Riveting structure of electrode terminal, and cylindrical battery cell, battery pack and vehicle including the same
The riveting structure of an electrode terminal for a battery includes a battery housing having a bottom; an electrode terminal riveted through a hole formed in the bottom of the battery housing; and a gasket between the electrode terminal and the battery housing. Also, the electrode terminal includes a body portion inserted into the hole; an outer flange portion extending along an outer surface of the bottom of the battery housing from a first side of the body portion exposed through the outer surface; an inner flange portion extending toward an inner surface of the bottom of the battery housing from a second side of the body portion exposed through the inner surface; and a flat portion on the second side of the body portion.
1. A riveting structure of an electrode terminal for a battery, the riveting structure comprising:
a battery housing having a bottom;
an electrode terminal riveted through a hole formed in the bottom of the battery housing; and
a gasket between the electrode terminal and the battery housing,
wherein the electrode terminal includes:
a body portion inserted into the hole;
an outer flange portion extending along an outer surface of the bottom of the battery housing in a width direction from a first side of the body portion exposed through the outer surface;
an inner flange portion extending toward an inner surface of the bottom of the battery housing from a second side of the body portion exposed through the inner surface;
a flat portion on the second side of the body portion; and
a recess exposed between the inner flange portion and the flat portion in the width direction.
2. The riveting structure of the electrode terminal according to claim 1 , wherein an angle between the inner flange portion and the inner surface of the bottom of the battery housing is in a range of 2° to 60°.
3. The riveting structure of the electrode terminal according to claim 1 , wherein the recess has an asymmetric cross section.
4. The riveting structure of the electrode terminal according to claim 3 , wherein the asymmetric cross section of the recess includes a sidewall and an inclined surface of the inner flange portion connected to an end of the sidewall.
5. The riveting structure of the electrode terminal according to claim 1 , wherein the inner flange portion has a gradually decreasing thickness in a direction extending away from the body portion.
6. The riveting structure of the electrode terminal according to claim 1 , wherein the gasket includes:
an outer gasket between the outer flange portion and the outer surface of the bottom of the battery housing; and
an inner gasket between the inner flange portion and the inner surface of the bottom of the battery housing,
wherein the inner gasket has a varying thickness.
7. The riveting structure of the electrode terminal according to claim 6 , wherein the inner gasket extends radially outwardly further than the inner flange portion.
8. The riveting structure of the electrode terminal according to claim 6 , wherein a height of the flat portion is equal to or larger than a height of an end of the inner gasket based on the inner surface of the bottom of the battery housing.
9. The riveting structure of the electrode terminal according to claim 1 , wherein a height of the flat portion is equal to or larger than a height of the inner flange portion based on the inner surface of the bottom of the battery housing.
10. The riveting structure of the electrode terminal according to claim 1 , wherein a radius from a center of the body portion to an edge of the outer flange portion is 10% to 70% of a radius of the bottom of the battery housing.
11. The riveting structure of the electrode terminal according to claim 1 , wherein a radius from a center of the body portion to an edge of the flat portion is 4% to 30% of a radius of the bottom of the battery housing.
12. A battery, comprising:
an electrode assembly comprising a first electrode and a second electrode wound with a separator therebetween, wherein each of the first electrode and the second electrode has a first portion coated with an active material, and a second portion, and wherein the second portion of the first electrode and the second portion of the second electrode are extended from opposite ends of the electrode assembly and exposed to the outside of the separator;
a battery housing accommodating the electrode assembly and electrically connected to the first electrode, the battery housing having a first end with a first opening and a second end opposite the first end;
an electrode terminal riveted through a hole formed in the second end of the battery housing and electrically connected to the second electrode, the electrode terminal including:
a body portion inserted into the hole;
an outer flange portion extending from the body portion in a width direction along an outer surface of the second end of the battery housing from a first side of the body portion exposed through the outer surface;
an inner flange portion extending toward an inner surface of the second end of the battery housing from a second side of the body portion exposed through the inner surface;
a flat portion in the second side of the body portion; and
a recess exposed between the inner flange portion and the flat portion in the width direction;
a gasket between the electrode terminal and the battery housing; and
a sealing body sealing the first opening of the first end of the battery housing.
13. The battery according to claim 12 , wherein the battery housing includes a beading portion formed in a region adjacent to the first end of the battery housing which is pressed-in into the battery housing, and
wherein the sealing body includes a cap having no polarity and a sealing gasket between an edge of the cap and the first end of the battery housing.
14. The battery according to claim 13 , wherein the battery housing further includes a crimping portion extended and bent into the inside of the battery housing to surround and fix the edge of the cap together with the sealing gasket.
15. The battery according to claim 13 , further comprising:
a first current collecting unit coupled to the second portion of the first electrode; and
a second current collecting unit coupled to the second portion of the second electrode plate,
wherein at least a part of an edge of the first current collecting unit not in contact with the second portion of the first electrode is between the beading portion and the sealing gasket and fixed by the crimping portion, and
wherein at least a part of the second current collecting unit is coupled to the flat portion of the electrode terminal.
16. The battery according to claim 15 , wherein at least a part of the edge of the first current collecting unit is fixed to an inner circumference of the beading portion adjacent to the crimping portion by welding.
17. The battery according to claim 12 , wherein the gasket includes:
an outer gasket between the outer flange portion and the outer surface of the second end of the battery housing; and
an inner gasket between the inner flange portion and the inner surface of the second end of the battery housing.
18. The battery according to claim 17 , wherein an end of the inner gasket is exposed to the outside of the inner flange portion.
19. The battery according to claim 12 , wherein a first bus bar terminal is electrically coupled to a surface of the electrode terminal, and a second bus bar terminal is electrically coupled to the outer surface of the second end of the battery housing.
20. The battery according to claim 19 , wherein the first bus bar terminal overlaps with the electrode terminal on a plane to form a first overlapping region, and the second bus bar terminal overlaps with the outer surface of the second end of the battery housing to form a second overlapping region, and
wherein a diameter of the electrode terminal and a width of the outer surface of the second end of the battery housing satisfy the following relational expression,
W 1 ≤E 1 ≤D− 2 R d −2 G− 2 W 2
E 2 =0.5*( D− 2 R d −2 G−E 1 )
where E 1 is a diameter of the outer flange portion of the electrode terminal, E 2 is a width of an exposed surface parallel to a surface of the electrode terminal in the outer surface of the second end of the battery housing, D is a diameter of the battery housing, R d is a width of a round region at an edge of the battery housing measured on a plane, G is an exposure width of the outer gasket through an edge of the electrode terminal, W 1 is a maximum value among distances between any two points selected in an edge of the first overlapping region, and W 2 is a maximum value among distances between two points where a plurality of linear lines passing through the center of the electrode terminal meet an edge of the second overlapping region.
21. The battery according to claim 12 , wherein a ratio of a diameter of the battery to a height of the battery is greater than 0.4.
22. A battery pack, comprising a plurality of batteries according to claim 12 .
23. The battery pack according to claim 22 , wherein the plurality of batteries are arranged in a predetermined number of columns, and
wherein the electrode terminal and the outer surface of the second end of the battery housing of each battery of the plurality of batteries are disposed to face upward.
24. The battery pack according to claim 23 , further comprising:
a plurality of bus bars connecting the plurality of batteries in series and in parallel,
wherein the plurality of bus bars are disposed above the plurality of batteries, and
wherein each bus bar of the plurality of bus bars includes:
a body extending between electrode terminals of adjacent batteries;
a plurality of first bus bar terminals respectively extending in one side direction from the body and electrically coupled to the electrode terminal of the battery located in the one side direction; and
a plurality of second bus bar terminals respectively extending in the other side direction from the body and electrically coupled to the outer surface of the second end of the battery housing of the battery located in the other side direction.
25. A vehicle, comprising at least one battery pack according to claim 22 .
26. An electrode terminal for a battery, comprising:
a body having a top surface, a lower surface and an outer surface extending in an axial direction;
an outer flange extending in a width direction from the outer surface of the body and configured to extend along an outer surface of a bottom of a battery housing;
an inner flange extending from the outer surface of the body, the inner flange being above the outer flange,
wherein the top surface of the body contacts a current collecting unit; and
a recess exposed between the inner flange and the top surface of the body in the width direction.
27. The electrode terminal of claim 26 , wherein the top surface of the body is above the inner flange.
28. The electrode terminal of claim 26 , wherein the top surface of the body is flat.
29. The electrode terminal of claim 26 , wherein the recess has a first surface formed by the outer surface of the body and a second surface formed by an upper surface of the inner flange, and
wherein the first surface and second surface are asymmetrical.
30. The electrode terminal of claim 26 , wherein an angle between the inner flange and the outer flange is between 2° to 60°.
31. The riveting structure of the electrode terminal according to claim 1 , wherein the recess has an acute angle formed by an inner surface of the inner flange portion and a sidewall of the body portion.