Battery cell current collector and pole connecting structure and battery
By designing the connection structure of the battery cell current collector and pole column in the battery product, and using the adapter column and busbar to achieve plane-plane welding, the problems of heat generation and large current output limitation during use of the battery product are solved, and the problem of the battery product is achieved. Improved flow capability and improved battery performance.
Patent Information
- Application Number
- CN202420761248.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-15
- Publication Date
- 2025-02-21
- Estimated Expiration
- 2034-04-15
AI Technical Summary
During use, the heat generated by the connection between parts affects the product's performance and service life, and there are problems such as high current output limitation and reduced volume energy density.
By designing a connecting structure for battery cell current collector and pole column, plane-to-plane welding is achieved using adapter columns and busbars, increasing the welding area to enhance overcurrent capacity and reducing heat generation.
The overcurrent capability is improved, heat generation is reduced, the power characteristics and safety of the battery are improved, and the volume and material cost of the battery are reduced.
Smart Images
Figure CN222515005U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of batteries, in particular to a connection structure of a battery core current collector and a pole, and a battery. Background Art
[0002] With the development of the new energy industry, the size and capacity of battery products are bound to increase. The heat generated by this type of product during use is one of the important factors affecting product performance. Considering the flow capacity of battery structural components and reducing the heat generated during electronic transmission through sufficient flow area is an effective response strategy.
[0003] At present, the connection structure between the current collector and the pole of the mainstream full-ear cylindrical batteries and capacitors on the market is as follows: Figure 8 As shown in the figure: the current collector and busbar I are laser welded, and busbar I and pole I are rigidly laser welded, and the overall size is fixed. This connection structure is limited to cylindrical battery products. It is difficult to achieve when used in square battery products. In addition, the amount of copper raw materials used is large, which increases the product cost. There is also a connection structure such as Fig. 9 As shown in the figure: Busbar II is an integrated structure. It is bent multiple times, and one end is laser welded to the current collector and the other end is laser welded to the pole II, thereby achieving the purpose of conducting current. However, this connection structure has the following defects: (1) Busbar II has multiple bending operations. Considering that the force required for bending becomes large, the winding core is squeezed and it is easy to break when bending, the thickness of busbar II is difficult to make thick; (2) Due to the multiple bending fillets, the space occupied by busbar II as a whole is large, resulting in a decrease in the volume energy density of the battery cell product; (3) Due to the limited current capacity, the smaller cross-sectional area in the round battery cell will increase the heat generation of the product and affect the performance of the battery cell.
[0004] This application is proposed in order to fundamentally solve the limitation of battery products on large current output and reduce the problem of heat generation caused by the connection between components during product use, which affects product performance and service life. Utility Model Content
[0005] In view of the above-mentioned shortcomings of the prior art, the utility model provides a battery core current collector and pole connection structure and a battery.
[0006] In order to achieve the above-mentioned purpose, the main technical solutions adopted by the utility model include:
[0007] On the one hand, the utility model proposes a connection structure between a battery cell current collector and a pole, which is used to realize the connection between the pole and the current collector exposed at both ends of the winding core, including: a transfer column and a bus, the pole is a hollow pole, a connecting surface is arranged in the hollow pole, the bus includes a bus body, one end of the transfer column is connected to the connecting surface, and the other end is connected to the bus body, and the bus body is connected to the current collector.
[0008] Preferably, a through hole I is provided in the middle of the busbar body.
[0009] Preferably, a surface of the busbar body facing the pole is provided with a plurality of strip-shaped grooves distributed along the periphery of the through hole I.
[0010] Preferably, the thickness T1 of the adapter post satisfies: 0.5 mm ≤ T1 ≤ 20 mm, preferably 3 mm ≤ T1 ≤ 10 mm, 5 mm ≤ T1 ≤ 8 mm.
[0011] Preferably, the cross-section of the adapter column is at least one of circular, square, and diamond-shaped. When the adapter column is a cylinder, the diameter D of its cross-section satisfies: 5mm≤D≤50mm, preferably 10mm≤D≤30mm, and more preferably 15mm≤D≤25mm. The connecting surface is located in the cylinder and the outer periphery of the connecting surface is connected to the inner wall of the cylinder so that the connecting surface is horizontally arranged.
[0012] Preferably, the thickness T2 of the busbar satisfies: 0.2 mm ≤ T2 ≤ 2 mm, preferably 0.5 mm ≤ T2 ≤ 1.0 mm, and more preferably 0.5 mm ≤ T2 ≤ 0.8 mm.
[0013] Preferably, a positioning groove I is provided on a surface of the bus body facing the pole and corresponding to the pole, a positioning groove II is provided on another surface of the bus body, and a through hole II is also provided on the bus body.
[0014] On the other hand, the utility model proposes a battery, including: a cover plate, a winding core and a shell, the cover plate is provided with a pole, both ends of the winding core have current collectors exposed, and the exposed current collectors are connected to the poles through the above-mentioned battery cell current collector and pole connection structure.
[0015] Preferably, the shape of the winding core includes: any one of cylindrical, square, annular, and polygonal; when the winding core is cylindrical, its height H2 and diameter D satisfy the following relationship: 60mm≤H2≤500mm, 30mm≤D≤250mm.
[0016] Preferably, the height H1 of the current collector exposed from the winding core satisfies: 1 mm ≤ H1 ≤ 20 mm, preferably 5 mm ≤ H1 ≤ 10 mm.
[0017] The utility model realizes plane-to-plane welding through the adapter column and the busbar, and the increase of the welding area ensures the overcurrent capacity of the entire charging and discharging process, helps to enhance the overcurrent capacity and reduce the heat generated by the overcurrent.
[0018] Compared with the prior art, the utility model has at least the following beneficial effects:
[0019] 1. Strong overcurrent capacity and less heat generated by overcurrent, which effectively reduces the heat generated by the battery in the structural connection, improves the power characteristics of the battery, and ensures the safety of the battery;
[0020] 2. The compact structure occupies less space, which helps to reduce the space volume of inactive materials in the battery, improve the volume energy density, and reduce material costs. In the same volume, more active materials can be used, and the performance is more advantageous. Under the same performance requirements, the volume of the product can be made smaller;
[0021] 3. It is suitable for battery cell structures of various shapes, which not only removes the volume restriction of battery cells, but also reduces the difficulty of battery cell design, which in turn helps to reduce production costs. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.
[0023] Figure 1 This is an exploded diagram of the structure of the battery proposed in the utility model;
[0024] Figure 2 This is a schematic diagram of the structure of the battery proposed by the utility model;
[0025] Figure 3 for Figure 1 and Figure 2 Schematic diagram of the structure of the middle cover;
[0026] Figure 4 for Figure 1 and Figure 2 Schematic diagram of the cross-sectional structure of the middle pole;
[0027] Figure 5 for Figure 1 and Figure 2 Schematic diagram of the structure of the middle bus;
[0028] Figure 6 for Figure 1 Schematic diagram of the connection structure between the transfer column and the busbar;
[0029] Figure 7 A cross-sectional view of the battery provided by the utility model;
[0030] Figure 8 For the existing connection structure one;
[0031] Fig. 9 For the existing connection structure 2.
[0032] In the figure: A1, bus I; A2, bus II; B1, pole I; B2, pole II; 1, cover; 11, cover body; 12, pole; 121, connection surface; 13, insulating layer; 14, injection hole; 15, pressure relief valve; 2, adapter column; 3, bus; 31, bus body; 32, through hole I; 33, strip groove; 34, positioning groove I; 35, positioning groove II; 36, through hole II; 4, winding core; 5, shell. DETAILED DESCRIPTION
[0033] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.
[0034] The inventor of the present application has found in practice that the existing technology for enhancing the flow capacity of battery components to reduce heat generation during battery use has the defects of limited improvement in flow capacity and sacrificing battery volume energy density and battery cell performance. In view of the above defects, the present utility model is proposed.
[0035] like Figure 1 and Figure 2 As shown in the figure: The utility model provides a battery, including: a cover plate 1, a winding core 4, and a shell 5, as shown in Figure 3 As shown: the cover plate 1 specifically includes a cover plate body 11, on which a pole 12, an insulating layer 13, a liquid injection hole 14 and a pressure relief valve 15 are provided (all of which are prior arts and will not be repeated); the shape of the winding core 4 includes: any one of cylindrical, square, annular, and polygonal (the shape of the cover plate 1 matches it), when the winding core 4 is cylindrical, its height H2 and diameter D satisfy the following relationship: 60mm≤H2≤500mm, 30mm≤D≤250mm, the winding core 4 is located in the shell 5 (usually an aluminum shell) and both ends of the winding core 4 have current collectors exposed, and the height H1 of the current collector exposed by the winding core 4 satisfies: 1mm≤H1≤20mm, and the exposed current collector is connected to the pole 12 through the battery cell current collector and pole connection structure.
[0036] It should be noted that:
[0037] (1) The exposed current collector of the winding core 4 should not be too high or too low. If it is too low, it will be unfavorable for welding with the busbar, affecting the operability and welding effect of welding. If it is too high, it will cause material waste and increase costs. The applicant has verified through practice that the height of the exposed current collector is preferably between 1mm-20mm, and 5mm-10mm is the best. In this height range, the winding core 4 with full tabs can obtain a larger welding area to ensure the current capacity of the entire charging and discharging process.
[0038] (2) The above connection is specifically laser welding, and the pole 12, the current collector exposed by the winding core 4, and the connection structure between the current collector and the pole are preferably made of the same material, including but not limited to copper, aluminum, etc.
[0039] (3) Through creative work, the applicant has learned that when the height H2 and diameter D of the winding core 4 satisfy the following relationship: 60mm≤H2≤500mm, 30mm≤D≤250mm, the battery can obtain the maximum capacity in a limited space, and the structure is stable and not easily deformed or damaged. It can also effectively reduce heat accumulation and improve battery safety.
[0040] Further, if Figure 4 , Figure 5 , Figure 6 , Figure 7 As shown in common: the battery cell current collector and pole connection structure includes: a transfer column 2 and a bus 3, the pole 12 is a hollow pole, a connecting surface 121 is provided in the hollow pole (the connecting surface 121 is preferably an integrated structure with the pole 12), the bus 3 includes a bus body 31, one end of the transfer column 2 is connected to the connecting surface 121, and the other end is connected to the bus body 31, and the bus body 31 is connected to the collector.
[0041] During the specific operation: the winding core 4 is formed by stacking the positive electrode, the negative electrode and the diaphragm, and then the exposed foil at both ends is shaped to make the foil layer compact and tight, and then it is laser welded with the bus 3 by the same material, and the welding track on the bus 3 is adjusted so that the flow area meets the design requirements; the top end of the adapter column 2 is inserted into the pole 12 and laser welded with the connecting surface 121 by the same material, and the welding track is adjusted so that the connecting surface 121 and the adapter column 2 are melted and the flow area meets the design requirements; the bottom end of the adapter column 2 is in planar contact with the bus 3, and the same material of the two parts is melted together by laser welding to achieve the set flow area.
[0042] The current collectors exposed at both ends of the winding core 4 are connected to the outside of the winding core 4 through the busbar 3 and the adapter post 2. The design structure of the busbar 3 and the adapter post 2 not only occupies a small space, but also does not involve multiple bending of the busbar, which helps to design the busbar to have a certain thickness under the premise of considering the current capacity, and the busbar 3 and the adapter post 2 are welded between planes, which helps to significantly increase the welding area and ensure the current capacity of the entire charging and discharging process, thereby reducing the heat generated by the conductor transmitting electrons during the use of the product. In addition, the design structure of the adapter post and the busbar to achieve plane-to-plane welding has no requirements on the shape of the battery cell and no restrictions on the volume of the battery cell, which helps to reduce the difficulty of battery cell design and thus reduce production costs.
[0043] The above embodiment is applicable to a winding core without a core rod. When used for a winding core with a core rod, a through hole Ⅰ32 is opened in the middle of the bus body 31 to facilitate the passage of the core rod. The inner circumferential shape of the through hole Ⅰ32 is adapted to the outer circumferential shape of the core rod. The bus 3 is passed through the through hole Ⅰ32 on the core rod and is laser welded with the exposed current collectors at both ends of the winding core 4 by using the same material.
[0044] As a preferred technical solution, in another embodiment of the utility model, a plurality of strip grooves 33 distributed along the periphery of the through hole Ⅰ 32 are provided on a surface of the busbar body 31 facing the pole 12. Through the plurality of strip grooves 33, the electrolyte can be easily infiltrated and the injection and infiltration time can be shortened. Of course, the strip grooves 33 can also be designed as openings of other shapes, such as circular, elliptical, fan-shaped, square or irregular shapes, etc. This embodiment is only an example and is not limited.
[0045] As a preferred technical solution, in another embodiment of the utility model, the thickness T1 of the adapter column 2 satisfies: 0.5mm≤T1≤20mm, preferably 3mm≤T1≤10mm, 5mm≤T1≤8mm. The thickness T1 here specifically refers to the height of the adapter column 2, not the wall thickness of the adapter column 2. The thickness T1 should not be too large or too small. Although T1 is too large and has strong current flow capacity, it occupies a large space, which not only affects the volume energy density of the battery, but also increases the material cost; T1 is too small, which will cause the current flow capacity to fail to meet the design requirements. Comprehensive consideration: it is appropriate for the thickness T1 of the adapter column 2 to meet the above range.
[0046] On the basis of the previous embodiment, the cross-section of the adapter post 2 is at least one of circular, square, and diamond-shaped; when the adapter post 2 is a cylinder, a cross-sectional area that is too small will increase the heat generation of the adapter post 2, thereby affecting the performance of the battery cell. Practice has confirmed that the diameter D of the cross-section of the cylindrical adapter post needs to satisfy: 5mm≤D≤50mm, preferably 10mm≤D≤30mm, and more preferably 15mm≤D≤25mm. The connecting surface 121 is located in the cylinder and the outer periphery of the connecting surface 121 is connected to the inner wall of the cylinder so that the connecting surface 121 is horizontally arranged.
[0047] When the adapter column 2 is welded to the pole 12, the upper end surface of the adapter column 2 extends into the pole 12 and contacts the connecting surface 121. When the connecting surface 121 is horizontally arranged, its contact surface is a horizontal plane. By adjusting the facing area and welding area of the upper end surface and the connecting surface 121, a sufficiently large current capacity can be obtained.
[0048] As a preferred technical solution, in another embodiment of the present utility model, the thickness T2 of the busbar 3 satisfies: 0.2mm≤T2≤2mm, preferably 0.5mm≤T2≤1.0mm, and more preferably 0.5mm≤T2≤0.8mm.
[0049] A thicker busbar has a larger cross-sectional area and can accommodate more current, so it has a higher current capacity, and has good heat dissipation performance, high mechanical strength and stability, which can ensure the safe and stable use of the battery. However, an overly thick busbar will increase the weight of the battery and increase the cost. After comprehensive consideration, in order to achieve good current capacity and take into account the weight and cost of the battery, the thickness T2 of the busbar 3 should be between 0.2mm-2mm, preferably 0.5mm-1.0mm, and 0.5mm-0.8mm is the best.
[0050] As a preferred technical solution, in another embodiment of the utility model, a positioning groove Ⅰ34 is provided on a surface of the bus body 31 facing the pole 12 corresponding to the pole 12, and a positioning groove Ⅱ35 is provided on the other surface of the bus body 31. A through hole Ⅱ36 corresponding to the position of the injection hole 14 is also opened on the bus body 31 to facilitate the flow of electrolyte into the winding core.
[0051] In order to improve the accuracy and reliability of welding, ensure the stability and accuracy of the connection position between the busbar 3, the transfer column 2 and the current collector, and do not increase the cost and floor space of the production line, the two surfaces of the busbar body 31 are respectively provided with positioning grooves I 34 and II 35. The positioning groove I 34 is used for welding positioning of the transfer column 2, and the positioning groove II 35 is convenient for identification when the busbar 3 and the current collector exposed outside the winding core are laser welded, so as to locate the welding track; the positioning grooves I 34 and II 35 are both located on the busbar 3 and avoid the strip groove 33, and neither penetrates, leaving a thickness of about 0.5 mm for connection during laser welding, which helps to improve welding efficiency and welding quality.
[0052] Although the embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and cannot be understood as limiting the present invention. A person skilled in the art may change, modify, replace and deform the above embodiments within the scope of the present invention. In addition, a person skilled in the art may combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.
Claims
1. A battery core current collector and pole connection structure, used to achieve the connection between the pole (12) and the current collector exposed at both ends of the winding core, characterized in that: include: The adapter column (2) and the busbar (3) are provided with a hollow pole column, a connection surface (121) is arranged inside the hollow pole column, and the busbar (3) comprises a busbar body (31), one end of the adapter column (2) is connected to the connection surface (121), and the other end is connected to the busbar body (31), and the busbar body (31) is connected to the current collector.
2. The battery core current collector and pole connection structure according to claim 1, characterized in that: A through hole I (32) is provided in the middle of the busbar body (31).
3. The battery core current collector and pole connection structure according to claim 2, characterized in that: A plurality of strip-shaped grooves (33) distributed along the periphery of the through hole I (32) are arranged on a surface of the busbar body (31) facing the pole (12).
4. The battery core current collector and pole connection structure according to claim 1 or 2, characterized in that: The thickness T1 of the adapter column (2) satisfies: 0.5 mm ≤ T1 ≤ 20 mm.
5. The battery core current collector and pole connection structure according to claim 4, characterized in that: The cross section of the adapter column (2) is at least one of a circular shape, a square shape, and a diamond shape; when the adapter column (2) is a cylinder, the diameter D of its cross section satisfies: 5 mm ≤ D ≤ 50 mm, the connection surface (121) is located inside the cylinder, and the outer periphery of the connection surface (121) is connected to the inner wall of the cylinder so that the connection surface (121) is arranged horizontally.
6. The battery core current collector and pole connection structure according to claim 1 or 2, characterized in that: The thickness T2 of the busbar (3) satisfies: 0.2 mm ≤ T2 ≤ 2 mm.
7. The battery core current collector and pole connection structure according to claim 1 or 2, characterized in that: A positioning groove I (34) is provided on a surface of the busbar body (31) facing the pole (12) and corresponding to the pole (12), a positioning groove II (35) is provided on another surface of the busbar body (31), and a through hole II (36) is also provided on the busbar body (31).
8. A battery comprising: A cover plate (1), a winding core (4) and a shell (5), wherein a pole (12) is arranged on the cover plate (1), and current collectors are exposed at both ends of the winding core (4), characterized in that the exposed current collector is connected to the pole (12) through a battery cell current collector and pole connection structure as described in any one of claims 1 to 7.
9. The battery according to claim 8, characterized in that The shape of the winding core (4) includes: any one of cylindrical, square, annular, and polygonal; when the winding core (4) is cylindrical, its height H2 and diameter D satisfy the following relationship: 60mm≤H2≤500mm, 30mm≤D≤250mm.
10. The battery according to claim 8, characterized in that The height H1 of the current collector exposed from the winding core (4) satisfies: 1 mm ≤ H1 ≤ 20 mm.