A current collector plate structure of a full-tab cylindrical battery cell

Abstract

The utility model discloses a kind of current collecting plate structures of full tab cylindrical battery, including disc body, the disc body is equipped with multiple radial reinforcing ribs, its section is concave convex in steps, and annular welding area is defined on disc body;At least one concentric circular arc-shaped through-hole is provided on the inner side and / or outer side of the annular welding area.The current collecting plate structure of full tab cylindrical battery of the utility model, by the specific layout of reinforcing rib and the relative position design of through-hole, the optimal welding area is structurally clear, effectively avoids the thickness gradually thin weak area of core tab stacking, to solve the problem that diaphragm is easily fused and appears false welding when welding, significantly improve the yield and consistency of welding procedure.

Description

Technical Field

[0001] This utility model relates to the field of battery cell technology, and in particular to a current collector structure for a cylindrical battery cell with multiple tabs. Background Technology

[0002] In cylindrical battery cells with multiple tabs, the welding quality of the current collector and the tabs on the core end face is crucial. Existing current collector structures, such as rigid or flexible connections, typically have a simple planar or fan-shaped welding area, which is not optimized for the uneven thickness distribution of the core tabs in the radial direction. The core end face has a tabless region, a tab stacking gradient region, and a thickness stable region from the inside out. However, the welding area of ​​existing current collectors often covers the uneven thickness gradient region, which makes it easy for local burn-through of the separator or poor solder joints to occur during welding due to inconsistent tab stacking height. The welding quality is difficult to control, which restricts the improvement of battery yield. Utility Model Content

[0003] To address the issues of easily melted diaphragms and incomplete soldering caused by the failure to avoid weak areas in the stacking of core tabs in the welding area of ​​the current collector in existing technologies, this invention proposes a current collector structure for a cylindrical battery cell with all tabs.

[0004] The specific technical solution is as follows:

[0005] A current collector structure for a cylindrical battery cell with all tabs includes a disk body. Multiple radial reinforcing ribs radiating outward from the center of the disk body are formed by stamping and have a stepped cross-section with a concave upper and convex lower section. The radial reinforcing ribs define an annular welding area on the disk body. At least one ring of concentric arc-shaped through holes is formed on the inner and / or outer sides of the annular welding area on the disk body. Through the specific layout and shape of the reinforcing ribs, and by structurally defining a preferred annular welding area, while the design of the through hole positions avoids weak areas in the tab stack, the problem of fused separators and incomplete soldering caused by improper selection of the welding area is fundamentally solved, significantly improving the consistency and reliability of the welding.

[0006] Furthermore, the disc body is circular, and a circular boss, integrally stamped, is provided at the center of the disc body. This circular boss is used to connect with the electrode post. The central boss structure facilitates alignment and pressing with the electrode post, simplifies the assembly process, and improves the stability and current-carrying capacity of the electrode post connection.

[0007] Furthermore, the annular welding area is located between the circular boss and the outer edge of the disc. By precisely defining the welding area within the annular region where the thickness of the tab on the core end face is most stable, the effective welding area is maximized, further ensuring the uniformity of the welding strength.

[0008] Furthermore, the disk includes a circular current-collecting area and an elongated plate-shaped connecting portion extending outward from the edge of the current-collecting area. The end of the connecting portion away from the current-collecting area has a circular through-hole for the passage of the terminal post. This bent current-collecting disk structure provides greater flexibility for the internal layout of the battery, making it particularly suitable for battery designs with specific space requirements.

[0009] Furthermore, the annular welding area is offset on the side of the current collection area away from the connecting part. This asymmetrical welding area layout better adapts to the actual distribution of the core tabs, avoids interference with the connecting part, and ensures the welding area is in the optimal position.

[0010] Furthermore, the number of radial stiffeners is three to six, and the multiple radial stiffeners are evenly distributed along the circumference. A reasonable number of stiffeners ensures structural strength and welding area while avoiding material waste and excessive increases in processing complexity, thus achieving a balance between performance and cost.

[0011] Furthermore, both the upper and lower surfaces of the connecting portion are stamped with inwardly recessed strip-shaped grooves. These grooves serve as pre-defined bending lines, making the bending operation more precise and easier, effectively preventing cracks or positional deviations during the bending process, and improving production yield.

[0012] Furthermore, the width of the concentric arc-shaped through-hole is smaller than the width of the adjacent radial stiffener. This dimensional relationship ensures that the stiffener, which serves as the main structural support and welding platform, has sufficient width and strength, while the through-hole also meets the requirements for electrolyte flow and gas conduction, achieving an optimized allocation of structural and auxiliary functions.

[0013] The above technical solution has the following advantages or technical effects:

[0014] 1. This utility model structurally defines a precise annular welding area on the manifold through a specific layout of radial reinforcing ribs and a stepped cross-section design. This design effectively avoids the thinner area of ​​the stacked tabs on the end face of the core, thus fundamentally solving the technical problems of diaphragm penetration and incomplete weld joints caused by uneven pressure and concentrated heat during welding, significantly improving the reliability and consistency of the welded connection.

[0015] 2. The unique radial reinforcing ribs and the stepped cross-section with concave top and convex bottom adopted in this utility model form an integrated reinforced skeleton, which not only realizes the welding function, but also greatly enhances the overall mechanical strength and deformation resistance of the current collector, ensuring its structural integrity and long-term stability when subjected to external forces during battery assembly and use.

[0016] 3. This utility model simplifies the positioning and operation process of welding and bending assembly through pre-defined and clear physical structural features, reduces excessive reliance on tooling accuracy and operator skills, thereby effectively reducing variations and defects in the production process and improving production cycle time and the yield rate of final products. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the unfolded total electrode plate;

[0018] Figure 2 This is a schematic diagram showing the distribution of the tabs after the end face of the core has been flattened;

[0019] Figure 3 This is a schematic diagram of the non-bending collector structure of this utility model;

[0020] Figure 4 This is a cross-sectional schematic diagram of the assembly of the non-bending current collector, the core, and the pole of this utility model.

[0021] Figure 5 yes Figure 4 Enlarged structural diagram at point A;

[0022] Figure 6 This is a schematic diagram of the bent manifold structure of this utility model;

[0023] Figure 7 This is a schematic diagram of the assembly of the bent collector plate and the pole post after bending.

[0024] The labels in the attached diagram are as follows: 1-Electrode plate, 2-Core, 3-Electrode post, 4-Unbent current collector plate, 4.1-Circular boss, 5-Radial reinforcing rib, 6-Concentric arc-shaped through hole, 7-Annular welding area, 8-Bent current collector plate, 8.1-Connecting part, 8.2-Circular through hole, 8.3-Bending groove, 8.4-Circular mounting hole, 9-Current collection area. Detailed Implementation

[0025] To make the technical solution of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0026] Example 1

[0027] like Figure 1 , Figure 2 As shown, the electrode 1 of the all-tab cell consists of a head tabless region L0, a tab region L1, and a tail tabless region L2. After being wound and flattened, the end face tabs exhibit a characteristic shape. Based on this, this embodiment proposes a current collector structure for an all-tab cylindrical cell, specifically a bend-free current collector 4.

[0028] like Figure 3 , Figure 4 , Figure 5 As shown, the bend-free current collector includes a circular disc body. A circular boss 4.1, integrally stamped, is located at the center of the disc body. This circular boss 4.1 is used for press-fitting with the battery terminal 3 and can be fixed from the terminal 3 end using laser penetration welding. Extending outward from the circular boss 4.1, multiple radial support reinforcement structures, namely radial reinforcing ribs 5, are provided. The radial reinforcing ribs 5 are integrally formed with the disc body, and their cross-section is a stepped shape with a concave upper section and a convex lower section. This structure greatly enhances the overall mechanical strength and deformation resistance of the current collector; the stepped structure naturally defines an annular, raised physical area on the disc body, which is the annular welding area 7 defined in this embodiment.

[0029] The radial reinforcing ribs 5 are precisely positioned on the disc body, and their distance from the center of the collector plate 4 is designed to fall within an annular range of (r3+h, Rh). Here, r0 is the coil radius, r1 is the end radius of a single diaphragm coil, r2 is the starting radius of the negative electrode tabless region, r3 is the starting radius of the positive electrode tabless region, h is the tab height (typically 2-6mm), R is the radius of the core 2, r3+h is the starting radius of the optimal welding area, and Rh is the ending radius of the optimal welding area. This configuration ensures that welding energy is precisely applied to the area with the most stable tab stack thickness on the end face of the core 2, effectively avoiding the gradually weakening tab stack area from r1 to r3. It precisely limits the welding area from a traditional simple planar or fan-shaped region to an optimal annular band obtained through structural calculation and design.

[0030] Between adjacent radial stiffeners 5, multiple concentric arc-shaped through holes 6 are provided. These through holes form an annular flow channel for the flow of electrolyte and the conduction of gas inside the battery. The width of the concentric arc-shaped through holes 6 is designed to be smaller than the width of the adjacent radial stiffeners 5, ensuring that the radial stiffeners 5, which serve as the main structural support and welding platform, have sufficient strength, while the concentric arc-shaped through holes 6 can also meet the needs of auxiliary functions.

[0031] The number of radial stiffeners 5 can be selected as four, and they are evenly distributed along the circumference to provide balanced structural support and welding area. The annular welding area 7 is located between the circular boss 4.1 and the outer edge of the disc.

[0032] This embodiment achieves precise positioning of the welding area and effective avoidance of weak areas through the structural combination of "circular boss 4.1 + radial reinforcing rib 5 at a specific position + concentric arc-shaped through hole 6", which improves the welding yield and significantly reduces the risk of incomplete welding and fusion diaphragm.

[0033] Example 2

[0034] This embodiment proposes a current collector structure for a full-tab cylindrical cell, specifically a bent current collector 8, which is suitable for battery models that require greater design flexibility.

[0035] like Figure 6 , Figure 7 As shown, the bent manifold 8 includes a circular manifold area 9 and a long strip-shaped connecting portion 8.1 extending from the edge of the manifold area 9. A circular through hole 8.2 can be formed in the center of the manifold area 9 for weight reduction and liquid injection. In some applications where the flow requirements are not high, the circular through hole 8.2 can also be omitted. Extending outward from the circular through hole 8.2 (or the center of the manifold area 9), multiple radial support reinforcement structures, namely radial reinforcing ribs 5, are provided. The radial reinforcing ribs 5 have a stepped cross-section with concave upper and convex lower sections, and define an annular welding area 7 on the manifold area 9.

[0036] The position of the annular welding zone 7 is designed according to the characteristics of the bending collector plate 8. Its distance from the center of the collector zone 9 falls within the range of (r1+h, Rh), ensuring the optimal area for welding to act on the end face of the core 2.

[0037] A circular mounting hole 8.4 is provided at the far end of the connecting part 8.1 for the passage of the pole post 3. In order to facilitate the bending operation and ensure the accuracy of the position after bending, inwardly recessed strip grooves, namely bending grooves 8.3, are stamped on both the upper and lower surfaces of the connecting part 8.1. The position of the annular welding area 7 on the current collection area 9 can be selected to be offset to the side away from the connecting part 8.1 to avoid interference with the bent connecting part 8.1.

[0038] An annular flow channel consisting of concentric arc-shaped through holes 6 is provided between adjacent radial reinforcing ribs 5.

[0039] Example 2, through the combination of "current collection area 9 (including core welding structure) + connecting part 8.1 with bending groove 8.3", provides flexibility in spatial layout while achieving the core advantages of Example 1, ensuring high welding quality and meeting the design requirements of specific battery structures.

[0040] This invention adapts the optimal welding annular area position parameters to different overall current collector structures (non-bent current collector 4 / bent current collector 8), i.e., the welding area is defined by the structure. The current collector is preferably made of aluminum or aluminum alloy using a one-piece stamping process to ensure structural integrity and conductivity. The number of radial reinforcing ribs 5 is not limited to four; it can be selected from three to six to accommodate the needs of cells with different diameters.

[0041] The embodiments described above are merely illustrative of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of this utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. A current collector structure for a fully tabbed cylindrical battery cell, comprising a disk body, characterized in that, The disc body is provided with a plurality of radial reinforcing ribs radiating outward from its central region. The radial reinforcing ribs are formed by stamping and have a stepped cross-section that is concave at the top and convex at the bottom. The radial reinforcing ribs define an annular welding area on the disc body. At least one ring of concentric arc-shaped through holes is provided on the disc body on the inner and / or outer side of the annular welding area.

2. The current collector structure of a fully tabbed cylindrical battery cell according to claim 1, characterized in that, The disc body is circular, and a circular boss integrally stamped in the center of the disc body is provided, which is used to connect with the pole post.

3. The current collector structure of a fully tabbed cylindrical battery cell according to claim 2, characterized in that, The annular welding area is located between the circular boss and the outer edge of the disk.

4. The current collector structure of a fully tabbed cylindrical battery cell according to claim 1, characterized in that, The disk body includes a circular current collection area and a long strip-shaped connecting part extending outward from the edge of the current collection area. The end of the connecting part away from the current collection area has a circular through hole for passing through the pole post.

5. The current collector structure of a fully tabbed cylindrical battery cell according to claim 4, characterized in that, The annular welding zone is offset on the side of the current collection zone away from the connection portion.

6. The current collector structure of a fully tabbed cylindrical battery cell according to claim 1, characterized in that, The number of radial stiffeners is three to six, and the plurality of radial stiffeners are evenly distributed along the circumference.

7. The current collector structure of a fully tabbed cylindrical battery cell according to claim 4, characterized in that, The upper and lower surfaces of the connecting part are both stamped with inwardly recessed strip-shaped grooves.

8. The current collector structure of a fully tabbed cylindrical battery cell according to claim 1, characterized in that, The width of the concentric arc-shaped through hole is smaller than the width of the adjacent radial reinforcing rib.

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