Abstract: A secondary battery includes an outer can, a sealing body sealing an opening of the outer can, an electrode group housed together with an electrolyte inside the outer can, and a positive electrode current collector arranged between the electrode group and the sealing body. The positive electrode current collector has a current collector center through hole provided at a position facing an electrode group through hole of the electrode group. The sealing body includes a lid plate having an exhaust hole at the center, a valve body arranged at a position closing the exhaust hole from the outside of the lid plate, and a positive electrode terminal electrically connected to the lid plate and housing inside with the valve body pressed toward the lid plate. An inner diameter dimension DC of the current collector center through hole of the positive electrode current collector is equal to or less than an inner diameter dimension DL of the exhaust hole.

Abstract: A current collecting lead is interposed between a sealing body and a positive electrode current collector for connecting the sealing body and the positive electrode current collector, the sealing body including a positive electrode terminal, the positive electrode current collector being attached to an electrode group, the current collecting lead including: a top wall portion positioned on the side of the sealing body; leg portions positioned on the side of the positive electrode current collector and that face the top wall portion; and a pair of side wall portions that extend between side edges of the top wall portion and side edges of the leg portions and that face each other, a first corner portion and a second corner portion formed by the top wall portion and the side wall portions and a third corner portion and a fourth corner portion formed by the leg portions and the side wall portions being rounded corners that are curved.

Abstract: A secondary battery includes an outer can, a sealing body sealing an opening of the outer can, an electrode group housed together with an electrolyte inside the outer can, and a positive electrode current collector arranged between the electrode group and the sealing body. The positive electrode current collector has a current collector center through hole provided at a position facing an electrode group through hole of the electrode group. The sealing body includes a lid plate having an exhaust hole at the center, a valve body arranged at a position closing the exhaust hole from the outside of the lid plate, and a positive electrode terminal electrically connected to the lid plate and housing inside with the valve body pressed toward the lid plate. An inner diameter dimension DC of the current collector center through hole of the positive electrode current collector is equal to or less than an inner diameter dimension DL of the exhaust hole.

Abstract: A nickel-hydrogen secondary battery includes: an outer can; a sealing body including a positive electrode terminal, the sealing body sealing an opening of the outer can; an electrode group formed by placing a positive electrode and a negative electrode on top of each other with a separator therebetween and spirally winding the positive electrode and the negative electrode, the electrode group housed in the outer can along with an alkaline electrolyte; a positive electrode current collector connected to positive electrode connection edge portion protruding from one end surface of the electrode group; and a current collecting lead connecting the positive electrode current collector and the sealing body, wherein a relationship between a deformation resistance A of a material a and a deformation resistance B of a material b satisfies a relationship of A<B, wherein the material a is a material of the current collecting lead, and the material b is a material of the positive electrode current collector.

Abstract: A current collecting lead is interposed between a sealing body and a positive electrode current collector for connecting the sealing body and the positive electrode current collector, the sealing body including a positive electrode terminal, the positive electrode current collector being attached to an electrode group, the current collecting lead including: a top wall portion positioned on the side of the sealing body; leg portions positioned on the side of the positive electrode current collector and that face the top wall portion; and a pair of side wall portions that extend between side edges of the top wall portion and side edges of the leg portions and that face each other, a first corner portion and a second corner portion formed by the top wall portion and the side wall portions and a third corner portion and a fourth corner portion formed by the leg portions and the side wall portions being rounded corners that are curved.

Abstract: A nickel-hydrogen secondary battery includes: an outer can; a sealing body including a positive electrode terminal, the sealing body sealing an opening of the outer can; an electrode group formed by placing a positive electrode and a negative electrode on top of each other with a separator therebetween and spirally winding the positive electrode and the negative electrode, the electrode group housed in the outer can along with an alkaline electrolyte; a positive electrode current collector connected to positive electrode connection edge portion protruding from one end surface of the electrode group; and a current collecting lead connecting the positive electrode current collector and the sealing body, wherein a relationship between a deformation resistance A of a material a and a deformation resistance B of a material b satisfies a relationship of A<B, wherein the material a is a material of the current collecting lead, and the material b is a material of the positive electrode current collector.

Abstract: A negative-electrode plate 22 for use in a cylindrical cell, intended to be laid over a positive-electrode plate 21 with a separator 23 interposed between and rolled to form a cylindrical electrode body 20, with the positive-electrode plate 21 inside, the electrode body being arranged in a bottomed cylindrical outer can 10 to form the cylindrical cell, comprises a first negative-electrode part 22a which is to face the positive-electrode plate 21 on either side, with the separator 23 between, when formed into the electrode body 20, and a second negative-electrode part 22b which is to form the innermost circumference of the electrode body 20 and face the positive-electrode plate 21 only on one side, with the separator 23 between, when formed into the electrode body 20, the second negative-electrode part 22b being lower in negative-electrode active material density than the first negative-electrode part 22a.

Abstract: A negative electrode for a nickel-hydrogen rechargeable battery is a strip-shaped negative electrode, the negative electrode being formed of a core body and a negative mixture layer covering the core body and containing hydrogen-storage alloy particles, including a main section, both sides of which face the positive electrode with the separator intervening therebetween as viewed in a rolled state where the negative electrode forms the electrode group with the positive electrode and the separator, and an outermost circumferential portion and an innermost circumferential portion that are protruding from ends of the main section in a rolling direction and facing the positive electrode with the separator intervening therebetween only with one side, wherein the hydrogen-storage alloy particles contained in the outermost circumferential portion and the innermost circumferential portion have an average diameter larger than an average diameter of the hydrogen-storage alloy particles contained in the main section.

Abstract: A negative-electrode plate 22 for use in a cylindrical cell, intended to be laid over a positive-electrode plate 21 with a separator 23 interposed between and rolled to form a cylindrical electrode body 20, with the positive-electrode plate 21 inside, the electrode body being arranged in a bottomed cylindrical outer can 10 to form the cylindrical cell, comprises a first negative-electrode part 22a which is to face the positive-electrode plate 21 on either side, with the separator 23 between, when formed into the electrode body 20, and a second negative-electrode part 22b which is to form the innermost circumference of the electrode body 20 and face the positive-electrode plate 21 only on one side, with the separator 23 between, when formed into the electrode body 20, the second negative-electrode part 22b being lower in negative-electrode active material density than the first negative-electrode part 22a.

Abstract: A negative electrode for a nickel-hydrogen rechargeable battery is a strip-shaped negative electrode, the negative electrode being formed of a core body and a negative mixture layer covering the core body and containing hydrogen-storage alloy particles, including a main section, both sides of which face the positive electrode with the separator intervening therebetween as viewed in a rolled state where the negative electrode forms the electrode group with the positive electrode and the separator, and an outermost circumferential portion and an innermost circumferential portion that are protruding from ends of the main section in a rolling direction and facing the positive electrode with the separator intervening therebetween only with one side, wherein the hydrogen-storage alloy particles contained in the outermost circumferential portion and the innermost circumferential portion have an average diameter larger than an average diameter of the hydrogen-storage alloy particles contained in the main section.