Tab shaping method and battery assembly

Abstract

This invention provides a method for shaping electrode tabs and a battery assembly. The electrode tab shaping method includes: after welding the electrode tab to the adapter plate, performing a positioning operation, placing the positioning member on the adapter plate from above, and adjusting the position of the positioning member so that at least a portion of the positioning member covers the welded portion between the electrode tab and the adapter plate; performing a cell assembly operation, during which the portion of the electrode tab not covered by the positioning member bends around the end of the positioning member as the cell moves. This invention solves the problem in the prior art where the electrode tab is easily deformed and inserted backwards into the cell during the battery assembly process.

Description

Technical Field

[0001] This invention relates to the field of battery technology, and more specifically, to a method for shaping electrode tabs and a battery assembly. Background Technology

[0002] In existing secondary batteries, after ultrasonic welding of the tabs and laser welding of the soft connection, the core is assembled. During this process, because the adapter is hard and the tab is soft, the adapter will cause the tab to deform randomly and disorderly in the space between the cell body and the cover plate. When the tab penetrates into the cell body during the deformation process and forms an "inverted insertion", if the negative tab penetrates and contacts the positive electrode, or the positive tab penetrates and contacts the negative electrode, it will cause a short circuit and affect the battery safety.

[0003] When designing battery structures, engineers aim to guide the tabs to deform along a predetermined path using the adapter tabs. Generally, in designs with tabs on both sides, plastic spacers can be added between the cell and the cover plate to shape the tabs. However, in designs with dual tabs on the same side, the spatial structure and mechanical movements during cell assembly prevent the use of plastic spacers to shape the tabs.

[0004] Therefore, existing technologies have the problem that the tabs are easily deformed and inserted upside down into the battery cell during the battery cell assembly process. Summary of the Invention

[0005] The main objective of this invention is to provide a method for shaping electrode tabs and a battery assembly to solve the problem in the prior art where electrode tabs are easily deformed and inserted backwards into the battery cell during the battery cell assembly process.

[0006] To achieve the above objectives, according to one aspect of the present invention, a method for shaping an electrode tab is provided, comprising: after welding the electrode tab to an adapter piece, performing an operation of placing a limiting member, wherein the limiting member is placed on the adapter piece from above, and adjusting the position of the limiting member so that at least a portion of the limiting member covers the portion of the electrode tab welded to the adapter piece; performing a core-combining operation on the battery cell, wherein during the core-combining operation, the portion of the electrode tab not covered by the limiting member bends around the end of the limiting member during the movement of the battery cell.

[0007] Furthermore, at least a portion of the limiting member is made of a deformable material. During the core-closing operation, the limiting member is heated to deform it along a preset direction so that the end of the deformed limiting member provides limiting support for the electrode tab.

[0008] Furthermore, during the heating process of the limiting component, the end region of the limiting component corresponding to the welding position of the electrode tab and the adapter plate deforms along a preset direction.

[0009] Furthermore, the tab shaping method also includes the step of selecting a deformation material. In the process of selecting the deformation material, shape memory ceramic material or shape memory alloy material is selected as the deformation material; and when shape memory alloy material is selected as the deformation material, a limiting component with an insulating coating on its surface is selected.

[0010] Furthermore, the insulating coating is a Teflon coating.

[0011] Furthermore, in the process of selecting deformation materials, a one-way shape memory effect material is selected as the deformation material based on the battery's highest operating temperature T2; wherein, the deformation temperature T1 of the one-way shape memory effect material is greater than the battery's highest operating temperature T2.

[0012] Furthermore, in the process of selecting deformation materials, based on the battery's highest operating temperature T5 and lowest operating temperature T6, a two-way shape memory effect material is selected as the deformation material; wherein, the deformation temperature T3 and the recovery temperature T4 of the two-way shape memory effect material need to satisfy: T3 is greater than T5, and T4 is less than T6.

[0013] According to another aspect of the present invention, a battery assembly is provided, the battery assembly being manufactured by the above-described tab shaping method, the battery assembly comprising: a cover plate assembly; an adapter piece disposed on the cover plate assembly; a tab, the tab being welded to the adapter piece; and a limiting member disposed on the adapter piece, the portion of the tab welded to the adapter piece being located between the adapter piece and the limiting member, and the limiting member having a deformation structure corresponding to the portion of the tab welded to the adapter piece.

[0014] Furthermore, the deformable structure is bent and formed and includes a first segment and a second segment that are connected to each other. There is a deformation angle between the first segment and the second segment. When the temperature of the deformable structure rises to a preset temperature, the deformation angle increases.

[0015] Furthermore, the cover assembly includes a top cover and a plastic ring arranged around the periphery of the top cover. The adapter piece and the limiting member are both located within the space enclosed by the plastic ring. In the thickness direction of the adapter piece, the distance H from the end of the plastic ring away from the top cover where the adapter piece is welded to the electrode tab is greater than the distance h from the end of the second segment away from the first segment to the electrode tab; and / or in the radial direction of the plastic ring, the distance d from the connection point of the first segment and the second segment to the inner wall of the plastic ring is the distance D1 from the end of the adapter piece to the inner wall of the plastic ring is the distance D2 from the welded part of the electrode tab to the inner wall of the plastic ring, and d < D1 < D2.

[0016] Applying the technical solution of this invention, the tab shaping method in this application includes: after the tab is welded to the adapter piece, performing the operation of placing a limiting member, the limiting member is placed on the adapter piece from above, and the position of the limiting member is adjusted so that at least part of the limiting member covers the part of the tab welded to the adapter piece; performing a core-combining operation on the battery cell, during the core-combining operation, the part of the tab not covered by the limiting member bends around the end of the limiting member during the movement of the battery cell.

[0017] When using the tab shaping method of this application to assemble battery cells, a limiting member is installed on the adapter after the tab and adapter piece are welded together. This limiting member covers the welded portion of the tab and adapter piece, ensuring that during cell assembly, the limiting member can restrict other parts of the tab and allow the tab to bend around the end of the limiting member. This effectively prevents the tab from being inserted backwards into the cell, thus improving battery safety. Therefore, the tab shaping method of this application effectively solves the problem in the prior art where the tab easily deforms and is inserted backwards into the cell during battery assembly. Attached Figure Description

[0018] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0019] Figure 1 A flowchart illustrating a specific embodiment of the electrode shaping method of this application is shown;

[0020] Figure 2 This invention provides a schematic diagram of the structure of a battery assembly before core assembly, according to a specific embodiment of the present application.

[0021] Figure 3 This illustration shows the positional relationship between the tabs and the limiting member of a battery assembly before core assembly, according to a specific embodiment of this application.

[0022] Figure 4 This diagram illustrates the positional relationship between the tabs and the limiting member of a battery assembly after core bonding, according to a specific embodiment of this application.

[0023] The above figures include the following reference numerals:

[0024] 10. Electrode tab; 20. Adapter plate; 30. Limiting component; 31. Deformation structure; 311. First section; 312. Second section; 40. Battery cell; 50. Cover plate assembly; 51. Top cover; 52. Plastic ring. Detailed Implementation

[0025] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0026] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0027] In this invention, unless otherwise stated, directional terms such as "upper," "lower," "top," and "bottom" are generally used in relation to the direction shown in the accompanying drawings, or in relation to the vertical, perpendicular, or gravitational direction of the component itself; similarly, for ease of understanding and description, "inner" and "outer" refer to the inner and outer contours of each component itself, but the above directional terms are not intended to limit this invention.

[0028] To address the problem in the prior art that the tab 10 is easily deformed and inserted backwards into the cell 40 during the battery assembly process, this application provides a tab shaping method and a battery assembly.

[0029] The tab shaping method in this application includes: after the tab 10 is welded to the adapter piece 20, performing the operation of placing a limiting member 30, the limiting member 30 is placed on the adapter piece 20 from above, and the position of the limiting member 30 is adjusted so that at least part of the limiting member 30 covers the part of the tab 10 and the adapter piece 20 that is welded; performing a core-combining operation on the battery cell 40, during the core-combining operation, the part of the tab 10 not covered by the limiting member 30 bends around the end of the limiting member 30 during the movement of the battery cell 40.

[0030] When using the tab shaping method of this application to assemble the battery cell 40, after the tab 10 and the adapter piece 20 are welded, a limiting member 30 is set on the adapter piece 20, and the limiting member 30 can cover the part where the tab 10 and the adapter piece 20 are welded. This ensures that during the assembly process of the battery cell 40, the limiting member 30 can limit other parts of the tab 10 and ensure that the tab 10 can bend around the end of the limiting member 30, thereby effectively preventing the tab 10 from being inserted backwards into the battery cell 40, thus improving the battery's safety performance. Therefore, the tab shaping method of this application effectively solves the problem in the prior art that the tab 10 is easily deformed and inserted backwards into the battery cell 40 during the battery assembly process.

[0031] In this application, the battery cell assembly operation involves precisely stacking, aligning, and combining multiple individual battery cells 40 or battery cell 40 units into a complete battery cell 40 assembly according to design requirements, in preparation for subsequent packaging. Furthermore, in this application, the limiting member 30 and the adapter piece 20 can be connected by methods such as adhesive bonding, riveting, or welding.

[0032] During the welding process between the tab 10 and the adapter piece 20, the tab 10 of the battery cell 40 is welded to the adapter piece 20 by ultrasonic welding, soft connection laser welding and other methods.

[0033] In one specific embodiment of this application, at least a portion of the limiting member 30 is made of a deformable material. During the core-joining operation, the limiting member 30 is heated to deform it along a preset direction, so that the end of the deformed limiting member 30 provides limiting support for the tab 10. That is, in this application, after the ultrasonic welding and soft connection laser welding processes of the tab 10 are completed and before the core-joining process begins, a deformable material with thermo-deformable properties is provided above the side where the adapter piece 20 and the tab 10 are welded. The deformable material deforms according to a preset shape under subsequent heating, thereby providing a guiding path for the bending of the tab 10 during the core-joining process, so as to prevent the tab 10 from bending towards the battery cell 40 and being inserted upside down into the battery cell 40.

[0034] Preferably, in this application, the limiting member 30 is made of a thermoplastic material, meaning that during the core-combining operation, when the limiting member 30 is heated, it can deform. Simultaneously, since the deformation of the limiting member 30 occurs concurrently with the core-combining operation, it can dynamically guide the tab 10 during this deformation. In other words, when the portion of the tab 10 not covered by the limiting member 30 bends around the end of the limiting member 30 during the movement of the battery cell 40, the tab 10 actually moves along with the deformed portion of the limiting member 30. This allows the limiting member 30 to stretch the tab to a certain extent, or in other words, the tab can bend around the limiting member during this process, thus causing the portion of the tab that originally tended to move towards the battery cell to move away from the battery cell.

[0035] Therefore, in this application, the limiting member 30 can not only effectively prevent the tab 10 from bending towards the cell 40 and being inserted upside down into the cell 40, but also play a certain shaping role for the tab.

[0036] Optionally, during the heating process of the limiting member 30, the end region of the limiting member 30 corresponding to the welding position between the tab 10 and the adapter piece 20 deforms along a preset direction. With this configuration, when the limiting member 30 is heated, this region of the limiting member 30 can actively bend along the preset direction, forming a guiding structure for the tab 10. This forces the tab 10 to bend along a preset path during the core-fitting process, preventing the tab 10 from randomly folding, tilting, or being inserted backwards into the cell 40 body due to the rigid tension of the adapter piece 20. This fundamentally eliminates the risk of short circuits between the positive and negative electrodes, significantly improving battery safety performance. Furthermore, in this application, the limiting member 30 deforms or bends in a direction away from the adapter piece 20. Of course, the preset direction in this application can also be other directions, as long as the limiting member 30 can prevent the tab 10 from being inserted backwards into the cell 40.

[0037] Optionally, the tab shaping method further includes a step of selecting a deformation material. In selecting the deformation material, shape memory ceramic material or shape memory alloy material is selected as the deformation material. When selecting a shape memory alloy material as the deformation material, a limiting member 30 with an insulating coating on its surface is selected to ensure the insulating effect of the limiting member 30. Furthermore, in this application, the limiting member 30 also needs to possess a certain degree of corrosion resistance.

[0038] Preferably, the insulating coating is a Teflon coating. Of course, other coatings can also be used as the insulating coating in this application, as long as the limiting member 30 has insulating properties.

[0039] Optionally, in the process of selecting deformation materials, a one-way shape memory effect material is selected as the deformation material based on the battery's highest operating temperature T2; wherein, the deformation temperature T1 of the one-way shape memory effect material is greater than the battery's highest operating temperature T2.

[0040] Optionally, in the process of selecting deformation materials, a two-way shape memory effect material is selected as the deformation material based on the battery's highest operating temperature T5 and the battery's lowest operating temperature T6; wherein, the deformation temperature T3 and the recovery temperature T4 of the two-way shape memory effect material need to satisfy: T3 is greater than T5 and T4 is less than T6.

[0041] With this design, the material remains in a "cold stable state" under normal battery charging and discharging conditions and high-temperature environments, preventing unexpected deformation due to ambient temperature fluctuations. This fundamentally avoids the risk of the material "self-restoring its original shape" during use, which could cause the tab 10 to spring back, loosen, and contact the main body of the cell 40, leading to internal short circuits, thermal runaway, or even fire and explosion. This significantly improves the safety redundancy of the battery throughout its entire life cycle.

[0042] like Figure 1 As shown, in a specific embodiment of this application, the main steps of the electrode tab shaping method include: S1: after laser welding of the soft connection, the battery cell is transferred to the core-combining station; S2: after the battery cell is positioned, a deformation material is set and fixed; S3: the flipping cylinder flips, driving the battery cells on both sides to combine; S4: heat is applied to the deformation material to deform it into a preset shape; S5: during the core-combining process, the electrode tab is bent along the set path of the deformation material for shaping.

[0043] According to another aspect of the invention, such as Figures 2 to 4As shown, a battery assembly is provided, which is manufactured by the above-described tab shaping method. The battery assembly includes a cover plate assembly 50, an adapter piece 20, tabs 10, and a limiting member 30. The adapter piece 20 is disposed on the cover plate assembly 50; the tabs 10 are welded to the adapter piece 20; the limiting member 30 is disposed on the adapter piece 20, and the portion of the tabs 10 welded to the adapter piece 20 is located between the adapter piece 20 and the limiting member 30, and the limiting member 30 is provided with a deformation structure 31 corresponding to the portion of the tabs 10 welded to the adapter piece 20.

[0044] Specifically, the deformable structure 31 is bent and includes a first segment 311 and a second segment 312 that are connected to each other. There is a deformation angle between the first segment 311 and the second segment 312. When the temperature of the deformable structure 31 rises to a preset temperature, the deformation angle increases. That is to say, in this embodiment, when the limiting member 30 deforms along a preset direction, the deformation angle of the deformable structure 31 is larger.

[0045] Specifically, the cover plate assembly 50 includes a top cover 51 and a plastic ring 52 arranged around the periphery of the top cover 51. The adapter piece 20 and the limiting member 30 are both located within the space enclosed by the plastic ring 52. In the thickness direction of the adapter piece 20, the distance H from the end of the plastic ring 52 away from the top cover 51 to the part of the adapter piece 20 welded to the tab 10 is greater than the distance h from the end of the second segment 312 away from the first segment 311 to the tab 10. In the radial direction of the plastic ring 52, the distance d from the connection point of the first segment 311 and the second segment 312 to the inner wall of the plastic ring 52 is d, the distance D1 from the end of the adapter piece 20 to the inner wall of the plastic ring 52 is D1, and the distance D2 from the part of the tab 10 welded to the adapter piece 20 to the inner wall of the plastic ring 52 is D2, and d < D1 < D2. In this application, by setting H > h in the thickness direction, that is, the distance from the end face of the plastic ring 52 away from the top cover 51 to the welding point of the adapter piece 20 is greater than the distance from the end of the second segment 312 of the limiting member 30 away from the first segment 311 to the tab 10, it is ensured that when the limiting member 30 is deformed by heat, its deformed end will not touch the plastic ring 52 or the cell 40, leaving sufficient space for deformation and ensuring the performance of the battery. At the same time, by limiting d < D1 < D2, the limiting effect of the limiting member 30 on the tab 10 can be effectively guaranteed, thereby effectively limiting the deformation direction or the shape after deformation of the tab 10, so as to prevent the tab 10 from being inserted into the cell 40 after disordered deformation.

[0046] Of course, in this application, the distance d from the connection point of the first segment 311 and the second segment 312 to the inner wall of the plastic ring 52 needs to be greater than 0, that is, a certain space needs to be reserved between the connection point of the first segment 311 and the second segment 312 and the inner wall of the plastic ring 52, so as to provide movement space for the tab 10.

[0047] As can be seen from the above description, the embodiments of the present invention achieve the following technical effects:

[0048] 1. Effectively solves the problem in the existing technology that the tab 10 is easily deformed and inserted backwards into the cell 40 during the battery cell assembly process;

[0049] 2. Ensures the safety of battery use.

[0050] Obviously, the embodiments described above are merely some, not all, embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort should fall within the scope of protection of the present invention.

[0051] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0052] It should be noted that the terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in sequences other than those illustrated or described herein.

[0053] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for shaping the electrode ear, characterized in that, include: After the tab (10) is welded to the adapter piece (20), the operation of placing the limiting member (30) is performed. The limiting member (30) is placed on the adapter piece (20) from above, and the position of the limiting member (30) is adjusted so that at least part of the limiting member (30) covers the part of the tab (10) and the adapter piece (20) that are welded together. When the battery cell (40) is closed, during the closing operation, the part of the tab (10) that is not covered by the limiting member (30) bends around the end of the limiting member (30) as the battery cell (40) moves.

2. The electrode ear shaping method according to claim 1, characterized in that, At least a portion of the limiting member (30) is made of a deformable material. During the core-closing operation, the limiting member (30) is heated to deform the limiting member (30) in a preset direction so that the end of the deformed limiting member (30) provides limiting support for the tab (10).

3. The electrode ear shaping method according to claim 2, characterized in that, During the heating process of the limiting member (30), the end area of ​​the limiting member (30) corresponding to the welding position of the electrode (10) and the adapter piece (20) deforms in a preset direction.

4. The electrode ear shaping method according to claim 2, characterized in that, The electrode shaping method further includes a step of selecting a deformable material. During the selection of the deformable material... Shape memory ceramic materials or shape memory alloy materials are selected as the deformation materials; Furthermore, when the shape memory alloy material is selected as the deformation material, the limiting member (30) with an insulating coating on its surface is selected.

5. The electrode ear shaping method according to claim 4, characterized in that, The insulating coating is a Teflon coating.

6. The electrode ear shaping method according to claim 4, characterized in that, In the process of selecting the deformable material Based on the battery's highest operating temperature T2, a single-pass shape memory effect material is selected as the deformation material. The deformation temperature T1 of the single-pass shape memory effect material is greater than the maximum operating temperature T2 of the battery.

7. The method for shaping the electrode ear according to claim 4, characterized in that, In the process of selecting the deformable material Based on the battery's highest operating temperature T5 and the battery's lowest operating temperature T6, a two-way shape memory effect material is selected as the deformation material. The deformation temperature T3 and the recovery temperature T4 of the two-way shape memory effect material need to satisfy the following conditions: T3 is greater than T5 and T4 is less than T6.

8. A battery assembly, characterized in that, The battery assembly is manufactured by the tab shaping method according to any one of claims 1 to 7, the battery assembly comprising: Cover plate assembly (50); Adapter piece (20), the adapter piece (20) is disposed on the cover plate assembly (50); Electrode (10), wherein the electrode (10) is welded to the adapter piece (20); A limiting member (30) is provided on the adapter piece (20). The portion of the electrode tab (10) welded to the adapter piece (20) is located between the adapter piece (20) and the limiting member (30). The limiting member (30) is provided with a deformation structure (31) corresponding to the portion of the electrode tab (10) welded to the adapter piece (20).

9. The battery assembly according to claim 8, characterized in that, The deformable structure (31) is bent and includes a first segment (311) and a second segment (312) connected to each other. There is a deformation angle between the first segment (311) and the second segment (312). When the temperature of the deformable structure (31) rises to a preset temperature, the deformation angle increases.

10. The battery assembly according to claim 9, characterized in that, The cover assembly (50) includes a top cover (51) and a plastic ring (52) arranged around the periphery of the top cover (51). The adapter piece (20) and the limiting member (30) are both located within the space enclosed by the plastic ring (52). In the thickness direction of the adapter piece (20), the distance H from the portion of the adapter piece (20) welded to the tab (10) to the end of the plastic ring (52) away from the top cover (51) is greater than the distance h from the end of the second segment (312) away from the first segment (311) to the tab (10); and / or In the radial direction of the plastic ring (52), the distance from the connection point of the first segment (311) and the second segment (312) to the inner wall of the plastic ring (52) is d, the distance from the end of the adapter piece (20) to the inner wall of the plastic ring (52) is D1, and the distance from the welded part of the electrode tab (10) and the adapter piece (20) to the inner wall of the plastic ring (52) is D2, and d < D1 < D2.

Images