WO2024088219A1

WO2024088219A1 - Tab connection structure and connection method, battery, battery module and electrical device

Info

Publication number: WO2024088219A1
Application number: PCT/CN2023/125992
Authority: WO
Inventors: 陈进强; 赖宏基
Original assignee: 厦门海辰储能科技股份有限公司
Priority date: 2022-10-26
Filing date: 2023-10-23
Publication date: 2024-05-02
Also published as: CN116154413A

Abstract

A tab connection structure, a tab connection method, a battery, a battery module and an electrical device. The tab connection structure comprises: a tab (20) and an adapter piece (30), wherein the adapter piece (30) comprises a tab connection portion (310), and a groove (320) is provided on the tab connection portion (310); and the tab (20) is welded to the tab connection portion (310), a welding mark (50) welded to the tab connection portion (310) is formed on the tab (20), and at least part of an orthographic projection of the welding mark (50) on the adapter piece (30) falls into the groove (320). By means of the tab connection structure, the welding effect of the tab (20) and the adapter piece (30) is improved.

Description

Tab connection structure and connection method, battery, battery module and electrical equipment

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to Chinese Patent Application No. 202211319016.X, filed on October 26, 2022, entitled "Tar Connection Structure and Connection Method, Battery, Battery Module and Electrical Equipment". The contents disclosed in the above-mentioned Chinese patent application are hereby cited in their entirety as part of this application.

Technical Field

The present application relates to the field of energy storage technology, and in particular to a tab connection structure and method, a battery, a battery module and an electrical device.

Background technique

Secondary batteries (such as lithium batteries) have the advantages of high energy density, high power density, many cycles and long storage time. In recent years, they have been widely used in electric vehicles such as electric vehicles and electric bicycles, and large and medium-sized electric equipment such as energy storage facilities.

At present, the electrode assembly in the secondary battery usually includes a pole tab and a switching plate, and the pole tab and the switching plate need to be welded together.

It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present application, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field.

Summary of the invention

A main purpose of the present application is to provide a tab connection structure to improve the welding effect between the tab and the adapter.

In order to achieve the above application purpose, this application adopts the following technical solutions:

According to a first aspect of the present application, a tab connection structure is provided, the tab connection structure comprising:

The adapter plate comprises a tab connection portion, wherein a groove is provided on the tab connection portion;

A pole lug is welded to the pole lug connecting portion, a welding mark formed on the pole lug for welding with the pole lug connecting portion, and the orthographic projection of the welding mark on the adapter sheet at least partially falls into the groove.

According to one embodiment of the present application, the tab completely covers the groove.

According to an embodiment of the present application, the depth of the groove is less than 50% of the thickness of the tab connecting portion.

According to one embodiment of the present application, the tab connection structure further includes:

The protective sheet is arranged on a side of the tab away from the tab connection portion, and at least a portion of the positive projection of the protective sheet on the adapter sheet is located in the groove.

According to one embodiment of the present application, the orthographic projection of the protection sheet on the adapter sheet is located in the groove.

According to an embodiment of the present application, the shape of the protection sheet matches the shape of the groove.

According to one embodiment of the present application, the depth of the groove is greater than 30% of the sum of the thickness of the tab and the protection sheet.

According to an embodiment of the present application, the depth of the groove is less than 50% of the sum of the thickness of the tab and the protection sheet.

According to one embodiment of the present application, the groove includes a bottom surface and a transition surface surrounding the bottom surface, wherein the transition surface connects the bottom surface with the top surface of the pole ear connecting portion; from the edge area of the groove toward the center area, the depth of the groove at the transition surface increases gradually.

According to an embodiment of the present application, the protection sheet includes a first surface and a second surface opposite to each other and a side surface connecting the first surface and the second surface, and the side surface is parallel to the transition surface.

According to a second aspect of the present application, a tab connection method is provided, the tab connection method comprising:

Providing a transfer plate, the transfer plate comprising a tab connection portion, the tab connection portion being provided with a groove;

The pole lug is arranged on the pole lug connecting portion, and the pole lug and the pole lug connecting portion are welded; after welding, a welding mark is formed on the pole lug, and the orthographic projection of the welding mark on the adapter sheet at least partially falls into the groove.

According to one embodiment of the present application, after the tab is disposed on the tab connection portion and before the tab and the tab connection portion are welded, the tab connection method further includes:

A protective sheet is arranged on the side of the pole tab away from the pole tab connecting portion, and the protective sheet, the pole tab and the pole tab connecting portion are welded; after welding, a weld mark is formed on the protective sheet, and at least part of the positive projection of the weld mark on the adapter sheet is located in the groove.

According to a third aspect of the present application, a battery is provided, the battery comprising the above-mentioned tab connection structure.

According to a fourth aspect of the present application, a battery module is provided, the battery module comprising the above-mentioned battery.

According to a fifth aspect of the present application, there is provided an electrical device comprising the above-mentioned battery module.

It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings herein are incorporated into the specification and constitute a part of the specification, illustrate embodiments consistent with the present application, and together with the specification are used to explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

FIG. 1 is a front view of a tab connection structure provided in one embodiment of the present application.

FIG. 2 is a rear view of a tab connection structure provided in one embodiment of the present application.

FIG. 3 is a front view of a tab connection structure provided in another embodiment of the present application.

FIG. 4 is a schematic diagram of an adapter provided in one embodiment of the present application.

FIG. 5 is a top view of an adapter provided in one embodiment of the present application.

FIG. 6 is a schematic diagram of an adapter provided in another embodiment of the present application.

FIG. 7 is a cross-sectional view of a tab connection structure provided in another embodiment of the present application.

FIG. 8 is a flow chart of a tab connection method provided in one embodiment of the present application.

Description of reference numerals:
10. Battery cell body;
20. Earpiece;
30, adapter; 310, pole ear connection portion; 3110, top surface; 320, groove; 3210, bottom surface;
3220, transition surface;
40, protective sheet; 410, first surface; 420, second surface; 430, side surface;
50. Welding mark.

Detailed ways

Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this application will be comprehensive and complete and fully convey the concepts of the example embodiments to those skilled in the art. The same reference numerals in the figures represent the same or similar structures, and thus their detailed description will be omitted.

The embodiments of the present application first provide a pole lug connection structure, as shown in Figures 1, 2, 4 and 5, the pole lug connection structure includes a pole lug 20 and a transfer plate 30, the transfer plate 30 includes a pole lug connection portion 310, and the pole lug connection portion 310 is provided with a groove 320; the pole lug 20 is welded to the pole lug connection portion 310, and a weld mark 50 welded to the pole lug connection portion 310 is formed on the pole lug 20, and the orthographic projection of the weld mark 20 on the transfer plate 30 at least partially falls into the groove 320.

The pole lug connection structure provided in the present application has a groove 320 on the pole lug connection portion 310, and a weld mark 20 is formed after the pole lug 20 is welded to the pole lug connection portion 310. The orthographic projection of the weld mark 20 on the adapter plate 30 at least partially falls into the groove 320, that is, at least part of the groove 320 serves as the welding position between the adapter plate 30 and the pole lug 20. The thickness of the position where the groove 320 is set on the adapter plate 30 is relatively small, which makes it easier to ultrasonically weld the pole lug 20 and the adapter 30, thereby improving the welding effect between the pole lug 20 and the adapter 30.

In one embodiment of the present application, the tab 20 completely covers the groove 320. After the tab 20 is placed above the groove 320, it completely covers the groove 320 to prevent the edge of the tab 20 from being located in the groove 320, so that only the bottom surface of the groove 320 is used as the welding position of the adapter 30 and the tab 20, further making it easier to ultrasonically weld the tab 20 and the adapter 30, thereby improving the welding effect of the tab 20 and the adapter 30.

In one embodiment of the present application, as shown in FIG3 , the tab connection structure further includes: a protective sheet 40. The protective sheet 40 is disposed on the side of the tab 20 away from the tab connection portion 310, and at least part of the positive projection of the protective sheet 40 on the adapter sheet 30 is located in the groove 320. When the tab 20 is ultrasonically welded to the tab connection portion 310 through the protective sheet 40, the tab 20 is first placed above the groove 320, and then the protective sheet 40 is placed above the tab 20, and the protective sheet 40 is slightly aligned with the groove 320, and the tab 20 covers at least part of the groove 320.

At least part of the positive projection of the protective sheet 40 on the adapter sheet 30 is located in the groove 320. When the ultrasonic welding head acts on the protective sheet 40, the bottom of the protective sheet 40 drives at least part of the pole ear 20 to be pressed into the groove 320, thereby improving the sliding dislocation of the protective sheet 40 during welding through the guiding effect of the groove 320; at the same time, the groove 320 also provides a storage space for the pole ear 20 after vibration deformation.

The tab 20 completely covers the groove 320. After the tab 20 is placed above the groove 320, The groove 320 is covered to prevent the edge of the pole tab 20 from being located in the groove 320, that is, the pole tab 20 is completely blocked between the protection sheet 40 and the groove 320, thereby preventing the protection sheet 40 from not being completely pressed on the pole tab 20, thereby improving the reliability of the welding between the pole tab 20 and the pole tab connecting part 310.

Among them, the orthographic projection of the protective sheet 40 on the adapter sheet 30 is located in the groove 320. By making the orthographic projection of the protective sheet 40 on the adapter sheet 30 located in the groove 320, that is, the size of the protective sheet 40 is less than or equal to the size of the groove 320, when the ultrasonic welding head acts on the protective sheet 40, the bottom of the protective sheet 40 drives the tab 20 to be pressed into the groove 320, and the guiding effect of the groove 320 enables the protective sheet 40 to be better located above the groove 320. The protective sheet 40 is guided and limited by the side wall of the groove 320 in the circumferential direction, which further improves the guiding effect of the groove 320 and further improves the sliding dislocation of the protective sheet 40 during welding.

The shape of the protective sheet 40 matches the shape of the groove 320. By matching the shape of the protective sheet 40 with the shape of the groove 320, that is, the shape of the protective sheet 40 is consistent with the shape of the groove 320, after the protective sheet 40 is located above the groove 320 through the guiding effect of the groove 320, the gap between the protective sheet 40 and the side wall of the groove 320 in the circumferential direction can be consistent or substantially consistent, thereby improving the guiding effect of the groove 320, allowing the protective sheet 40 to be completely located in the groove 320, and further improving the sliding dislocation of the protective sheet 40 during welding.

As shown in FIG. 4 and FIG. 5 , the shape of the groove 320 can be a trapezoid, and the shape of the protective sheet 40 can also be a trapezoid. Of course, the shape of the groove 320 can also be a rectangle, a circle, an ellipse, a triangle, a polygon, a circular shape or an irregular shape, and the shape of the protective sheet 40 can match the shape of the groove 320; of course, the shape of the protective sheet 40 and the shape of the groove 320 can also not match, for example, the groove 320 is a trapezoid, and the protective sheet 40 is a rectangle, and the protective sheet 40 can be located on the groove 320 and play the role of a conductor through the groove 320. This application does not limit this, and any changes in the shape of the groove 320 and the protective sheet 40 are within the protection scope of this application.

The depth of the groove 320 is greater than 30% of the sum of the thickness of the tab 20 and the protective sheet 40. By making the depth of the groove 320 greater than 30% of the sum of the thickness of the tab 20 and the protective sheet 40, the groove 320 can provide a space for accommodating the tab 20 after vibration deformation, so as to ensure that the tab 20 is completely pressed into the groove 320, and ensure the stability of the connection structure between the adapter 30 and the tab 20. For example, the depth of the groove 320 is greater than 30%, 35%, 40%, 45%, etc. of the sum of the thickness of the tab 20 and the protective sheet 40, and the present application does not list them one by one here; of course, the depth of the groove 320 can also be less than 30% of the sum of the thickness of the tab 20 and the protective sheet 40, and the present application does not limit this.

The depth of the groove 320 is less than 50% of the sum of the thickness of the tab 20 and the protective sheet 40. The depth of the groove 320 is less than 50% of the sum of the thickness of the tab 20 and the protective sheet 40, so as to prevent the depth of the groove 320 from being too large and reducing the strength of the adapter 30. For example, the depth of the groove 320 is less than 50%, 45%, 40%, 35%, etc. of the sum of the thickness of the tab 20 and the protective sheet 40, which are not listed here in this application; of course, the depth of the groove 320 can also be greater than 50% of the sum of the thickness of the tab 20 and the protective sheet 40, which is not limited in this application.

Among them, by making the depth of the groove 320 greater than 30% of the sum of the thicknesses of the pole ear 20 and the protective sheet 40, and less than 50% of the sum of the thicknesses of the pole ear 20 and the protective sheet 40, the groove 320 can provide a storage space for the pole ear 20 after vibration deformation, so as to ensure that the pole ear 20 is completely pressed into the groove 320 and ensure the stability of the connection structure between the adapter plate 30 and the pole ear 20, and can also prevent the depth of the groove 320 from being too large, thereby reducing the strength of the adapter plate 30.

In the thickness direction of the adapter 30, the depth of the groove 320 is less than 50% of the thickness of the tab connection portion 310. By making the depth of the groove 320 less than 50% of the thickness of the tab connection portion 310, the depth of the groove 320 is prevented from being too large, thereby reducing the strength of the adapter 30. For example, the depth of the groove 320 is less than 50%, 45%, 40%, 35%, etc. of the thickness of the tab connection portion 310, which are not listed one by one in this application; of course, the depth of the groove 320 may also be greater than 50% of the thickness of the tab connection portion 310, which is not limited in this application.

In the thickness direction of the adapter 30, the depth of the groove 320 is greater than 30% of the thickness of the tab connection portion 310. The depth of the groove 320 is greater than 30% of the thickness of the tab connection portion 310. The groove 320 can provide a space for accommodating the tab 20 after vibration deformation, so as to ensure that the tab 20 is completely pressed into the groove 320, and ensure the stability of the connection structure between the adapter 30 and the tab 20. For example, the depth of the groove 320 is greater than 30%, 35%, 40%, 45%, etc. of the thickness of the tab connection portion 310, which are not listed one by one in this application; of course, the depth of the groove 320 can also be less than 30% of the thickness of the tab connection portion 310, which is not limited in this application.

Among them, by making the depth of the groove 320 greater than 30% of the thickness of the pole lug connecting portion 310 and less than 50% of the thickness of the pole lug connecting portion 310, the groove 320 can provide a storage space for the pole lug 20 after vibration deformation, so as to ensure that the pole lug 20 is completely pressed into the groove 320 and ensure the stability of the connection structure between the adapter plate 30 and the pole lug 20, and can also prevent the depth of the groove 320 from being too large to reduce the strength of the adapter plate 30.

In one embodiment of the present application, as shown in FIG6 , the groove 320 includes a bottom surface 3210 and a transition surface 3220 surrounding the bottom surface 3210, and the transition surface 3220 connects the bottom surface 3210 with the top surface 3110 of the tab connection portion 310. The depth of the groove 320 at the transition surface 3220 increases from the edge area of the groove 320 toward the center area.

Specifically, the transition surface 3220 can be regarded as the side wall of the groove 320. The depth of the groove 320 increases from the edge area toward the central area, that is, the side wall of the groove 320 is an inclined surface; by making the depth of the groove 320 at the transition surface 3220 increase from the edge area toward the central area of the groove 320, on the one hand, it can better form a guiding effect on the protective sheet 40, so that when the ultrasonic welding head acts on the protective sheet 40, the protective sheet 40 can be better pressed into the groove 320; on the other hand, the side wall of the groove 320 is an inclined surface, so as to avoid excessive extrusion pressure on the pole ear 20 caused by the opening edge of the groove 320, resulting in tearing of the pole ear 20, thereby improving the reliability of the pole ear connection structure.

Among them, when the groove 320 includes a bottom surface 3210 and a transition surface 3220 surrounding the bottom surface 3210, the transition surface 3220 connects the bottom surface 3210 and the top surface 3110 of the tab connecting portion 310, the depth of the groove 320 described in the above embodiments is the depth at the bottom surface 3210 of the groove 320.

Among them, when the depth of the groove 320 at the transition surface 3220 increases from the edge area of the groove 320 toward the center area, so that the side wall of the groove 320 is a slope, the slope can be an arc surface convex toward the opening periphery of the groove 320, or the slope can be an arc surface concave toward the bottom surface of the groove 320, or the slope can be a continuous uneven slope, and the present application does not impose any restrictions on this.

In one embodiment of the application, as shown in FIG7 , the protective sheet 40 includes a first surface 410 and a second surface 520 facing each other and a side surface 430 connecting the first surface 410 and the second surface 420, and the side surface 430 is parallel to the transition surface 3220 of the groove 320. By making the side surface 430 of the protective sheet 40 parallel to the transition surface 3220 of the groove 320, after the bottom of the protective sheet 40 drives at least part of the tab 20 to be pressed into the groove 320, the pressing effect of the protective sheet 40 on the tab 20 at the transition surface 322 is improved, and the stability of the protective sheet 40 after pressing the tab 20 is improved; at the same time, the side surface 430 of the protective sheet 40 forms a larger surface contact with the tab 20, thereby avoiding the situation where a larger extrusion stress is applied to the tab 20 and cracks in the tab 20, and improving the reliability of welding the tab 20.

Among them, the side surface 430 of the protective sheet 40 and the transition surface 3220 of the groove 320 are parallel or partially parallel in the circumferential direction; of course, the side surface 430 of the protective sheet 40 and the transition surface 3220 of the groove 320 can also be set non-parallel, for example, there is a certain angle between the side surface 430 and the transition surface 3220, such as 5°-15°, and the present application does not impose any restrictions on this.

The side surface 430 of the protective sheet 40 may be formed by connecting two sub-side surfaces with different inclination angles. For example, the sub-side surface connected to the second surface 420 and corresponding to the transition surface 3220 has the same bevel angle as the transition surface 3220, that is, the sub-side surface is parallel to the transition surface 3220; the inclination angle of the sub-side surface not corresponding to the transition surface 3220 may be, for example, 90°, that is, the sub-side surface is perpendicular to the connected first surface 410. Of course, the side surface 430 of the protective sheet 40 may be connected by three, four, five or more sub-side surfaces with different inclination angles. It is sufficient to ensure that the sub-side surface corresponding to the transition surface 3220 is parallel to the transition surface 3220, and this application does not impose any limitation on this.

In one embodiment of the present application, a chamfer may be provided on the opening edge of the groove 320, that is, a chamfer is provided at the connection between the transition surface 3220 of the groove 320 and the top surface 3110 of the tab connection portion 310, and the chamfer surface is a plane or an arc surface. By providing a chamfer on the opening edge of the groove 320, it is avoided that the opening edge of the groove 320 causes excessive extrusion pressure on the tab 20, resulting in tearing of the tab 20, thereby improving the reliability of the tab connection structure.

Among them, chamfers can be formed on the circumference of the opening edge of the groove 320, that is, a continuous circle of chamfered surfaces is formed on the opening edge of the groove 320, so as to further avoid the situation where the opening edge of the groove 320 exerts too much pressure on the tab 20, resulting in the tab 20 being torn. Of course, chamfers can also be set on the opening edges of some grooves 320, and this application does not limit this.

The embodiment of the present application further provides a tab connection method, as shown in FIG8 , the tab connection method includes:

Step S100, providing a transfer plate, wherein the transfer plate comprises a tab connection portion, and a groove is provided on the tab connection portion;

Step S200, placing the electrode tab on the electrode tab connecting portion, and welding the electrode tab and the electrode tab connecting portion; after welding, a welding mark is formed on the electrode tab, and the orthographic projection of the welding mark on the adapter sheet at least partially falls into the groove.

The pole lug connection method provided in the present application is provided with a groove on the pole lug connection part. When the pole lug is welded to the pole lug connection part, the positive projection of the weld mark on the pole lug on the adapter sheet at least partially falls into the groove, that is, at least part of the groove serves as the welding position between the adapter sheet and the pole lug. The thickness of the position where the groove is set on the adapter sheet is relatively small, which makes it easier to ultrasonically weld the pole lug and the adapter, thereby improving the welding effect between the pole lug and the adapter.

In one embodiment of the present application, after the pole ear is arranged on the pole ear connection part and before the pole ear and the pole ear connection part are welded, the pole ear connection method further includes: arranging a protective sheet on the side of the pole ear away from the pole ear connection part, welding the protective sheet, the pole ear and the pole ear connection part; after welding, a weld mark is formed on the protective sheet, and at least part of the positive projection of the weld mark on the adapter sheet is located in the groove. When the pole ear is ultrasonically welded to the pole ear connection part through the protective sheet, the pole ear is first placed above the groove, and then the protective sheet is placed above the pole ear, and the protective sheet is slightly aligned with the groove, the pole ear covers at least part of the groove, and at least part of the positive projection of the protective sheet on the adapter sheet is located in the groove, when the ultrasonic welding head acts on the protective sheet, the bottom of the protective sheet drives at least part of the pole ear to be pressed into the groove, thereby improving the sliding dislocation of the protective sheet during welding through the guiding effect of the groove.

In the embodiment of the tab connection method provided in the present application, for other details and technical effects of welding the tab to the adapter, please refer to the detailed discussion in the above embodiment of the tab connection structure, and the embodiment of the method will not be repeated here.

The embodiment of the present application also provides a battery, which includes the above-mentioned tab connection structure. Specifically, as shown in FIG1 , the battery includes two cells, and the two cells respectively include a cell body 10 and a tab 20 connected to the cell body 10. The positive tabs of the two cells are connected together through the above-mentioned tab connection structure, thereby connecting to the positive pole of the battery through the pole connection part; the negative tabs of the two cells are connected together through the above-mentioned tab connection structure, thereby connecting to the negative pole of the battery through the pole connection part; the battery can be a lithium-ion battery.

The battery provided by the present application has a groove on the tab connection portion of the adapter. After the tab is welded to the tab connection portion, the orthographic projection of the welding mark on the tab on the adapter at least partially falls into the groove, that is, at least part of the groove serves as the welding position of the adapter and the tab. The thickness of the position where the groove is set on the adapter is relatively small, which makes it easier to ultrasonically weld the tab and the adapter, thereby improving the welding effect of the tab and the adapter. The reliability of the battery is improved.

For more details and beneficial effects of the battery of the present application, please refer to the above discussion on the embodiment of the tab connection structure, which will not be repeated here.

The embodiment of the present application also provides a battery module, which includes the above-mentioned battery, and the battery module is, for example, a battery pack. In the battery module provided by the present application, a groove is provided on the pole ear connection portion of the adapter of the battery, and after the pole ear is welded to the pole ear connection portion, the positive projection of the weld mark on the pole ear on the adapter at least partially falls into the groove, that is, at least part of the groove serves as the welding position of the adapter and the pole ear, and the thickness of the position where the groove is set on the adapter is relatively small, which makes it easier to ultrasonically weld the pole ear and the adapter, thereby improving the welding effect of the pole ear and the adapter and improving the reliability of the battery module.

For more details and beneficial effects of the battery module of the present application, please refer to the above discussion on the embodiment of the tab connection structure, which will not be repeated here.

The embodiment of the present application also provides an electric device, which includes the above-mentioned battery module, and the electric device is, for example, a vehicle or an energy storage device. In the electric device provided by the present application, a groove is provided on the pole ear connection portion of the adapter of the battery, and after the pole ear is welded to the pole ear connection portion, the positive projection of the weld mark on the pole ear on the adapter at least partially falls into the groove, that is, at least part of the groove serves as the welding position between the adapter and the pole ear, and the thickness of the position where the groove is set on the adapter is relatively small, which makes it easier to ultrasonically weld the pole ear and the adapter, thereby improving the welding effect of the pole ear and the adapter, thereby improving the reliability of the electric device.

For more details and beneficial effects of the electrical equipment of the present application, please refer to the above discussion on the embodiment of the pole ear connection structure, which will not be repeated here.

In the application examples, the term "plurality" refers to two or more than two, unless otherwise clearly defined. The terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; "connected" can be a direct connection or an indirect connection through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the application examples can be understood according to the specific circumstances.

In the description of the application embodiments, it is necessary to understand that the terms "upper", "lower", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the application embodiments and simplifying the description, rather than indicating or implying that the device or unit referred to must have a specific direction, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the application embodiments.

In the description of this specification, the description of the term "an embodiment" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the application embodiment. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

The above are only preferred embodiments of the application embodiments and are not intended to limit the application embodiments. For those skilled in the art, the application embodiments may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the application embodiments shall be included in the protection scope of the application embodiments.

Claims

A tab connection structure, comprising:

The adapter plate comprises a tab connection portion, wherein a groove is provided on the tab connection portion;

A pole lug is welded to the pole lug connecting portion, a welding mark formed on the pole lug for welding with the pole lug connecting portion, and the orthographic projection of the welding mark on the adapter sheet at least partially falls into the groove.
The tab connection structure according to claim 1, wherein the tab completely covers the groove.
The tab connection structure according to claim 1, wherein the depth of the groove is less than 50% of the thickness of the tab connection portion.
The tab connection structure according to claim 1, wherein the tab connection structure further comprises:

The protective sheet is arranged on a side of the tab away from the tab connection portion, and at least a portion of the positive projection of the protective sheet on the adapter sheet is located in the groove.
The tab connection structure according to claim 1 or 4, wherein the orthographic projection of the protective sheet on the adapter sheet is located in the groove.
The tab connection structure according to claim 5, wherein the shape of the protection sheet matches the shape of the groove.
The tab connection structure according to claim 4, wherein the depth of the groove is greater than 30% of the sum of the thickness of the tab and the protective sheet.
The pole lug connection structure according to claim 4 or 7, wherein the depth of the groove is less than 50% of the sum of the thickness of the pole lug and the protective sheet.
The pole lug connection structure according to claim 4, wherein the groove comprises a bottom surface and a transition surface surrounding the bottom surface, the transition surface connecting the bottom surface with the top surface of the pole lug connection portion; and the depth of the groove at the transition surface increases from the edge area of the groove toward the center area.
The tab connection structure according to claim 9, wherein the protection sheet comprises a first surface and a second surface opposite to each other and a side surface connecting the first surface and the second surface, and the side surface is parallel to the transition surface.
A tab connection method, comprising:

Providing a transfer plate, the transfer plate comprising a tab connection portion, the tab connection portion being provided with a groove;

The pole lug is arranged on the pole lug connecting portion, and the pole lug and the pole lug connecting portion are welded; after welding, A welding mark is formed on the pole ear, and the orthographic projection of the welding mark on the adapter sheet at least partially falls into the groove.
The tab connection method according to claim 11, wherein after the tab is disposed on the tab connection portion and before the tab and the tab connection portion are welded, the tab connection method further comprises:

A protective sheet is arranged on the side of the pole tab away from the pole tab connecting portion, and the protective sheet, the pole tab and the pole tab connecting portion are welded; after welding, a weld mark is formed on the protective sheet, and at least part of the positive projection of the weld mark on the adapter sheet is located in the groove.
A battery comprising the tab connection structure according to any one of claims 1 to 10.
A battery module comprising the battery according to claim 13.
An electrical device comprising the battery module according to claim 14.