This battery comprises an electrode body, an outer package, an opening sealing element, and an auxiliary electrode. The auxiliary electrode has: a first joint part that is welded to an outer circumferential surface of a cylindrical part of the outer package; a plate-like first upward extension part that extends from the first joint part toward the side of an open end of the outer package; and a plate-like external connection part that extends from the first upward extension part in a direction different from that of the first upward extension part so as to be connected to another conductor member. The cylindrical part has a groove in which an outer circumferential surface is indented in such a manner as to make an inner circumferential surface protrude.
1 . A battery, comprising:
an electrode assembly obtained by winding a first electrode and a second electrode with a separator therebetween;
an outer package that has a cylindrical part having a cylindrical shape, an open end formed at one end of the cylindrical part, and a bottom closing the other end of the cylindrical part, and that stores the electrode assembly therein, and that is electrically connected to the first electrode;
a sealing assembly that closes the open end of the outer package together with a gasket, and is electrically connected to the second electrode; and
an auxiliary electrode having a first joint part that is welded to an outer circumferential surface of the cylindrical part, a plate-shaped first upward extension part that extends from the first joint part toward the open end, and a plate-shaped external connection part that extends from the first upward extension part in a direction different from a direction of the first upward extension part, and is connected to another conductive member, wherein
the cylindrical part has a groove having the outer circumferential surface dented so as to protrude an inner circumferential surface of the cylindrical part,
the sealing assembly is disposed on the groove with the gasket therebetween, and
the first joint part is joined to at least one of a portion of an inside of the groove, on a side nearer to the bottom than a valley position of the groove, and a portion of the outer circumferential surface of the cylindrical part located between the groove and the electrode assembly in a winding axis direction of the electrode assembly.
2 . The battery according to claim 1 , wherein
the first joint part has a downward extension part that is continuous from an end on a side of the electrode assembly of the first upward extension part, and extends to a portion beyond a lower end of the groove,
a first cutout is formed in a portion of the downward extension part facing the groove,
the downward extension part has a first bent part that is adjacent to the first cutout, and bent on a side of the outer package, and
the first bent part is joined to the groove.
3 . The battery according to claim 2 , wherein
the first cutout has a U-shape in which a side of the electrode assembly is open, and
the first bent part is disposed in a portion surrounded by the first cutout in the downward extension part.
4 . The battery according to claim 1 , wherein
the auxiliary electrode has a second joint part that is welded away from the first joint part in a circumferential direction of the cylindrical part of the outer package, and a second upward extension part that extends from the second joint part toward the open end, and
the first upward extension part and the second upward extension part are connected at two positions separated in the circumferential direction of the external connection part.
5 . The battery according to claim 2 , wherein
the auxiliary electrode has a second joint part that is joined apart from the first joint part in a circumferential direction of the cylindrical part of the outer package, and a second upward extension part that extends from the second joint part toward the open end,
the first upward extension part and the second upward extension part are connected at two positions separated in the circumferential direction of the external connection part,
the second joint part has a second downward extension part that is continuous from an end on a side of the electrode assembly of the second upward extension part, and extends to a portion beyond a lower end of the groove,
a second cutout is formed in a portion of the second downward extension part facing the groove,
the second downward extension part has a second bent part that is adjacent to the second cutout, and bent toward the outer package, and
the second bent part is joined to the groove.
6 . The battery according to claim 5 , wherein
the second cutout has a U-shape in which a side of the electrode assembly is open, and
the second bent part is disposed in a portion surrounded by the second cutout in the second downward extension part.
7 . The battery according to claim 1 , wherein
the auxiliary electrode has at least one support part that extends in a circumferential direction of the cylindrical part and is inserted into the groove.