Winding type battery cell pre-rolling clamp

Abstract

The utility model belongs to the technical field of clamps, and mainly relates to a pre-rolling clamp for a winding type battery cell, which is suitable for the winding type battery cell, the winding type battery cell is provided with tabs, the pre-rolling clamp for the winding type battery cell is provided with a plurality of first guide grooves and / or a plurality of second guide grooves for the tabs to be inserted, and the second guide grooves are positioned at the peripheries of all the first guide grooves; from top to bottom, the diameter of the first guide groove is increased, and / or the diameter of the second guide groove is decreased; through the design, the clamp disclosed by the utility model can be used for pre-collecting an outer-ring tab and pre-pressing an inner-ring tab of the winding type battery cell, so that the inner-ring tab and the outer-ring tab of the winding type battery cell are respectively and orderly folded towards the inside of the winding cell and the outside of a central hole, and the tabs cannot be turned outwards and inserted inwards during kneading.

Description

Technical Field

[0001] This utility model belongs to the field of clamping technology, and mainly relates to a battery cell pre-kneading clamp. Background Technology

[0002] Lithium-ion batteries have become an indispensable part of modern society due to their superior performance and wide range of applications. They play a crucial role in many fields, including communication equipment, energy storage systems, clean energy technologies, and transportation. Furthermore, the high energy density, long lifespan, and rapid charge / discharge capabilities of lithium-ion batteries make them the preferred power solution in these sectors.

[0003] In recent years, tabless or full-tab battery structures have gradually become the mainstream trend in the industry. This design significantly improves the battery's conductivity and thermal management capabilities by eliminating the tabs in traditional batteries or extending them to the entire electrode surface. However, in the design of tabless structures, the tabs need to be flattened (kneaded) due to the need to consider quality factors. During the flattening process, it is extremely easy for the tabs to fold outward or dent inward, further puncturing the separator and causing a short circuit failure between the positive and negative electrodes.

[0004] Therefore, it is urgent to improve the existing winding cell flattening device to solve the defects of the aforementioned technology. Utility Model Content

[0005] The purpose of this utility model is to provide a pre-kneading fixture for battery cells to address the shortcomings of existing technologies. By pre-kneading the battery cells before flattening, the problem of the tabs turning outward or sinking inward during the flattening process is reduced.

[0006] To achieve the above-mentioned technical objectives, this application implements the following technical means:

[0007] A pre-kneading fixture for a wound battery cell is provided, which is suitable for wound battery cells. The wound battery cell has tabs. The pre-kneading fixture for a wound battery cell is provided with a plurality of first guide grooves and / or a plurality of second guide grooves for inserting the tabs. The second guide grooves are located around all the first guide grooves.

[0008] From top to bottom, the diameter of the first guide groove increases, and / or the diameter of the second guide groove decreases.

[0009] The above-mentioned technical means have produced the following technical effects:

[0010] The pre-kneading fixture for the wound battery cell designed in this utility model, by setting a first guide groove and a second guide groove, effectively guides and pre-kneads the battery cell tabs and ensures that the tabs are fully supported and positioned during the pre-kneading process, preventing sagging or other problems from occurring.

[0011] As a further improvement to the pre-kneading fixture for wound battery cells of this utility model, the pre-kneading fixture for wound battery cells of this application includes a receiving part and a pre-kneading part fixedly connected to the lower surface of the receiving part. The receiving part has an assembly cavity that runs through its upper and lower surfaces. The surface of the pre-kneading part located in the assembly cavity is provided with a first guide groove and / or a second guide groove.

[0012] As a further improvement to the pre-kneading fixture for the wound battery cell of this utility model, the kneading section of the wound battery cell includes a first kneading area and a second kneading area disposed outside the first kneading area; the first kneading area corresponds to the first guide groove, and the second kneading area corresponds to the second guide groove; both the first kneading area and the second kneading area are annular.

[0013] As a further improvement to the pre-kneading fixture for the wound battery cell of this utility model, the angle between the guide of the first guide groove and the perpendicular line of the receiving part is 10-30°; the angle between the guide of the second guide groove and the perpendicular line of the receiving part is 10-30°.

[0014] As a further improvement to the pre-kneading fixture for wound battery cells of this utility model, the diameter of the first guide groove is 2-5mm, and the diameter of the second guide groove is 17-46mm.

[0015] As a further improvement to the pre-kneading fixture for the wound battery cell of this utility model, the width of the first guide groove is 1.0-2.5mm and the width of the second guide groove is 2.5-4.5mm.

[0016] As a further improvement to the pre-kneading fixture for the wound battery cell of this utility model, the depth of the first guide groove is 0.006-0.025mm; the depth of the second guide groove is 0.006-0.025mm.

[0017] As a further improvement to the pre-kneading fixture for the wound battery cell of this utility model, the width of the first guide groove is 0.5-2.0mm and the width of the second guide groove is 2.5-4.5mm.

[0018] As a further improvement to the pre-kneading fixture for the wound battery cell of this utility model, the depth of the first guide groove is 0.004-0.015mm; the depth of the second guide groove is 0.004-0.015mm.

[0019] As a further improvement to the pre-kneading fixture for the wound battery cell of this utility model, the pre-kneading part is circular, and a through hole is provided at its center, which corresponds to the center hole of the wound battery cell. Attached Figure Description

[0020] The accompanying drawings, which are included to provide a further understanding of the present invention and constitute a part of this invention, illustrate exemplary embodiments of the present invention and are used to explain the present invention, but do not constitute an undue limitation of the present invention. In the drawings:

[0021] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of this utility model;

[0022] Figure 2 for Figure 1 Cross-sectional view of AA in the middle;

[0023] Figure 3 for Figure 2 Enlarged view of point B in the middle;

[0024] Figure 4 This is a schematic diagram of the wound battery cell structure in Embodiment 3 of this utility model;

[0025] in:

[0026] 1-Receiving part;

[0027] 11-Assembly cavity;

[0028] 2-Pre-kneading section;

[0029] 21-First guide groove;

[0030] 22-Second guide groove;

[0031] 3-Wound battery cell;

[0032] 31-Ear;

[0033] 32-Place to be kneaded

[0034] 321 - First kneading area;

[0035] 322 - Second kneading area. Detailed Implementation

[0036] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application pertains. The terminology used in the specification of this application is for the purpose of describing specific embodiments only and is not intended to limit this application.

[0037] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; 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; they can refer to the internal communication of two components or the interaction between 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.

[0038] Although this application discloses preferred embodiments as described above, it is not intended to limit the claims. Any person skilled in the art can make several possible changes and modifications without departing from the concept of this application. Therefore, the scope of protection of this application should be determined by the scope defined in the claims of this application.

[0039] The present invention will be further described in detail below with reference to specific embodiments, but the embodiments of the present invention are not limited thereto.

[0040] Implementation Method 1

[0041] like Figure 1-2 As shown, in the current technology, the wound cell 3 neglects the pre-flattening stage when processing the tabs 31, directly flattening the tabs 31. This leads to problems, specifically, during the flattening process of cylindrical lithium-ion batteries, the tabs 31 are prone to outward or inward embedding. This results in uneven surfaces on the tab 31 end, further affecting the welding quality of the current collector. Furthermore, when the outward or inward embedding of the tabs 31 reaches a certain extent, the uneven tabs can puncture the separator, causing a short circuit in the battery.

[0042] To address the shortcomings of current technology, this application specifically designs a pre-kneading fixture for wound battery cells 3. The wound battery cell 3 has tabs 31. The pre-kneading fixture for wound battery cells is provided with multiple first guide grooves 21 and / or multiple second guide grooves 22 for inserting the tabs 31. The second guide grooves 22 are located around all the first guide grooves 21. From top to bottom, the diameter of the first guide grooves 21 increases, and / or the diameter of the second guide grooves 22 decreases.

[0043] The specific working method of this application is as follows: First, the tabs 31 of the wound battery cell 3 are aligned with the first guide groove 21 of the clamp. Since the diameter of the first guide groove 21 gradually increases from top to bottom, this design allows the tabs 31 to be gradually guided and naturally unfolded during insertion, avoiding bending or embedding of the tabs 31 caused by direct insertion. At the same time, the width and depth of the first guide groove 21 are matched with the model of the pre-kneaded battery cell to ensure that the tabs 31 are adequately supported during pre-kneading without being damaged by excessive compression.

[0044] Furthermore, as the tab 31 continues to extend deeper, when it reaches the junction area of ​​the first guide groove 21 and the second guide groove 22, the diameter of the second guide groove 22 is larger than that of the first guide groove 21 (or there may be a design where the diameter gradually decreases, depending on the specific implementation). This change further promotes the smooth transition and flattening of the tab 31. In addition, the width and depth of the second guide groove 22 have also been optimized according to the size and material of the tab 31 to ensure that it can stably support and guide the tab 31 to complete the pre-kneading process. Specifically, the circular design of the pre-kneading part 2 with its central through hole not only facilitates the precise alignment of the clamp and the wound battery cell 3, but also ensures the stability and reliability of the clamp during operation. The correspondence between the through hole and the central hole of the wound battery cell 3 makes the clamp more secure when fixing the battery cell, effectively preventing the problem of uneven pre-kneading or failure of the tab 31 due to clamp shaking.

[0045] In practical applications, users can select a suitable fixture model and adjust the relevant parameters of the first guide groove 21 and the second guide groove 22 according to the specific specifications of the wound battery cell 3 and the size of the tab 31, in order to achieve the best pre-kneading effect. Furthermore, the fixture material must also possess sufficient hardness and wear resistance to withstand long-term working loads and maintain structural stability. In summary, the pre-kneading fixture for the wound battery cell 3 provided in this application achieves effective pre-kneading of the battery cell tab 31, significantly improving the production quality and efficiency of the battery cell, and effectively avoiding unevenness of the tab 31 of the wound battery cell 3 during the flattening stage.

[0046] Implementation Method 2

[0047] like Figure 1 As shown in Figure 4, unlike Embodiment 1, to further improve the clamping and flattening effect of the pre-kneading jig for the wound battery cell in this application, specifically, the pre-kneading jig for the wound battery cell in this application includes a receiving part 1 and a pre-kneading part 2 fixedly connected to the lower surface of the receiving part 1. The receiving part 1 has an assembly cavity 11 extending through its upper and lower surfaces. The surface of the pre-kneading part 2 located within the assembly cavity 11 is provided with a first guide groove 21 and / or a second guide groove 22. This embodiment, by introducing the design of the assembly cavity 11, allows the pre-kneading part 2 to be installed and fixed more flexibly on the receiving part 1, thereby improving the adaptability and durability of the entire jig. Figure 1The connection between the receiving part 1 and the pre-kneading part 2 can be clearly seen. The receiving part 1, as the main structure of the fixture, has an assembly cavity 11 inside that not only provides installation space for the pre-kneading part 2 but also ensures its stability during operation. The design of the assembly cavity 11 allows users to replace the pre-kneading part 2 with different sizes or shapes according to actual needs, adapting to different models of wound battery cells 3, increasing the fixture's versatility and flexibility. The surface of the pre-kneading part 2 located within the assembly cavity 11 also has multiple first guide grooves 21 and / or multiple second guide grooves 22. The design principle of these guide grooves is the same as in embodiment 1, aiming to guide the tab 31 to smoothly transition and naturally flatten through gradually changing diameters or widths.

[0048] Furthermore, the kneading section 32 of the wound cell 3 includes a first kneading area 321 and a second kneading area 322 disposed outside the first kneading area 321. The first kneading area 321 specifically refers to the area inside the wound cell 3 where the wound electrode sheets are located. Its design aims to prevent the electrode tabs 31 near the center hole of the cell from inserting inward due to irregularity of the electrode tabs during the kneading process. The second kneading area 322 is for the electrode tabs 31 of the cell that are far away from the first kneading area 321. It ensures that during the kneading stage, the electrode tabs on the outside of the cell or the electrode tabs 31 adjacent to the first kneading area 321 will not turn outward, thereby avoiding adverse effects on the current collector welding process and ensuring the stability of the cell quality.

[0049] Specifically, the first kneading area 321 corresponds to the first guide groove 21, and the second kneading area 322 corresponds to the second guide groove 22; both the first kneading area 321 and the second kneading area 322 are annular (determined by the shape of the wound battery cell 3).

[0050] Furthermore, in this application, the first guide groove 21 and the second guide groove 22 both point towards the center of the battery cell 3 to be rolled (after the battery cell is assembled in the fixture), that is, the opening directions of the first guide groove 21 and the second guide groove 22 are both towards the central axis of the battery cell. This design ensures that the tab 31 can always move in a stable and consistent direction during insertion and pre-rolling, avoiding the twisting or deformation of the tab 31 caused by inconsistent directions.

[0051] Specifically, the diameter of the first guide groove 21 is 2-5mm. In the specific implementation process, the diameter of the first guide groove 21 can be 2mm, 2.1mm, 2.2mm, 2.3mm, 2.4mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, or 5mm, flexibly selected according to the size and material of the battery cell tab 31. The diameter of the second guide groove 22 is larger than the diameter of the first guide groove 21. The specific value can be adjusted according to the diameter of the first guide groove 21 and the pre-kneading effect to ensure that the tab 31 can unfold smoothly and naturally during the transition. The diameter of the second guide groove 22 is 17-46mm. In the specific implementation process, the diameter of the second guide groove 22 can be 17mm, 18mm, 19mm, 20mm, 22mm, 24mm, 26mm, 28mm, 30mm, 32mm, 34mm, 36mm, 38mm, 40mm, 42mm, 44mm, or 46mm. This design range ensures that the tab 31 can smoothly transition from the first guide groove 21 to the second guide groove 22, while avoiding the problem of insufficient support or poor pre-kneading effect of the tab 31 due to the excessive diameter of the second guide groove 22.

[0052] Specifically, the angle between the guide of the first guide groove 21 and the perpendicular line of the receiving part 1 is 10-30°. In specific implementation, this angle can be 10°, 11°, 12°, 13°, 14°, 15°, 16°, 17°, 18°, 19°, 20°, 21°, 22°, 23°, 24°, 25°, 26°, 27°, 28°, 29° or 30°. The angle between the guide of the second guide groove 22 and the perpendicular line of the receiving part 1 is 10-30°. In specific implementation, this angle can be 10°, 11°, 12°, 13°, 14°, 15°, 16°, 17°, 18°, 19°, 20°, 21°, 22°, 23°, 24°, 25°, 26°, 27°, 28°, 29° or 30°. The above design allows the tab 31 to receive a moderate oblique guiding force when inserted into the first guide groove 21 and the second guide groove 22, which helps the tab 31 to enter more smoothly and unfold along the shape of the guide groove. At the same time, the selection of the above included angle also takes into account the toughness and hardness of the tab 31 material, to ensure that the tab 31 is not damaged during the pre-kneading process, while achieving a good pre-kneading effect.

[0053] In practice, the user can place the wound battery cell 3 on the receiving part 1 of the clamp and adjust the position and angle of the clamp to align the battery cell's tab 31 with the first guide groove 21. Then, gently insert the tab 31 into the first guide groove 21 and observe whether it gradually unfolds and flattens along the expected path as the tab 31 is inserted deeper. After the tab 31 is fully inserted into the first guide groove 21, the user can continue to push the battery cell towards the center of the clamp, allowing the tab 31 to enter the second guide groove 22 for further pre-kneading. Throughout the process, the user can adjust the clamp's tightness according to the actual situation to ensure the best pre-kneading effect.

[0054] Other aspects that are the same as in Implementation Method 1 will not be described again in this implementation method.

[0055] Implementation Method 3

[0056] like Figure 1-4 As shown, unlike Embodiment 1, in order to improve the adaptability of the pre-kneading and flattening fixture for the wound battery cell to the tab 31, specifically, the groove width of the first guide groove 21 of the positive tab (to be kneaded area) of the wound battery cell 3 is 1.0-2.5mm, specifically 1.0mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm, 2.0mm, 2.1mm, 2.2mm, 2.3mm, 2.4mm or 2.5mm. The width of the second guide groove 22 is 2.5-4.5mm, specifically: 2.5mm, 2.6mm, 2.7mm, 2.8mm, 2.9mm, 3.0mm, 3.1mm, 3.2mm, 3.3mm, 3.4mm, 3.5mm, 3.6mm, 3.7mm, 3.8mm, 3.9mm, 4.0mm, 4.1mm, 4.2mm, 4.3mm, 4.4mm or 4.5mm. The depth of both the first guide groove 21 and the second guide groove 22 is 0.006-0.025mm, specifically: 0.006mm, 0.007mm, 0.008mm, 0.009mm, 0.01mm, 0.011mm, 0.012mm, 0.013mm, 0.014mm, 0.015mm, 0.016mm, 0.017mm, 0.018mm, 0.019mm, 0.02mm, 0.021mm, 0.022mm, 0.023mm, 0.024mm, or 0.025mm. This design range ensures that the positive electrode tab can be tightly and stably embedded in the first guide groove 21, while avoiding the problem of the tab 31 shaking or poor pre-kneading effect caused by excessive groove width.

[0057] Specifically, the width of the first guide groove 21 of the negative electrode tab (to be kneaded area) of the wound battery cell 3 is 0.5-2.0mm, specifically: 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1.0mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm or 2.0mm. The width of the second guide groove 22 is 2.5-4.5mm, specifically: 2.5mm, 2.6mm, 2.7mm, 2.8mm, 2.9mm, 3.0mm, 3.1mm, 3.2mm, 3.3mm, 3.4mm, 3.5mm, 3.6mm, 3.7mm, 3.8mm, 3.9mm, 4.0mm, 4.1mm, 4.2mm, 4.3mm, 4.4mm, or 4.5mm. The groove depth of both the first guide groove 21 and the second guide groove 22 is 0.004-0.015mm, specifically: 0.004mm, 0.005mm, 0.006mm, 0.007mm, 0.008mm, 0.009mm, 0.010mm, 0.011mm, 0.012mm, 0.013mm, 0.014mm, or 0.015mm. The above-mentioned size design ensures that the negative electrode tab (the area to be kneaded) of the wound cell 3 can be subjected to pressure evenly and effectively during the pre-kneading process, thereby avoiding the degradation or damage to the cell performance caused by excessive or insufficient pressure.

[0058] Furthermore, to more intuitively demonstrate the technical advantages of the pre-kneading fixture for wound battery cells presented in this application, a comparative experiment was conducted. In the experiment, two groups of battery cell samples were selected: one group underwent pre-treatment using the pre-kneading fixture of this application, while the other group did not undergo any pre-treatment. Subsequently, both groups of battery cells underwent the same flattening process.

[0059] After the leveling process, this application used high-precision flatness testing equipment (such as a laser scanner or microscope) to accurately measure the flatness of the battery cell. A lower flatness value indicates that the number of protrusions and wrinkles in the leveled area of ​​the battery cell is less. Simultaneously, this application also manually inspected the battery cell for any defects such as outward turning or inward insertion during the leveling process and compiled statistics. The specific statistical results are shown in Table 1.

[0060] Serial Number Pre-kneading Outward / inward insertion of the electrode flatness Cell I yes 0 / 10 0.06 Cell II yes 0 / 10 0.05 Cell III yes 0 / 10 0.07 Cell IV no 8 / 10 0.27 Cell IV no 9 / 10 0.29

[0061] Table 1

[0062] According to the above statistics, the pre-kneading process of the wound battery cell 3 in this application achieves the outward / inward folding of the tabs 31, as shown in the statistics of cells I-III. However, looking at the data for cells IV, it is clear that not only are there numerous cases of tabs 31 folding / inward folding, but the interface flatness is also significantly lower than that of cells I-3. Therefore, the pre-kneading fixture for the wound battery cell 3 in this application effectively adjusts the outward / inward folding of the tabs 31, further improving the interface flatness of the kneading area.

[0063] The above are merely preferred embodiments of this application and are not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A pre-kneading fixture for a wound battery cell, suitable for wound battery cells (3), wherein the wound battery cell (3) has tabs (31), characterized in that: The pre-kneading fixture for the wound battery cell is provided with a plurality of first guide grooves (21) and / or a plurality of second guide grooves (22) for inserting the tabs (31), wherein the second guide grooves (22) are located on the periphery of all the first guide grooves (21); From top to bottom, the diameter of the first guide groove (21) increases, and / or the diameter of the second guide groove (22) decreases.

2. The pre-kneading fixture for wound battery cells according to claim 1, characterized in that: It includes a receiving part (1) and a pre-kneading part (2) fixedly connected to the lower surface of the receiving part (1). The receiving part (1) has an assembly cavity (11) that runs through its upper and lower surfaces. The surface of the pre-kneading part (2) located in the assembly cavity (11) is provided with the first guide groove (21) and / or the second guide groove (22).

3. The pre-kneading fixture for wound battery cells according to claim 2, characterized in that: The section (32) to be kneaded of the wound battery cell (3) includes a first kneading area (321) and a second kneading area (322) disposed outside the first kneading area (321). The first kneading area (321) corresponds to the first guide groove (21), and the second kneading area (322) corresponds to the second guide groove (22).

4. The pre-kneading fixture for wound battery cells according to claim 3, characterized in that: Both the first kneading area (321) and the second kneading area (322) are annular.

5. The pre-kneading fixture for wound battery cells according to claim 2, characterized in that: The angle between the guide of the first guide groove (21) and the perpendicular of the receiving part (1) is 10-30°; The angle between the guide of the second guide groove (22) and the perpendicular of the receiving part (1) is 10-30°.

6. The pre-kneading fixture for wound battery cells according to any one of claims 1-5, characterized in that: The width of the first guide groove (21) is 1.0-2.5mm, and the width of the second guide groove (22) is 2.5-4.5mm.

7. The pre-kneading fixture for wound battery cells according to claim 6, characterized in that: The depth of the first guide groove (21) is 0.006-0.025mm; the depth of the second guide groove (22) is 0.006-0.025mm.

8. The pre-kneading fixture for wound battery cells according to any one of claims 1-5, characterized in that: The width of the first guide groove (21) is 0.5-2.0 mm, and the width of the second guide groove (22) is 2.5-4.5 mm.

9. The pre-kneading fixture for wound battery cells according to claim 8, characterized in that: The depth of the first guide groove (21) is 0.004-0.015mm; the depth of the second guide groove (22) is 0.004-0.015mm.

10. The pre-kneading fixture for wound battery cells according to claim 2, characterized in that: The pre-kneading part (2) is circular, and a through hole is provided at its center. The through hole corresponds to the center hole of the wound battery cell (3).

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