metal case, and contains no power-generating element. A first current collector lead coupled to the first electrode plate extends toward the opening of the metal case, and joined to an inner sidewall surface of the metal case. A second current collector lead coupled to the second electrode plate extends toward the opening of the metal case, and joined to the sealing member.

Abstract: A battery includes a first electrode plate, a second electrode plate, a separator interposed between the first and second electrode plates, a closed-end cylindrical metal case accommodating these three elements, and a sealing member sealing an opening of the metal case with an insulating member interposed therebetween. The first and second electrode plates are wound with the separator interposed therebetween to form a wound electrode group. A center axis portion of the wound electrode group is substantially the same as a center axis of a cylinder of the metal case, and contains no power-generating element. A first current collector lead coupled to the first electrode plate extends toward the opening of the metal case, and joined to an inner sidewall surface of the metal case. A second current collector lead coupled to the second electrode plate extends toward the opening of the metal case, and joined to the sealing member.

Abstract: A wound electrode group includes an electrode stack that is formed by laminating a strip of positive electrode plate, a strip of negative electrode plate, and a pair of separators interposed therebetween. When the electrode stack is wound, a difference L in length between an inner turn and an adjacent outer turn satisfies L=2t?+(W×k), where t is a thickness of the electrode stack, W is a maximum diameter of a cross section of the wound electrode group, and k is a coefficient that is preset in accordance with expansion coefficients of active materials of the positive and negative electrode plates and is within a range from 0.005 to 0.05.

Abstract: A wound electrode group includes an electrode stack that is formed by laminating a strip of positive electrode plate, a strip of negative electrode plate, and a pair of separators interposed therebetween. When the electrode stack is wound, a difference L in length between an inner turn and an adjacent outer turn satisfies L=2t?+(W×k), where t is a thickness of the electrode stack, W is a maximum diameter of a cross section of the wound electrode group, and k is a coefficient that is preset in accordance with expansion coefficients of active materials of the positive and negative electrode plates and is within a range from 0.005 to 0.05.