A battery busbar and cylindrical battery using the same
By designing edge notches and internal notches on the lithium battery bus disk, the safety hazards of lithium batteries during large-scale discharge and the problem of uniform dispersion of electrolytes is solved, and more efficient electrolyte flow and battery overcurrent capabilities are achieved.
Patent Information
- Application Number
- CN202420813566.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-18
- Publication Date
- 2025-04-11
- Estimated Expiration
- 2034-04-18
AI Technical Summary
When the current lithium battery current collector disk is discharged at a large rate, the electron transmission path is long and the polarization is large, the battery generates serious heat, which poses safety risks, and there are shortcomings in the uniform dispersion of the electrolyte.
A battery bus disk is designed, including a bus disk body, an edge notch and an internal notch that penetrates the bus disk body. The edge notch and an internal notch are used as the circulation channels of the electrolyte, which promotes the infiltration of the electrolyte against the electrode group and improves the liquid injection efficiency of the electrolyte.
Through the design of multiple edge notches and internal notches, the flow efficiency and uniform dispersion of the electrolyte are significantly improved, the battery heat generation is reduced, and the battery's overcurrent capability and use safety is enhanced.
Smart Images
Figure CN222749657U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of batteries, in particular to a battery busbar and a cylindrical battery using the same. Background Art
[0002] With the rapid development of power tools, the requirements for battery output power have been further improved, and the requirements for rate-type batteries are even higher. Under high-rate discharge, traditional single-electrode or dual-electrode batteries have long electron transmission paths, large polarization, and severe battery heating, which can easily cause safety hazards in battery use.
[0003] CN214043712U discloses a lithium battery collector disk, which includes a disk body, and at least one circle of circular grooves is provided on one side of the disk body, and the circular grooves are arranged in concentric circles with the center of the disk body as the center of the circle. The other side of the disk body is provided with a convex structure arranged in concentric circles at a position corresponding to the circular grooves, and the convex structure is welded to the pole ear. The welding of the pole ear and the convex structure increases the welding points of the whole pole ear, so that the welding tension between the lithium battery collector disk and the whole pole ear is large, thereby solving the problem that the welding points of the collector disk are easy to loosen when the lithium battery collector disk is welded and closed, resulting in insufficient pole ear flow area. At the same time, the lithium battery collector disk also has an electrolyte channel between adjacent convex structures, so that the electrolyte can be dispersed more evenly during the addition of electrolyte and the operation of the battery. However, when the area of the current collecting plate is large, the electrolyte cannot be reliably evenly dispersed only through the electrolyte channel. Therefore, in actual use, this method is not conducive to the infiltration of the electrolyte into the electrode group, and the injection efficiency when adding the electrolyte is not high. Utility Model Content
[0004] In order to overcome the problem of certain randomness of test results in the prior art, the utility model provides a battery busbar and a cylindrical battery using the same. The battery busbar and the cylindrical battery using the same are provided with edge notches and internal notches, which can make the flow of electrolyte more efficient, facilitate the infiltration of electrolyte into the electrode group, and also improve the injection efficiency of electrolyte.
[0005] In order to achieve the above-mentioned purpose, the utility model provides a battery busbar, wherein the battery busbar comprises a busbar body (1), an edge notch (2) and an internal notch (3) penetrating the busbar body (1), wherein a plurality of the edge notches (2) are provided, and the plurality of the edge notches (2) are located at the edge of the busbar body (1) and are evenly distributed around the center of the busbar body (1), and the internal notch (3) is provided in the middle of the busbar body (1).
[0006] Preferably, the width of the edge notch (2) is set to 0.1-1.2 mm.
[0007] Preferably, the number of the edge notches (2) is set to 2-10.
[0008] Preferably, a plurality of the internal notches (3) are provided, and the plurality of the internal notches (3) are evenly distributed around the center of the busbar body (1).
[0009] Preferably, the inner notch (3) has a width of 0.1-1.2 mm.
[0010] The utility model also provides a cylindrical battery using the battery busbar, the cylindrical battery comprising a wound electrode group (4) and the battery busbar, the battery busbar comprising a positive electrode busbar and a negative electrode busbar, the wound electrode group (4) comprising a positive electrode full-pole ear end and a negative electrode full-pole ear end located at two ends;
[0011] The positive busbar and the negative busbar are electrically connected to the positive full-pole tab end and the negative full-pole tab end, respectively.
[0012] Preferably, a metal protrusion (5) is provided on a side of the negative electrode busbar that faces away from the negative electrode full-pole ear end.
[0013] Preferably, a plurality of the metal protrusions (5) are provided, and the plurality of the metal protrusions (5) are located at the center of the negative electrode busbar.
[0014] Preferably, the metal bump (5) has a width of 0.1-4.0 mm and a height of 0.05-1.0 mm.
[0015] According to the above technical solution, a plurality of edge notches and internal notches are provided on the busbar body, and these edge notches and internal notches provided through the busbar can serve as circulation channels for the electrolyte, which is conducive to the infiltration of the electrolyte into the wound electrode group in the battery. Moreover, when injecting the electrolyte into the battery, these edge notches and internal notches can also facilitate the circulation of the electrolyte in the battery, thereby improving the efficiency of the injection.
[0016] A wound electrode group is arranged in the battery housing, and a positive electrode tab and a negative electrode tab are arranged at both ends of the wound electrode group, and two battery busbars are connected to the positive electrode tab and the negative electrode tab respectively by laser welding. This method increases the welding area between the wound electrode group and the battery busbar, which is beneficial to increase the welding area and tension between the battery busbar and the tabs at both ends of the wound electrode group, improves the battery overcurrent energy, and reduces the internal resistance of the battery, which is beneficial to reduce the heat generation of the battery.
[0017] After the winding electrode group is welded to the battery busbars at both ends, the two battery busbars are respectively welded to the two ends of the battery shell to complete the battery production.
[0018] Other features and advantages of the present invention will be described in detail in the subsequent specific implementation section. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] Figure 1 It is a front view of a battery busbar;
[0020] Figure 2 yes Figure 1 Sectional drawing;
[0021] Figure 3 It is a schematic diagram of the structure of a cylindrical battery.
[0022] Description of Reference Numerals
[0023] 1 Busbar body 2 Edge notch
[0024] 3 internal notches 4 winding pole group
[0025] 5Metal bumps 6Area between adjacent notches
[0026] 10Battery housing DETAILED DESCRIPTION
[0027] In the present invention, unless otherwise stated, directional words such as "edge, center, middle, back, both ends" generally refer to the orientation of the term in normal use, or are common names understood by those skilled in the art, and should not be regarded as limitations on the term.
[0028] See also Figure 1-2 The battery busbar comprises a busbar body 1, an edge slot 2 and an internal slot 3 penetrating the busbar body 1, wherein a plurality of edge slots 2 are provided, the plurality of edge slots 2 are located at the edge of the busbar body 1, the plurality of edge slots 2 are evenly distributed around the center of the busbar body 1, and the internal slot 3 is provided in the middle position of the busbar body 1.
[0029] Through the implementation of the above technical solution, a plurality of edge notches 2 and internal notches 3 are provided on the busbar body 1. These edge notches 2 and internal notches 3 provided through the busbar can serve as circulation channels for the electrolyte, which is beneficial for the electrolyte to infiltrate the wound electrode group 4 in the battery. Moreover, when the electrolyte is injected into the battery, these edge notches 2 and internal notches 3 can also facilitate the circulation of the electrolyte in the battery, thereby improving the efficiency of the injection.
[0030] The battery housing 10 is provided with a wound electrode group 4, and the two ends of the wound electrode group 4 are respectively provided with a positive electrode ear and a negative electrode ear, and two battery busbars are respectively connected to the positive electrode ear and the negative electrode ear by laser welding. This method increases the welding area between the wound electrode group 4 and the battery busbar, which is beneficial to increase the welding area and tension between the battery busbar and the two end ears of the wound electrode group 4, improves the battery overcurrent energy, and reduces the internal resistance of the battery, thereby helping to reduce the heat generation of the battery.
[0031] After the wound electrode group 4 is welded to the battery busbars at both ends, the two battery busbars are respectively welded to the two ends of the battery housing 10 to complete the battery production.
[0032] In this embodiment, preferably, the width of the edge notch 2 is set to 0.1-1.2 mm.
[0033] The edge notch 2 is not only conducive to the flow of electrolyte, but also conducive to releasing the welding stress between the tab and the battery busbar to avoid cold welding. However, after the edge notch 2 is set, the tab can only be welded with the adjacent notch area 6. Therefore, after the edge notch 2 is set, the actual welding area of the tab is reduced. In order to ensure the current capacity of the battery as much as possible, the width of the edge notch 2 needs to be reasonably set to reduce the impact on the tab welding.
[0034] When the width of the edge notch 2 is less than 0.1 mm, the resistance of the electrolyte passing through the edge notch 2 is large due to the small gap, which is not conducive to the flow of the electrolyte during the use of the battery. Therefore, the width of the edge notch 2 needs to be greater than 0.1 mm.
[0035] However, the width of the edge notch 2 cannot be greater than 1.2 mm. Because when the width of the edge notch 2 is greater than 1.2 mm, when the full pole ear and the busbar body 1 are laser welded, some joints of the full pole ear cannot be reliably welded to the busbar body 1, which reduces the current capacity of the battery and also increases the internal resistance of the battery, affecting the performance of the battery.
[0036] Therefore, the width of the edge notch 2 is set to 0.1-1.2 mm. Preferably, by providing a plurality of edge notches 2, better flowability of the electrolyte inside the battery can be achieved.
[0037] In this embodiment, preferably, the number of the edge notches 2 is set to 2-10.
[0038] The plurality of edge notches 2 are evenly distributed around the center of the busbar body 1, which is more conducive to the uniform dispersion of the electrolyte inside the cylindrical battery.
[0039] Preferably, the cross-section of the edge notch 2 can be set to a rectangular or arc shape, etc., as long as the cross-section shape is conducive to the circulation of the electrolyte and does not affect the welding of the electrode tab.
[0040] In this embodiment, preferably, a plurality of internal notches 3 are provided, and the plurality of internal notches 3 are evenly distributed around the center of the busbar body 1 .
[0041] Preferably, the cross section of the internal notch 3 can be set to a rectangular or arc shape, and the cross-sectional shape is conducive to the circulation of the electrolyte and does not affect the welding of the electrode tab.
[0042] In this embodiment, preferably, the width of the inner notch 3 is 0.1-1.2 mm.
[0043] The internal notch 3 is not only conducive to the flow of electrolyte, but also conducive to releasing the welding stress between the tab and the battery busbar, thereby avoiding the occurrence of cold welding.
[0044] When the width of the inner notch 3 is less than 0.1 mm, the resistance of the electrolyte passing through the inner notch 3 is large due to the small gap, which is not conducive to the effective flow of the electrolyte during the use of the battery. Therefore, the width of the inner notch 3 needs to be greater than 0.1 mm.
[0045] However, the width of the internal notch 3 cannot be greater than 1.2 mm. Because when the width of the internal notch 3 is greater than 1.2 mm, when the full pole ear and the busbar body 1 are laser welded, some joints of the full pole ear cannot be reliably welded to the busbar body 1, which reduces the current capacity of the battery and also increases the internal resistance of the battery, affecting the performance of the battery.
[0046] Therefore, the width of the inner notch 3 is set to 0.1-1.2 mm.
[0047] See also Figure 3 A cylindrical battery using a battery busbar, the cylindrical battery comprises a wound electrode group 4 and a battery busbar, the battery busbar comprises a positive electrode busbar and a negative electrode busbar, the wound electrode group 4 comprises a positive electrode full-pole ear end and a negative electrode full-pole ear end located at both ends;
[0048] The positive busbar and the negative busbar are electrically connected to the positive full-pole tab end and the negative full-pole tab end respectively.
[0049] The positive electrode full-pole lug end and the negative electrode full-pole lug end can be electrically connected to the positive electrode busbar and the negative electrode busbar respectively by welding. In order to ensure the reliability of welding between the lug and the busbar body 1, laser welding can be used to achieve the connection between the lug and the busbar body 1. At the same time, in order to save manufacturing costs, resistance welding can be used to achieve the connection between the battery shell 10 and the busbar body 1.
[0050] In this embodiment, preferably, a metal bump 5 is provided on a side of the negative electrode busbar that faces away from the negative electrode full-pole lug end.
[0051] When the negative busbar and the negative electrode full-ear end are connected by resistance welding, the welding needle extends from the positive end of the wound electrode group 4 through the center hole to the negative end, and can cooperate with another welding needle outside the battery case 10 to clamp the battery case 10 and the negative busbar. After starting the resistance welding equipment, the welding needle is pressed, and current is formed between the welding needles, thereby generating high temperature, melting the metal protrusion 5, so that the negative busbar and the battery case 10 are connected.
[0052] In this embodiment, preferably, a plurality of metal protrusions 5 are provided, and the plurality of metal protrusions 5 are located at the center of the negative electrode busbar.
[0053] The metal bumps 5 are welding materials for resistance welding, and the welding needs to be achieved with the help of the current of the welding needle. Therefore, in order to better utilize the electric field and achieve a better welding effect, the metal bumps 5 need to be evenly distributed around the central hole of the wound electrode group 4.
[0054] The center hole of the wound electrode group 4 is consistent with the center position of the busbar body 1, so the metal protrusion 5 can be set at the center position of the negative electrode busbar during production. Preferably, the metal protrusion 5 can be evenly distributed in a circle with the center of the busbar body 1 as the center.
[0055] In this embodiment, preferably, the metal bump 5 has a width of 0.1-4.0 mm and a height of 0.05-1.0 mm.
[0056] The height of the metal bump 5 is limited to 0.05-1.0 mm, on the one hand to avoid the increase in manufacturing cost due to excessive height, and on the other hand to avoid the height of the metal bump 5 occupying the battery space and affecting the battery capacity design.
[0057] The metal protrusion 5 can be set to be a spherical shape, the diameter of the spherical shape at the contact point with the busbar body 1 is 0.1-4.0 mm, or other circular or annular protrusion structures with the same cross-sectional area.
[0058] Preferably, the metal protrusion 5 is set as a circular ring structure to help reduce the manufacturing cost of the busbar, and can also be applicable to a variety of welding methods to meet the design requirements of batteries of different models.
[0059] Pole ears are provided at both ends of the wound electrode group 4. The material of the pole ears may be metal materials such as copper, aluminum, nickel, and copper-plated nickel. The diameter of the busbar body 1 is 0.4-0.8mm smaller than the diameter of the battery shell 10. Accordingly, there is a gap of 0.2-0.4mm between the disc body 1 and the shell 6, so that the battery busbar can be smoothly installed in the shell 6.
[0060] The preferred embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, and these simple modifications all belong to the protection scope of the present invention.
[0061] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present utility model will not further describe various possible combinations.
[0062] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.
Claims
1. A battery busbar, characterized in that: The battery busbar comprises a busbar body (1), an edge notch (2) penetrating the busbar body (1), and an internal notch (3), wherein a plurality of the edge notches (2) are provided, the plurality of edge notches (2) are located at the edge of the busbar body (1) and are evenly distributed around the center of the busbar body (1), and the internal notch (3) is provided at a middle position of the busbar body (1).
2. The battery busbar according to claim 1, characterized in that: The width of the edge notch (2) is set to 0.1-1.2 mm.
3. The battery busbar according to claim 2, characterized in that: The number of the edge notches (2) is set to be 2-10.
4. The battery busbar according to claim 1, characterized in that: A plurality of the internal notches (3) are provided, and the plurality of the internal notches (3) are evenly distributed around the center of the busbar body (1).
5. The battery busbar according to claim 4, characterized in that: The width of the inner notch (3) is 0.1-1.2 mm.
6. A cylindrical battery using the battery busbar according to any one of claims 1 to 5, characterized in that: The cylindrical battery comprises a wound electrode group (4) and the battery busbar, the battery busbar comprises a positive electrode busbar and a negative electrode busbar, and the wound electrode group (4) comprises a positive electrode full-pole ear end and a negative electrode full-pole ear end located at two ends; The positive busbar and the negative busbar are electrically connected to the positive full-pole tab end and the negative full-pole tab end, respectively.
7. The cylindrical battery according to claim 6, characterized in that: A metal protrusion (5) is provided on a side of the negative electrode busbar facing away from the negative electrode full-pole ear end.
8. The cylindrical battery according to claim 7, characterized in that: A plurality of the metal protrusions (5) are provided, and the plurality of the metal protrusions (5) are located at the center of the negative electrode busbar.
9. The cylindrical battery according to claim 7, characterized in that: The metal bump (5) has a width of 0.1-4.0 mm and a height of 0.05-1.0 mm.