Large-current current collector and pole connecting structure and battery
By designing the connection structure between the high current collector and the pole, the problem of insufficient overcurrent capacity and excessive heat generation of the battery when outputting large current is solved, achieving higher overcurrent capacity and lower heat generation, and improving the battery performance. performance and security.
Patent Information
- Application Number
- CN202420761211.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-15
- Publication Date
- 2025-01-21
- Estimated Expiration
- 2034-04-15
AI Technical Summary
Existing battery products have problems such as insufficient overcurrent capability and excessive heat generation when outputting large currents, which affects product performance and service life.
A high-current current collector and pole connection structure is adopted. By designing the structures of the second busbar and the first busbar, the welding area of the current collector and the busbar and the overflow cross-sectional area of the busbar itself are increased, thereby enhancing the overcurrent. capacity and reduce heat production.
The overcurrent capability of the battery is improved, the heat generated by overcurrent is reduced, the power characteristics and safety factor of the battery are improved, and the volume and material cost of the battery are reduced.
Smart Images
Figure CN222380803U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of batteries, in particular to a large current collector and pole connection structure 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, reducing the heat generated during electron transmission through sufficient flow area is an effective response strategy. The capacity of lithium battery products has increased in recent years, which means that the input and output currents are getting larger and larger at the same rate. In addition, supercapacitor products have high power output as a key feature, and the use of large currents has also increased. In batteries with full-ear structures, the connection between the current collector and the pole becomes one of the key links to limit current output.
[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 7 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 Figure 8 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 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 large 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 large-current collector and pole connection structure for realizing the connection between the pole and the collector in the battery, including: a second bus and a first bus; the second bus includes: a bus body II, a bus body I and a connecting edge formed in one piece, there is an angle between the bus body II and the bus body I, and the connecting edge is located on the end of the bus body I opposite to the bus body II; the first bus includes the bus body III; the second bus is connected to the pole through the connecting edge, the first bus is connected to the collector, and the second bus is connected to the first bus through the bus body II.
[0008] Preferably, a through hole II is provided at the connection between the bus body II and the bus body I, and a through hole I is provided in the middle of the bus body III.
[0009] Preferably, the thickness T of the second busbar satisfies: 0.2 mm ≤ T ≤ 5 mm, preferably 0.5 mm ≤ T ≤ 2.5 mm, and more preferably 0.5 mm ≤ T ≤ 1 mm.
[0010] Preferably, the outer dimensions and thickness of the first busbar are consistent with the outer dimensions and thickness of the second busbar.
[0011] Preferably, the connecting edge and the bus body I are transitioned by an arc, and the angle β between the connecting edge and the bus body I satisfies: 30°<β<150°, preferably 45°≤β≤90°; the angle α between the bus body II and the bus body I satisfies: 90°<α<180°, preferably 120°≤α≤150°.
[0012] Preferably, the through hole II is a strip-shaped through hole, and the strip-shaped through hole passes through the bus body II and the bus body I, and most of the strip-shaped through hole is located on the bus body I.
[0013] Preferably, a strip-shaped groove is provided on the busbar body III along the outer periphery of the through hole I.
[0014] On the other hand, the utility model proposes a battery, including: a cover plate, a winding core and a shell, wherein a pole is arranged on the cover plate, current collectors are exposed at both ends of the winding core, and the exposed current collectors are connected to the poles through the above-mentioned large 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, more preferably 5 mm ≤ H1 ≤ 15 mm.
[0017] The utility model increases the welding area between the collector and the bus bar and the flow cross-sectional area of the bus bar itself through the structural design and connection of the first bus bar and the second bus bar, which helps to enhance the flow capacity and reduce the heat generated by the flow.
[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 and helps to improve the power characteristics and safety factor of the battery;
[0020] 2. The compact structure takes up less space, which helps to reduce the space volume of inactive materials in the battery, increase the volume energy density and reduce material costs;
[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 The structure of the battery proposed by the utility model is shown in FIG. Figure 1 ;
[0024] Figure 2 The structure of the battery proposed by the utility model is shown in FIG. Figure 2 ;
[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 A schematic diagram of the structure of the second bus;
[0027] Figure 5 for Figure 1 and Figure 2 A schematic diagram of the structure of the first bus;
[0028] Figure 6 for Figure 1 and Figure 2 Schematic diagram of the connection structure of the middle cover plate, the second bus bar and the first bus bar;
[0029] Figure 7 For the existing connection structure one;
[0030] Figure 8 For the existing connection structure 2.
[0031] In the figure: A1, bus I; A2, bus II; B1, pole I; B2, pole II; 1, cover; 11, cover body; 12, pole; 13, insulating layer; 14, injection hole; 15, pressure relief valve; 2, second bus; 21, bus body I; 22, bus body II; 23, connecting edge; 24, through hole II; 3, first bus; 31, bus body III; 32, through hole I; 33, strip groove; 4, winding core; 5, shell. DETAILED DESCRIPTION
[0032] 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.
[0033] 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.
[0034] 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, both ends of the winding core 4 have exposed current collectors, 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 a large current collector and pole connection structure.
[0035] It should be noted that:
[0036] (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-15mm 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.
[0037] (2) The above connection is preferably laser welding, and the pole 12, the current collector exposed by the winding core 4, and the high-current current collector and the pole connection structure are preferably made of the same material, including but not limited to copper, aluminum, etc.
[0038] (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.
[0039] Further, if Figure 4 , Figure 5 , Figure 6 As shown in common: the high-current collector and pole connection structure includes: a second bus 2 and a first bus 3, the second bus 2 includes: a bus body II 22, a bus body I 21 and a connecting edge 23, the bus body II 22 and the bus body I 21 form an angle, and the connecting edge 23 is located on the end of the bus body I 21 opposite to the bus body II 22; the first bus 3 includes a bus body III 31; the second bus 2 is connected to the pole 12 through the connecting edge 23, the first bus 3 is connected to the collector exposed on the winding core 4, and the second bus 2 is connected to the first bus 3 through the bus body II 22; through holes are correspondingly provided at the positions of the second bus 2 and the first bus 3 facing the injection hole 14 to facilitate injection operations (not shown in the figure).
[0040] During the specific operation: the winding core 4 is formed by stacking the positive electrode, the negative electrode and the separator, 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 first bus 3 by the same material, and the welding track on the first bus 3 is adjusted so that the flow area meets the design requirements; the pole 12 and the second bus 2 are laser welded with the same material, and the welding track on the second bus 2 is adjusted so that the second bus 2 and the pole 12 are melted and the flow area meets the design requirements; the bus body II22 of the second bus 2 is brought into planar contact with the first bus 3, and the same material of the two is melted together by laser welding to achieve the set flow area.
[0041] The current collectors exposed at both ends of the winding core 4 are finally connected to the outside of the winding core 4 through the connection of the first bus 3 and the second bus 2. The design structure of the two busbars 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. Moreover, the first busbar 3 and the second busbar 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 outer dimensions and thickness of the second busbar 2 and the first busbar 3 can be the same or different. The design structure of the two busbars 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.
[0042] As a preferred technical solution, in another embodiment of the present utility model, the thickness T of the second busbar 2 satisfies: 0.2mm≤T≤5mm, preferably 0.5mm≤T≤2.5mm, and more preferably 0.5mm≤T≤1mm.
[0043] 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. Taking all factors into consideration, in order to achieve good current capacity and take into account the weight and cost of the battery, the thickness T of the second busbar 2 should preferably meet 0.2mm≤T≤5mm, preferably 0.5mm≤T≤2.5mm, and more preferably 0.5mm≤T≤1mm.
[0044] As a preferred technical solution, in another embodiment of the utility model, the outer dimensions and thickness of the first bus bar 3 are consistent with the outer dimensions and thickness of the second bus bar 2, and the outer dimensions of the first bus bar 3 are consistent with the outer dimensions of the second bus bar 2, which helps to maintain the stability of the battery structure; the thickness of the first bus bar 3 and the second bus bar 2 are both between 0.2mm-5mm and are the same, which helps to obtain better current carrying capacity.
[0045] As a preferred technical solution, in another embodiment of the utility model, the connecting edge 23 and the bus body I21 are transitioned by an arc, and the angle β between the connecting edge 23 and the bus body I21 satisfies: 30°<β<150°, preferably 45°≤β≤90°; the angle α between the bus body II22 and the bus body I21 satisfies: 90°<α<180°, preferably 120°≤α≤150°.
[0046] When the cover plate 1 completely blocks the housing 5, the cover plate 1 is parallel to the first bus 3. At this time, the angle between the cover plate 1 and the bus body Ⅰ21 and the angle between the bus body Ⅰ21 and the bus body Ⅱ22 are the same and both are obtuse angles. Although the second bus 2 has good elasticity and toughness, considering that it has a certain thickness in order to ensure a certain flow capacity, too much bending will not only easily occupy a large space, but also cause tearing. Therefore, the angle β between the connecting edge 23 and the bus body Ⅰ21 and the angle α between the bus body Ⅱ22 and the bus body Ⅰ21 are preferably obtuse angles, so that the deformation of the second bus 2 during the packaging process of the cover plate 1 can be minimized, so that it has a relatively thick thickness.
[0047] The above implementation is applicable to winding cores without core rods. When used for winding cores with core rods, a through hole II24 for the core rod to pass through is provided at the connection between the bus body II22 and the bus body I21, and a through hole I32 is provided in the middle of the bus body III31. In order not to affect the flipping of the cover plate 1, the through hole II24 is a strip-shaped through hole, which passes through the bus body II22 and the bus body I21. Most of the strip-shaped through holes are located on the bus body I21. When the cover plate 1 is flipped, the core rod can be flexibly inserted into and out of the strip-shaped through hole. The first bus 3 is inserted on the core rod through the through hole I32 and is laser-welded with the current collectors exposed at both ends of the winding core 4 by the same material.
[0048] As a preferred implementation method, in another embodiment of the utility model, on the bus body III31, specifically, the surface of the bus body III31 facing the cover plate 1 is provided with a strip groove 33 along the outer periphery of the through hole I32. When the bus body III31 is circular, the strip groove 33 is preferably arranged along the radial direction of the circle. Through a plurality of strip grooves 33, the electrolyte can be easily infiltrated and the injection and infiltration time can be shortened. Of course, the strip groove 33 can also be designed as an opening of other shapes, such as circular, elliptical, arc-shaped, etc. The utility model is only an example and is not limited.
[0049] 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 high current collector and pole connection structure, used to achieve the connection between the pole and the current collector in a battery, characterized in that: include: A second busbar (2) and a first busbar (3); The second busbar (2) comprises: a busbar body II (22), a busbar body I (21) and a connecting edge (23) which are integrally formed, wherein the busbar body II (22) and the busbar body I (21) form an angle, and the connecting edge (23) is located at an end of the busbar body I (21) opposite to the busbar body II (22); The first busbar (3) comprises a busbar body III (31); The second busbar (2) is connected to the pole via a connecting edge (23), the first busbar (3) is connected to the current collector, and the second busbar (2) is connected to the first busbar (3) via a busbar body II (22).
2. The high current collector and pole connection structure according to claim 1, characterized in that: A through hole II (24) is provided at the connection between the bus body II (22) and the bus body I (21), and a through hole I (32) is provided in the middle of the bus body III (31).
3. The high current collector and pole connection structure according to claim 1 or 2, characterized in that: The thickness T of the second busbar (2) satisfies: 0.2 mm ≤ T ≤ 5 mm.
4. The high current collector and pole connection structure according to claim 3, characterized in that: The outer dimensions and thickness of the first busbar (3) are consistent with the outer dimensions and thickness of the second busbar (2).
5. The high current collector and pole connection structure according to claim 1 or 2, characterized in that: The connecting edge (23) and the bus body I (21) are transitioned by an arc, and the angle β between the connecting edge (23) and the bus body I (21) satisfies: 30°<β<150°; the angle α between the bus body II (22) and the bus body I (21) satisfies: 90°<α<180°.
6. The high current collector and pole connection structure according to claim 2, characterized in that: The through hole II (24) is a strip-shaped through hole, which passes through the bus body II (22) and the bus body I (21), and most of the strip-shaped through hole is located on the bus body I (21).
7. The high current collector and pole connection structure according to claim 2, characterized in that: A strip-shaped groove (33) is provided on the busbar body III (31) along the outer periphery of the through hole I (32).
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 large 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.