A battery cell, a battery, a battery module, a battery pack, and an automobile

Abstract

This utility model provides a battery cell, comprising: a battery cell body extending along a first direction, the interior of which includes a plurality of electrode sheets arranged sequentially along a second direction, the first direction being perpendicular to the second direction; and a tab current-collecting section for collecting and outputting the current generated by the plurality of electrode sheets, including a plurality of tabs, each tab being connected to a plurality of electrode sheets and extending from the ends of the connected electrode sheets along the first direction. The plurality of tabs are joined together as a whole by ultrasonic welding along the second direction, forming a first welding area and a second welding area distributed along the first direction, wherein the first welding area is closer to the battery cell body along the first direction than the second welding area. Using the above technical solution, the shape of the tabs can be precisely fixed, effectively suppressing unexpected bending of the tabs, thereby avoiding short-circuit risks and significantly improving the safety performance of the battery cell. This utility model also provides a battery, a battery module, a battery pack, and a vehicle.

Description

Technical Field

[0001] This utility model belongs to the field of battery technology, specifically relating to a battery cell, a battery, a battery module, a battery pack, and a car. Background Technology

[0002] In recent years, the lithium battery industry has developed rapidly, and its applications have penetrated into numerous fields such as electric vehicles, consumer electronics, energy storage, aerospace, medical equipment, and military security, profoundly impacting all aspects of our lives. At the same time, the safety risks of lithium batteries have increasingly become a focus of attention, with spontaneous combustion being the most worrying safety hazard. The core reason for this safety hazard is the poor shape constraint of the tabs within the battery cell (i.e., insufficient tab structural stability). Although the tabs do not contact the electrode plates during cell manufacturing and short-circuit tests meet standards, if the battery experiences bumps or vibrations during subsequent handling, or if the cell vibrates violently under complex road conditions after assembly into a vehicle, the poorly secured tabs will deform under stress, eventually contacting the cell electrode plates and causing a short circuit. If the short circuit continues, it can eventually lead to a vehicle fire, causing serious personal injury and property damage. Utility Model Content

[0003] The present invention provides the following technical solutions to solve the above-mentioned technical problems.

[0004] This utility model provides a battery cell, comprising:

[0005] The battery cell body extends along a first direction and includes multiple electrode plates arranged sequentially along a second direction, wherein the first direction is perpendicular to the second direction.

[0006] The electrode current collection section is used to collect the current generated by multiple electrodes and output it outward. It includes multiple electrodes, which are respectively connected to the multiple electrodes and extend from the ends of the connected electrodes along the first direction. The multiple electrodes are joined together by ultrasonic welding along the second direction to form a first welding area and a second welding area distributed along the first direction, wherein the first welding area is closer to the cell body along the first direction than the second welding area.

[0007] By employing the above technical solution, the shape of the electrode tab can be precisely fixed, effectively suppressing unintended bending of the electrode tab. This design can effectively prevent the electrode tab from contacting the internal electrode plates of the battery cell due to shape deformation during subsequent circulation processes, and even prevent the electrode tab from embedding into the battery cell body, thereby avoiding the risk of short circuits caused by this and significantly improving the safety performance of the battery cell.

[0008] According to another specific embodiment of the present invention, the width of the first welding area along the first direction is 1mm-2mm.

[0009] According to another specific embodiment of the present invention, along the first direction, the distance between the first welding area and the end of the battery cell body is 2mm-3mm.

[0010] According to another specific embodiment of the present invention, the width of the second welding area along the first direction is 6mm-8mm.

[0011] According to another specific embodiment of the present invention, along the first direction, the distance between the first welding area and the second welding area is 10mm-13mm.

[0012] According to another specific embodiment of the present invention, all of the plurality of tabs are negative tabs, and all of the plurality of electrode sheets are negative electrode sheets.

[0013] This utility model also provides a battery, including a cover plate and a battery cell as described in any of the above embodiments. The cover plate includes a terminal post, and the cover plate is welded to the current collection portion of the terminal tab to output the current collected by the current collection portion of the terminal tab to the outside through the terminal post.

[0014] By adopting the above technical solution, the problem of contact between the electrode tab and the internal electrode sheet of the battery cell caused by the deformation of the electrode tab shape can be effectively avoided, the phenomenon of the electrode tab being embedded in the battery cell body can be eliminated, and the risk of short circuit caused by this can be avoided from the root, thus significantly improving the safety performance of the battery.

[0015] This utility model also provides a battery module, including the battery in the above embodiments.

[0016] By adopting the above technical solution, the problem of contact between the electrode tab and the internal electrode sheet of the battery cell caused by the deformation of the electrode tab shape can be effectively avoided, the phenomenon of the electrode tab being embedded in the battery cell body can be eliminated, and the short circuit risk caused by this can be avoided from the root, thus significantly improving the safety performance of the battery module.

[0017] This utility model also provides a battery pack, including the battery module in the above embodiments.

[0018] By adopting the above technical solution, the problem of contact between the electrode tab and the internal electrode sheet of the battery cell caused by the deformation of the electrode tab shape can be effectively avoided, the phenomenon of the electrode tab being embedded in the battery cell body can be eliminated, and the short circuit risk caused by this can be avoided from the root, thus significantly improving the safety performance of the battery pack.

[0019] This utility model also provides an automobile, including the battery pack described in the above embodiments.

[0020] By adopting the above technical solution, the problem of contact between the electrode tab and the internal electrode sheet of the battery cell caused by the deformation of the electrode tab shape can be effectively avoided, the phenomenon of the electrode tab being embedded in the battery cell body can be eliminated, and the short circuit risk caused by this can be avoided from the root, thus significantly improving the safety performance of the vehicle. Attached Figure Description

[0021] Figure 1 This diagram shows a structural schematic of a battery cell in one embodiment of the present invention where multiple tabs are not ultrasonically welded.

[0022] Figure 2 This is a top view of a battery cell after multiple tabs in the battery cell are ultrasonically welded together to form a whole, according to an embodiment of the present invention.

[0023] Figure 3 This shows a top view of a battery cell after multiple tabs have been ultrasonically welded in a single process using existing technology.

[0024] Figure 4 Showing will Figure 3 The diagram shows the structure of the battery cell and cover plate after assembly.

[0025] Figure 5 Showing will Figure 2 The diagram shows the structure of the battery cell and cover plate after assembly. Detailed Implementation

[0026] The following specific embodiments illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. Although the description of this utility model will be presented in conjunction with preferred embodiments, this does not mean that the features of this utility model are limited to this embodiment. On the contrary, the purpose of describing the utility model in conjunction with the embodiments is to cover other options or modifications that may be derived based on the claims of this utility model. To provide a deep understanding of this utility model, many specific details will be included in the following description. This utility model may also be implemented without using these details. Furthermore, to avoid confusion or obscuring the focus of this utility model, some specific details will be omitted in the description. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of this utility model can be combined with each other.

[0027] The terms “first”, “second”, etc., are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0028] It should be noted that in this specification, similar reference numerals and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0029] To make the objectives, technical solutions, and advantages of this utility model clearer, the embodiments of this utility model will be described in further detail below with reference to the accompanying drawings.

[0030] like Figures 1-2 As shown, this utility model provides a battery cell 1, comprising:

[0031] Battery cell body 2, along the first direction (e.g.) Figures 1-2 Extending in the X direction, its interior includes along a second direction (e.g., Figures 1-2 Multiple electrodes (not shown in the figure) are arranged sequentially in the Y direction, with the first direction X perpendicular to the second direction Y.

[0032] The electrode current collection section 3 is used to collect the current generated by multiple electrodes and output it outward. It includes multiple electrodes 4, which are respectively connected to multiple electrodes and extend from the ends of the electrodes in the first direction X. The multiple electrodes 4 are joined together by ultrasonic welding in the second direction Y to form a whole, and respectively form a first welding area 5 and a second welding area 6 distributed in the first direction X. The first welding area 5 is closer to the cell body 2 in the first direction X than the second welding area 6.

[0033] By employing the above technical solution, multiple tabs 4 are ultrasonically welded twice to form a first welding area 5 and a second welding area 6. The first welding area 5 is closer to the cell body 2 along the first direction X than the second welding area 6. This double welding structure provides a stable fixation effect for the tabs 4, significantly improving the tabs' shape constraint within the cell 1. Compared to the prior art that only uses a single ultrasonic welding (where the ultrasonic welding area 7 is shown in Figure 3, corresponding to the second welding area 6 in this application), this invention, by adding a first welding area 5 closer to the cell body 2, can precisely fix the tab shape and effectively suppress unexpected bending of the tabs. This design effectively prevents the tabs from contacting the internal electrode sheets of the cell due to shape deformation during subsequent handling, and even avoids the tabs embedding into the cell body, thereby effectively eliminating the risk of short circuits and significantly improving the cell's safety performance.

[0034] Furthermore, in the above embodiments, such as Figure 2 As shown, along the first direction X, the width d1 of the first welding area 5 is 1mm-2mm. Controlling the width of the first welding area 5 within this range can both supplement the fixing strength through sufficient welding contact area, ensuring the stability of the electrode tab 4 shape constraint and avoiding poor fixing effect due to excessively narrow welding width, and at the same time, avoid excessive width occupying too much space along the first direction X, which would compress the allocable width of the second welding area 6 and make it too low, thereby affecting the flow stability and structural strength of the second welding area 6.

[0035] Furthermore, in the above embodiments, such as Figure 2 As shown, along the first direction X, the distance d2 between the first welding area 5 and the end of the cell body 2 is 2mm-3mm. This setting, while ensuring the welding constraint effect of the tab 4, can further reduce the risk of the tab 4 contacting the electrode due to shaking, thereby improving the stability and safety of the cell 1.

[0036] Furthermore, in the above embodiments, such as Figure 2 As shown, along the first direction X, the width d4 of the second welding area 6 is 6mm-8mm. This configuration ensures the uniformity and stability of the current flow through sufficient welding area, guaranteeing the conductivity of the electrode current-carrying section and providing reliable support for the cell's efficient current output.

[0037] Furthermore, in the above embodiments, such as Figure 2 As shown, along the first direction X, the distance d3 between the first welding area 5 and the second welding area 6 is 10mm-13mm. This distance setting can form a reasonable buffer distance between the two welding areas, which can avoid the welding stress concentration caused by the distance being too close, thus affecting the shape stability of the tab 4, and also prevent the double welding from weakening the overall constraint ability of the tab due to the distance being too far, ensuring that the overall shape of the tab is controllable when subjected to force or vibration, and further improving the structural reliability.

[0038] Further research shows that when d1 (width of the first welding area) is controlled at 1mm-2mm, d2 (distance between the first welding area and the end of the cell body) is controlled at 2mm-3mm, d3 (distance between the two welding areas) is controlled at 10mm-13mm, and d4 (width of the second welding area) is simultaneously set at 6mm-8mm, the stability of tab 4 reaches its optimal state. X-ray inspection shows that the tab has a regular bending shape and no defects such as contact with the wall, internal insertion, or looseness.

[0039] Meanwhile, this parameter combination significantly improves the first-pass yield of X-ray (an industrial quality inspection method for inspecting the internal tab shape of battery cells) visual inspection. This means that the proportion of products whose tab shape is deemed acceptable (no bending, no contact with the wall, no internal insertion, etc.) after a single X-ray inspection is greatly increased, eliminating the need for repeated inspections and effectively improving inspection efficiency. Practical verification has shown that the tab defect rate (mainly referring to unexpected bending issues) has decreased from 5% to 0%, completely avoiding the short-circuit risk caused by tab bending, thereby greatly improving the safety performance of battery cells and battery modules.

[0040] Furthermore, in the above embodiments, all tabs are negative tabs, and all electrodes are negative electrodes.

[0041] Given that the negative electrode tab is more prone to unexpected bending during production, distribution and use than the positive electrode tab, the above technical solution can specifically address the bending risk of the negative electrode tab, strengthen the internal structural stability of the battery cell by addressing the core risk point, and thus significantly improve the overall safety performance of the battery cell.

[0042] Reference Figure 5 This utility model also provides a battery, including a cover plate 8 and a cell 1 as described in any of the above embodiments. The cover plate 8 includes a terminal post (not shown in the figure), and the cover plate 8 is welded to the electrode tab current-collecting part 3 to output the current collected by the electrode tab current-collecting part 3 to the outside through the terminal post (see reference). Figure 5 (As shown in B in the diagram).

[0043] By adopting the above technical solution, the problem of contact between the tab and the internal electrode sheet of the battery cell caused by the deformation of the tab shape can be effectively avoided, thereby eliminating the phenomenon of the tab being embedded in the battery cell body, and thus eliminating the short circuit risk caused by this at the source, significantly improving the safety performance of the battery. Compared with the structure of the existing technology that is assembled with the cover plate 8 by only a single welding (as shown in A in Figure 4), this utility model forms a stable tab structure through double welding, which can avoid the deformation of the tab due to force and vibration during assembly and subsequent stages, further ensuring the reliability and safety of the overall battery structure.

[0044] This utility model also provides a battery module, including the battery in the above embodiments.

[0045] By adopting the above technical solution, the problem of contact between the electrode tab and the internal electrode sheet of the battery cell caused by the deformation of the electrode tab shape can be effectively avoided, the phenomenon of the electrode tab being embedded in the battery cell body can be eliminated, and the short circuit risk caused by this can be avoided from the root, thus significantly improving the safety performance of the battery module.

[0046] This utility model also provides a battery pack, including the battery module in the above embodiments.

[0047] By adopting the above technical solution, the problem of contact between the electrode tab and the internal electrode sheet of the battery cell caused by the deformation of the electrode tab shape can be effectively avoided, the phenomenon of the electrode tab being embedded in the battery cell body can be eliminated, and the short circuit risk caused by this can be avoided from the root, thus significantly improving the safety performance of the battery pack.

[0048] This utility model also provides an automobile, including the battery pack described in the above embodiments.

[0049] By adopting the above technical solution, the problem of contact between the electrode tab and the internal electrode sheet of the battery cell caused by the deformation of the electrode tab shape can be effectively avoided, the phenomenon of the electrode tab being embedded in the battery cell body can be eliminated, and the short circuit risk caused by this can be avoided from the root, thus significantly improving the safety performance of the vehicle.

[0050] Although the present invention has been illustrated and described with reference to certain preferred embodiments, those skilled in the art should understand that the above description is a further detailed explanation of the present invention in conjunction with specific embodiments, and should not be construed as limiting the specific implementation of the present invention to these descriptions. Those skilled in the art can make various changes in form and detail, including some simple deductions or substitutions, without departing from the spirit and scope of the present invention.

Claims

1. A battery cell, characterized in that, include: The battery cell body extends along a first direction and includes multiple electrode plates arranged sequentially along a second direction, wherein the first direction is perpendicular to the second direction. The electrode current collection section is used to collect the current generated by multiple electrodes and output it outward. It includes multiple electrodes, which are respectively connected to the multiple electrodes and extend from the ends of the connected electrodes along the first direction. The multiple electrodes are joined together by ultrasonic welding along the second direction to form a first welding area and a second welding area distributed along the first direction, wherein the first welding area is closer to the cell body along the first direction than the second welding area.

2. The battery cell according to claim 1, characterized in that, Along the first direction, the width of the first welding area is 1mm-2mm.

3. The battery cell according to claim 1, characterized in that, Along the first direction, the distance between the first welding area and the end of the battery cell body is 2mm-3mm.

4. The battery cell according to claim 1, characterized in that, Along the first direction, the width of the second welding area is 6mm-8mm.

5. The battery cell according to claim 1, characterized in that, Along the first direction, the distance between the first welding area and the second welding area is 10mm-13mm.

6. The battery cell according to claim 1, characterized in that, All of the plurality of tabs are negative tabs, and all of the plurality of electrode plates are negative electrode plates.

7. A battery, characterized in that, The device includes a cover plate and a battery cell according to any one of claims 1-6, wherein the cover plate includes a terminal post, and the cover plate is welded to the electrode busbar to output the current collected by the electrode busbar to the outside through the terminal post.

8. A battery module, characterized in that, Includes the battery as described in claim 7.

9. A battery pack, characterized in that, Includes the battery module as described in claim 8.

10. A car, characterized in that, Includes the battery pack as described in claim 9.

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