Battery and method for manufacturing same
The present disclosure aims, in a battery, to suppress intrusion of foreign materials generated by sputtering in the battery while a decrease in battery capacity is suppressed. A battery according to one embodiment of the present disclosure includes an exterior package can ( 51 ) which receives an electrode body, the electrode body includes a lead connected to one of a positive electrode and a negative electrode, the lead has a U-shaped portion ( 18 ) having a cross-sectional U shape formed by folding, and at least a part of a portion of the U-shaped portion which is in contact with the exterior package can ( 51 ) and the exterior package can ( 51 ) are welded to each other with a welding portion formed by energy beams radiated from the outside of the exterior package can ( 51 ).
1 . A battery comprising:
an electrode body in which at least one positive electrode and at least one negative electrode are spirally wound with at least one separator interposed therebetween; and
a cylindrical exterior package can which receives the electrode body within a closed interior of the exterior package can,
wherein the electrode body includes a lead connected to one of the positive electrode and the negative electrode, wherein the lead is enclosed within the closed interior of the cylindrical exterior package can and interposed between the electrode body and a circular base portion of the cylindrical exterior package can,
the lead is an elongated rectangular piece of metal having an end portion thereof protruding from the electrode body toward the circular base portion of the cylindrical exterior package can, wherein the end portion of the lead has an L-shaped profile defined by:
a first section that extends parallel to a winding axis of the electrode body, and
a second section that extends parallel to the circular base portion of the cylindrical exterior package can,
wherein the second section of the end portion of the lead defines a U-shaped portion having a cross-sectional U shape including an inside section, and an outside section opposite the inside section,
wherein the circular base portion of the cylindrical exterior package can, the inside section, and the outside section are configured to overlap each other when viewed in a thickness direction of the circular base portion of the cylindrical exterior package can, and
the cylindrical exterior package can and at least a part of a portion of the U-shaped portion which is in contact with the cylindrical exterior package can are welded to each other with a welding portion formed by energy beams radiated from the outside of the cylindrical exterior package can,
wherein the welding portion extends from the circular base portion of the cylindrical exterior package can through an entirety of the outside section and only a part less than entirety of the inside section in the thickness direction of the circular base portion of the cylindrical exterior package can, and
the welding portion is located to face a winding core portion including the winding central axis of the electrode body.
2 . The battery according to claim 1 ,
wherein the lead is a negative electrode lead bonded to a winding-finish side end portion of the negative electrode.
3 . The battery according to claim 2 ,
wherein a front end of the negative electrode lead at a side of the U-shaped portion is folded to the inside of the exterior package can so as to be apart from the exterior package can.
4 . The battery according to claim 2 ,
wherein a front end of the negative electrode lead at a side of the U-shaped portion is folded to the outside which is a side of the exterior package can so as to be in contact with the exterior package can.
5 . The battery according to claim 1 ,
wherein the lead is a negative electrode lead connected to a winding-start side end portion of the negative electrode.
6 . The battery according to claim 5 ,
wherein a front end of the negative electrode lead at a side of the U-shaped portion is folded to the inside of the exterior package can so as to be apart from the exterior package can.
7 . The battery according to claim 5 ,
wherein a front end of the negative electrode lead at a side of the U-shaped portion is folded to the outside which is a side of the exterior package can so as to be in contact with the exterior package can.
8 . A method for manufacturing the battery according to claim 1 , the method comprising:
a welding step of welding the lead to the exterior package can while the lead connected to one of the positive electrode and the negative electrode is folded,
wherein in the welding step, energy beams are radiated from the outside of the exterior package can to an area of the exterior package can which faces a part of the U-shaped portion of the lead in contact with the exterior package can to weld the exterior package can and the lead to each other with the welding portion.
9 . The method for manufacturing the battery, according to claim 8 ,
wherein the lead is a negative electrode lead bonded to a winding-finish side end portion of the negative electrode or a winding-start side end portion of the negative electrode.
10 . The method for manufacturing the battery, according to claim 9 ,
wherein a front end of the negative electrode lead at a side of the U-shaped portion is folded to the inside of the exterior package can so as to be apart from the exterior package can or is folded to the outside which is a side of the exterior package can so as to be in contact with the exterior package can.
11 . The battery according to claim 1 ,
wherein the battery further comprises an insulating plate interposed between the electrode body and the U-shaped portion of the lead in the thickness direction of the portion of the exterior package can,
wherein the inside section of the U-shaped portion directly contacts the insulating plate.
12 . The battery according to claim 1 ,
wherein the battery further comprises an insulating plate interposed between the electrode body and the U-shaped portion of the lead in the thickness direction of the portion of the exterior package can,
wherein the insulating plate comprises a through hole overlapping a portion of the inside section of the U-shaped portion, when viewed in in the thickness direction of the portion of the exterior package can.
13 . The battery according to claim 1 ,
wherein the battery further comprises an insulating plate interposed between the electrode body and the U-shaped portion of the lead in the thickness direction of the portion of the exterior package can,
wherein the insulating plate overlaps an entirety of the inside section of the U-shaped portion, when viewed in in the thickness direction of the portion of the exterior package can.
14 . A method for manufacturing a battery comprising:
an electrode body in which at least one positive electrode and at least one negative electrode are spirally wound with at least one separator interposed therebetween; and
a cylindrical exterior package can which receives the electrode body within a closed interior of the exterior package can,
wherein the electrode body includes a lead connected to one of the positive electrode and the negative electrode, wherein the lead is enclosed within the closed interior of the cylindrical exterior package can and interposed between the electrode body and a circular base portion of the cylindrical exterior package can,
the lead is an elongated rectangular piece of metal having an end portion thereof protruding from the electrode body toward the circular base portion of the cylindrical exterior package can, wherein the end portion of the lead has an L-shaped profile defined by:
a first section that extends parallel to a winding axis of the electrode body, and
a second section that extends parallel to the circular base portion of the cylindrical exterior package can,
wherein the second section of the end portion of the lead defines a U-shaped portion having a cross-sectional U shape including an inside section, and an outside section opposite the inside section,
wherein the circular base portion of the cylindrical exterior package can, the inside section, and the outside section are configured to overlap each other when viewed in a thickness direction of the circular base portion of the cylindrical exterior package can, and
the cylindrical exterior package can and at least a part of a portion of the U-shaped portion which is in contact with the cylindrical exterior package can are welded to each other with a welding portion formed by energy beams radiated from the outside of the cylindrical exterior package can,
wherein the welding portion extends from the circular base portion of the cylindrical exterior package can through an entirety of the outside section and only a part less than entirety of the inside section in the thickness direction of the circular base portion of the cylindrical exterior package can, and
the welding portion is located to face a winding core portion including the winding central axis of the electrode body,
the method comprising:
a welding step of welding the lead to the exterior package can while the lead connected to one of the positive electrode and the negative electrode is folded,
wherein in the welding step, energy beams are radiated from the outside of the exterior package can to an area of the exterior package can which faces a part of the U-shaped portion of the lead in contact with the exterior package can to weld the exterior package can and the lead to each other with the welding portion,
wherein in the welding step, a pressing bar is inserted into the exterior package can to press the U-shaped portion against the portion of the exterior package can.