Battery welding device and button cell

Abstract

The utility model discloses a battery welding device and button cell relates to battery technical field. The battery welding device is used for welding the pole lug and foil material of button cell, and the battery welding device includes welding head, and the welding area of welding head for welding pole lug and foil material is closed arc or long strip shape, to make the outer edge profile of the welding mark produced by welding head be closed arc or long strip shape, and the maximum width of welding mark is less than the width of pole lug. Since the outer edge profile of welding mark is closed arc or long strip shape, when the welding head deviates, the welding mark deviates and reaches the surface of foil material beyond the pole lug, but since the outer edge profile of welding mark is closed arc or long strip shape, the outer edge of welding mark reaching the surface of foil material does not coincide with the width direction of pole piece, can greatly reduce the harm of welding mark to foil material, and in the process of charging and discharging expansion of battery cell, the foil material is not easy to break at the outer edge of welding mark.

Description

Technical Field

[0001] This utility model belongs to the field of battery technology, and in particular relates to a battery welding device and a button battery. Background Technology

[0002] Current button cells, including steel-cased and pouch cells, typically assemble the positive, negative, and separator components inside the cell by winding them together. The tabs and foil are usually connected by welding, with the weld marks not exceeding the edge of the tabs, and the overall shape of the weld marks being square. This welding method allows for a tight connection between the tabs and the foil, enabling current conduction.

[0003] However, this welding method has risks. When the welding head is offset, the weld mark will extend beyond the edge of the tab and weld onto the foil. The edge of the weld mark may break the foil, and tiny cracks will appear at the weld mark that run through the width of the electrode. When the cell is charged and discharged, the electrode will expand under stress, and the cracks in the width of the electrode will gradually expand, leading to the breakage of the electrode. Utility Model Content

[0004] The technical problem to be solved by this utility model is: to address the problem that micro-cracks appear at the weld mark that penetrate the width of the electrode when the welding head is offset as a whole, and to provide a battery welding device and a button battery.

[0005] To address the aforementioned issues, this utility model provides a battery welding device for welding tabs and foil of a button cell battery. The battery welding device includes a welding head, and the welding area of ​​the welding head for welding the tabs and foil is in the shape of a closed arc or a long strip, so that the outer edge contour of the weld mark produced by the welding head is in the shape of a closed arc or a long strip, and the maximum width of the weld mark is less than the width of the tab.

[0006] As a further improvement to the above technical solution:

[0007] Optionally, the welding area of ​​the welding head is circular, so that the weld mark produced by the welding head is circular; or,

[0008] The welding area of ​​the welding head is elliptical so that the weld mark produced by the welding head is elliptical, and the long axis of the weld mark is consistent with the length direction of the electrode tab.

[0009] Optionally, the welding area of ​​the welding head is elongated, so that the weld mark produced by the welding head is elongated, and the extension direction of the elongated weld mark is consistent with the width direction of the electrode tab.

[0010] Optionally, there are multiple welding areas, which are elongated and spaced apart along the length of the electrode tab; any two welding areas may have the same or different lengths.

[0011] Optionally, the battery welding device is an ultrasonic welding device, a laser welding device, or a resistance welding device.

[0012] On the other hand, this utility model embodiment provides a button cell battery, including a casing and an electrode core. The electrode core includes a tab and a foil. The tab and the foil are welded by a battery welding device as described above. The battery welding device is capable of generating a weld mark in the overlapping area of ​​the tab and the foil. The outer edge contour of the weld mark is a closed arc or a strip, and the maximum width of the outer edge of the weld mark is smaller than the width of the tab.

[0013] As a further improvement to the above technical solution:

[0014] Optionally, the electrode tab is an aluminum electrode tab, a copper electrode tab, or a nickel electrode tab.

[0015] Optionally, the foil material is aluminum foil or copper foil.

[0016] Optionally, the width of the electrode tab is 1 mm to 4 mm.

[0017] Optionally, the overlap length between the tab and the foil is 2 mm to 5 mm.

[0018] The battery welding device and button battery provided in this embodiment of the present invention have at least the following advantages compared with the prior art: when it is necessary to weld the tabs and foil of the button battery, the tabs and foil of the button battery are first stacked, and then the battery welding device is used to generate solder marks in the stacked area of ​​the tabs and foil.

[0019] Because the outer edge of the solder mark is a closed arc or elongated shape, under normal conditions, the solder mark is located in the middle of the tab and the edge of the solder mark does not extend beyond the edge of the tab. However, under abnormal conditions, when the solder head deviates, the solder mark deviates beyond the tab and reaches the surface of the foil. However, because the outer edge of the solder mark is a closed arc or elongated shape, the outer edge of the solder mark that reaches the surface of the foil does not coincide with the width direction of the electrode sheet, which can greatly reduce the damage of the solder mark to the foil. Moreover, during the expansion of the battery cell during charging and discharging, the foil is not easy to break at the outer edge of the solder mark. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments of this utility model will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1This is a schematic diagram of the structure of a button battery provided in one embodiment of the present invention;

[0022] Figure 2 This is a schematic diagram of the structure of a button battery provided in another embodiment of the present invention;

[0023] Figure 3 This is a schematic diagram of the structure of a button battery provided in another embodiment of the present invention.

[0024] The reference numerals in the accompanying drawings are as follows:

[0025] 100. Button cell; 110. Tab; 120. Foil; 130. Solder mark; 140. Cell. Detailed Implementation

[0026] To make the technical problems solved, technical solutions, and beneficial effects of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0027] In the description of this utility model, it should be understood that the terms "longitudinal," "radial," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0028] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0029] One embodiment of this utility model provides a battery welding device, such as... Figures 1 to 3As shown, the battery welding device is used to weld the tabs 110 and foil 120 of the button cell 100. The battery welding device includes a welding head. The welding area of ​​the welding head for welding the tabs 110 and foil 120 is in the shape of a closed arc or a strip, so that the outer edge contour of the weld mark 130 produced by the welding head is in the shape of a closed arc or a strip, and the maximum width of the weld mark 130 is less than the width of the tabs 110.

[0030] When it is necessary to weld the tabs 110 and foil 120 of the button cell 100, the tabs 110 and foil 120 of the button cell 100 are first stacked, and then the battery welding device is used to generate solder marks 130 in the stacked area of ​​the tabs 110 and foil 120.

[0031] Because the outer edge contour of the solder mark 130 is a closed arc or elongated shape, under normal conditions, the solder mark 130 is located in the middle of the tab 110, and the edge of the solder mark 130 does not extend beyond the edge of the tab 110. However, under abnormal conditions, when the solder head deviates, the solder mark 130 deviates beyond the tab 110 and reaches the surface of the foil 120. However, because the outer edge contour of the solder mark 130 is a closed arc or elongated shape, the outer edge of the solder mark 130 reaching the surface of the foil 120 does not coincide with the width direction of the electrode sheet, which can greatly reduce the damage of the solder mark 130 to the foil 120. Moreover, during the charging and discharging expansion of the cell 140, the foil 120 is not easy to break at the outer edge of the solder mark 130.

[0032] In this embodiment, the battery welding device is an ultrasonic welding device. Of course, it is understood that the battery welding device can also be a laser welding device or a resistance welding device, and no limitation is made here.

[0033] In one specific embodiment, such as Figure 1 As shown, the welding area of ​​the welding head is circular so that the weld mark 130 produced by the welding head is circular.

[0034] In another specific embodiment, such as Figure 2 As shown, the welding area of ​​the welding head is elliptical, so that the weld mark 130 produced by the welding head is elliptical, and the long axis of the weld mark 130 is consistent with the length direction of the tab 110.

[0035] In yet another specific embodiment, such as Figure 3 As shown, there are multiple welding zones, which are elongated and spaced apart along the length of the tab 110; any two welding zones may have the same or different lengths.

[0036] In addition, such as Figures 1 to 3As shown, another embodiment of this utility model provides a button cell battery 100, which includes a casing and an electrode core. The electrode core includes a tab 110 and a foil 120. The tab 110 and the foil 120 are welded by a battery welding device as provided in any of the above embodiments. The battery welding device can generate a solder mark 130 in the overlapping area of ​​the tab 110 and the foil 120. The outer edge contour of the solder mark 130 is a closed arc or a strip, and the maximum width of the outer edge of the solder mark 130 is less than the width of the tab 110. The specific structure of the battery welding device is the same as described in the above embodiments. Since this button cell battery 100 adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be described in detail here.

[0037] When it is necessary to weld the tabs 110 and foil 120 of the button cell 100, the tabs 110 and foil 120 of the button cell 100 are first stacked, and then the battery welding device is used to generate solder marks 130 in the stacked area of ​​the tabs 110 and foil 120.

[0038] Because the outer edge contour of the solder mark 130 is a closed arc or elongated shape, under normal conditions, the solder mark 130 is located in the middle of the tab 110, and the edge of the solder mark 130 does not extend beyond the edge of the tab 110. However, under abnormal conditions, when the solder head deviates, the solder mark 130 deviates beyond the tab 110 and reaches the surface of the foil 120. However, because the outer edge contour of the solder mark 130 is a closed arc or elongated shape, the outer edge of the solder mark 130 reaching the surface of the foil 120 does not coincide with the width direction of the electrode sheet, which can greatly reduce the damage of the solder mark 130 to the foil 120. Moreover, during the charging and discharging expansion of the cell 140, the foil 120 is not easy to break at the outer edge of the solder mark 130.

[0039] In this embodiment, the tab 110 is an aluminum tab 110, a copper tab 110, or a nickel tab 110. The foil 120 is an aluminum foil or a copper foil. The width of the tab 110 is typically 1 mm to 4 mm, and the length of the tab 110 overlapping the foil 120 is typically 2 mm to 5 mm. Normally, when the electrode sheet passes through the rollers on an automatic winding machine, the tab 110 and the foil 120 are tightly bonded together at specific locations by the action of the solder head. The solder mark 130 is located in the central area of ​​the tab 110, and the outer edge of the solder mark 130 does not extend beyond the edge of the tab 110, or less than half of the solder mark 130 extends beyond the edge of the tab 110.

[0040] The above-described embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model, and should all be included within the protection scope of this utility model.

Claims

1. A battery welding apparatus for welding the tabs and foil of a button cell battery, characterized in that, The welding head is used to weld the tabs and foil. The welding area of ​​the welding head is in the shape of a closed arc or a strip, so that the outer edge contour of the weld mark produced by the welding head is in the shape of a closed arc or a strip, and the maximum width of the weld mark is less than the width of the tab.

2. The battery welding apparatus according to claim 1, characterized in that, The welding area of ​​the welding head is circular, so that the weld mark produced by the welding head is circular; or, The welding area of ​​the welding head is elliptical so that the weld mark produced by the welding head is elliptical, and the long axis of the weld mark is consistent with the length direction of the electrode tab.

3. The battery welding apparatus according to claim 1, characterized in that, The welding area of ​​the welding head is elongated, so that the weld mark produced by the welding head is elongated, and the extension direction of the elongated weld mark is consistent with the width direction of the electrode tab.

4. The battery welding apparatus according to claim 3, characterized in that, The welding area is provided in multiple ways, and the multiple welding areas are elongated and spaced apart along the length direction of the electrode tab; any two welding areas among the multiple welding areas may have the same or different lengths.

5. The battery welding apparatus according to claim 1, characterized in that, The battery welding device is an ultrasonic welding device, a laser welding device, or a resistance welding device.

6. A button cell battery, characterized in that, The battery includes a housing and an electrode core, the electrode core including tabs and foil, the tabs and the foil being welded by a battery welding apparatus as described in any one of claims 1 to 5, the battery welding apparatus being capable of producing a weld mark in the overlapping area of ​​the tabs and the foil, the outer edge contour of the weld mark being a closed arc or an elongated shape, and the maximum width of the outer edge of the weld mark being less than the width of the tab.

7. The button cell battery according to claim 6, characterized in that, The electrode tab is an aluminum electrode tab, a copper electrode tab, or a nickel electrode tab.

8. The button cell battery according to claim 6, characterized in that, The foil material is aluminum foil or copper foil.

9. The button cell battery according to claim 6, characterized in that, The width of the tab is 1mm to 4mm.

10. The button cell battery according to claim 6, characterized in that, The overlap length between the tab and the foil is 2mm to 5mm.

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