Collector piece and power battery

Abstract

The invention discloses a current collector and a power battery, the current collector comprises a shell welding area, the shell welding area is connected with a wing part, an interval groove is formed in the current collector, and the interval groove enables the wing part to form an extension arm extending out of the shell welding area, an extension part located on one side of the extension arm and a connecting area; the interval groove terminates the end, close to the shell welding area, of the connection area and enables the end, close to the shell welding area, of the extension part to form a free end separated from the extension arm and the shell welding area, the connection area comprises a first area away from the interval groove and a second area located between the first area and the interval groove, and the second area is provided with a plurality of through holes; the through holes are sequentially arranged from the position adjacent to the interval groove to the position connected with the first area, bridging parts are formed between the through holes adjacent to the interval groove and the interval groove and between the adjacent through holes respectively, and the bridging parts are configured to be broken when pulled. According to the invention, the bridging part can assist overcurrent before being pulled apart, and the elasticity of the connection area can be improved after the bridging part is pulled apart.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a current collector and a power battery. Background Art

[0002] Application number CN202311361386.4 discloses a current collecting sheet. The current collecting sheet includes a shell welding area, at least one end of the shell welding area is connected to a wing, and a spacing groove is formed on the current collecting sheet. The spacing groove enables the wing to form a connecting arm extending from the shell welding area and an extension portion spaced apart from the connecting arm. The end of the connecting arm away from the shell welding area is connected to the end of the extension portion away from the shell welding area. The extension portion has a free end spaced apart from the shell welding area. The extension portion is used for welding with the full pole ear of the winding core, and the connection area between the connecting arm and the extension portion can be elastically deformed. When the cylindrical battery equipped with the current collecting sheet causes the winding core to jump due to vibration after loading and drives the extension portion to jump together, the connection area between the connecting arm and the extension portion can be elastically deformed to release the impact stress, thereby avoiding the risk of open circuit at the welding position of the shell welding area and the bottom wall of the shell, and improving the seismic performance of the cylindrical battery. However, the patent solution has the following technical problems:

[0003] In order to ensure the elastic deformation capacity of the connection area, the length of the connection area cannot be too long. Although this is beneficial to the seismic performance of the cylindrical battery, it also sacrifices the current flow capacity of the connection area to a certain extent, which is not conducive to suppressing the temperature rise of the battery. Moreover, when the current collector is in a loose state, it is relatively easy to deform when subjected to force. Summary of the invention

[0004] The purpose of this application is to provide a current collector and a power battery that can solve at least one technical problem mentioned in the background technology.

[0005] In order to achieve the above-mentioned purpose, the present application provides a current collecting sheet, including a shell welding area, the shell welding area is connected to a wing portion, and a spacing groove is formed on the current collecting sheet, the spacing groove enables the wing portion to form an extension arm extending from the shell welding area, an extension portion located on one side of the extension arm, and a connection area connected between the extension arm and the extension portion, the spacing groove terminates one end of the connection area close to the shell welding area and enables one end of the extension portion close to the shell welding area to form a free end spaced apart from the extension arm and the shell welding area, the extension portion is used for welding with the full pole ear of the winding core, the connection area includes a first area away from the spacing groove and a second area located between the first area and the spacing groove, the second area is provided with a plurality of through holes, the plurality of through holes are arranged in sequence from a position adjacent to the spacing groove to a position connected to the first area, and bridge portions are respectively formed between the through holes adjacent to the spacing groove and the spacing groove and between adjacent through holes, and each of the bridge portions is configured to be disconnected when pulled.

[0006] Optionally, the spacing groove includes a first branch groove and a second branch groove connected to each other, the first branch groove separates the side edge of the free end of the extension part from the extension arm, and the second branch groove separates the end edge of the free end of the extension part from the shell welding area; the connection area terminates at the first branch groove, and when each of the bridging parts is disconnected, the first branch groove is extended.

[0007] Optionally, the spacing groove is substantially L-shaped, and the second branch groove penetrates the current collecting plate outwardly.

[0008] Optionally, the wing portion includes two extension arms, the extension portion is connected between the two extension arms via two connection areas located on both sides thereof, and both ends of the second branch groove are respectively connected to the first branch groove.

[0009] Optionally, the spacing groove is substantially U-shaped.

[0010] Optionally, the through holes are arranged linearly.

[0011] Optionally, the spacing groove includes a linear branch groove directly opposite to each of the through holes.

[0012] Optionally, the current collecting piece includes two wing portions, which are respectively connected to opposite ends of the shell welding area.

[0013] Optionally, the current collecting sheet is formed by slotting a strip sheet.

[0014] In order to achieve the above-mentioned purpose, the present application also provides a power battery, including the current collecting sheet as described above.

[0015] In the embodiment of the present application, the second area of ​​the connection area between the extension arm and the extension part is provided with a plurality of through holes arranged in sequence from the position adjacent to the spacing groove to the position connected to the first area, and bridges are formed between the through holes adjacent to the spacing groove and the spacing groove, and between adjacent through holes. When the current collector is not installed, that is, in a loose state, although the second area of ​​the connection area has a plurality of through holes, the extension part and the extension arm are still connected by the bridges located in the second area, and the connection of the bridges can assist in preventing the deformation of the current collector. When the current collector is assembled in the power battery for normal charging and discharging, if the bridge has not been torn off before, the extension arm and the extension part can pass current through the bridge in addition to the first area, which is beneficial to improve the temperature rise of the power battery. When the power battery vibrates after being installed on the vehicle, causing the core to jump and driving the extended part to jump together, the bridging part will be pulled. When the pulling force exceeds a certain level, at least part of the bridging part will be disconnected, dynamically improving the elasticity of the connection area. The elastic deformation of the connection area is then more conducive to releasing the impact stress caused by the jumping of the extension part, reducing the risk of open circuit in the welding area between the shell welding area and the shell. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the structure of the current collecting sheet of the embodiment of the present application.

[0017] Figure 2 It is a schematic diagram of the top view of the structure after the current collecting sheet and the winding core are assembled in the embodiment of the present application.

[0018] Figure 3 It is a schematic diagram of the exploded structure of the power battery of an embodiment of the present application.

[0019] Figure 4 It is a schematic diagram of the cross-sectional structure of the power battery of an embodiment of the present application.

[0020] Figure 5 It is a schematic structural diagram of a current collecting sheet according to another embodiment of the present application. DETAILED DESCRIPTION

[0021] In order to explain the technical content, structural features, and achieved effects of the present application in detail, the following is a detailed description in conjunction with the implementation methods and the accompanying drawings.

[0022] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0023] See also Figures 1 to 4 The embodiment of the present application discloses a current collecting sheet 1, including a shell welding area 11, the shell welding area 11 is connected to a wing 12, and a spacing groove 13 is formed on the current collecting sheet 1, the spacing groove 13 makes the wing 12 form an extension arm 121 extending from the shell welding area 11, an extension part 122 located on one side of the extension arm 121, and a connection area 123 connected between the extension arm 121 and the extension part 122, the spacing groove 13 terminates one end of the connection area 123 close to the shell welding area 11 and makes one end of the extension part 122 close to the shell welding area 11 form a self-spaced from the extension arm 121 and the shell welding area 11. From the end 124, the extension portion 122 is used for welding with the full pole ear of the winding core 2, and the connection area 123 includes a first area 125 away from the spacing groove 13 and a second area 126 located between the first area 125 and the spacing groove 13. The second area 126 is provided with a plurality of through holes 127, and the plurality of through holes 127 are arranged in sequence from a position adjacent to the spacing groove 13 to a position connected to the first area 125. Bridge portions 128 are respectively formed between the through holes 127 adjacent to the spacing groove 13 and the spacing groove 13 and between adjacent through holes 127, and each bridge portion 128 is configured to be disconnected when pulled.

[0024] In the embodiment of the present application, the second area 126 of the connection area 123 between the extension arm 121 and the extension part 122 is provided with a plurality of through holes 127 arranged in sequence from the position adjacent to the spacing groove 13 to the position connected to the first area 125, and bridges 128 are respectively formed between the through holes 127 adjacent to the spacing groove 13 and the spacing groove 13 and between the adjacent through holes 127. When the current collecting sheet 1 is not installed, that is, in a loose state, although the second area 126 of the connection area 123 has a plurality of through holes 127, the extension part 122 and the extension arm 121 are still connected by the bridges 128 located in the second area 126, and the connection function of the bridges 128 can help prevent the deformation of the current collecting sheet 1. When the current collector 1 is assembled in the power battery for normal charging and discharging, if the bridge portion 128 has not been torn off before, the extension arm 121 and the extension portion 122 can flow through the bridge portion 128 in addition to the first area 125, which is beneficial to improve the temperature rise of the power battery. When the power battery is installed on the vehicle and the vibration causes the winding core 2 to jump and drives the extension portion 122 to jump together, the bridge portion 128 will be pulled. When the pulling force exceeds a certain degree, at least part of the bridge portion 128 will be disconnected, dynamically improving the elasticity of the connection area 123, and then the elastic deformation of the connection area 123 is more conducive to releasing the impact stress caused by the jumping of the extension portion 122, reducing the risk of open circuit at the welding position between the shell welding area 11 and the shell 3.

[0025] It should be noted that the present application does not limit the shape, size, and size of the through holes 127, and whether the through holes 127 are the same, as long as the through holes 127 are arranged in sequence along the second region 126 and a bridge 128 can be formed between adjacent through holes 127 and between the through holes 127 and the spacing groove 13, and the bridge 128 can be pulled apart when the vibration of the power battery exceeds a certain degree. The through holes 127 and the bridge 128 can be set based on several vibration experiments to meet the needs.

[0026] It should be noted that, depending on the degree of vibration, the bridges 128 may not necessarily be disconnected at substantially the same time, and some bridges 128 may be disconnected while others are not, which can still enhance the elasticity of the connection area 123. Generally, the disconnection of at least some of the bridges 128 will extend the spacing groove 13 along the path, which is more conducive to the elastic deformation of the connection area 123.

[0027] It should be noted that the present application does not limit the specific shape of the current collecting plate 1, as long as it can be divided into an extension arm 121, an extension portion 122 and a connection area 123 based on the setting of the spacing groove 13, and the connection area 123 is formed with multiple through holes 127 and multiple bridging portions 128 that can be pulled apart in the aforementioned manner.

[0028] At least one welding track 129 is formed on the extension portion 122, and the welding track 129 is configured to conduct all the tabs of each layer from the inner circle to the outer circle of the winding core 2. The welding track 129 can be in a straight line or spiral appearance, etc., which is not limited.

[0029] In some embodiments, the spacing groove 13 includes a first branch groove 131 and a second branch groove 132 connected to each other, the first branch groove 131 separates the side edge of the free end 124 of the extension portion 122 from the extension arm 121, and the second branch groove 132 separates the end edge of the free end 124 of the extension portion 122 from the shell welding area 11; the connection area 123 terminates at the first branch groove 131, and when each bridging portion 128 is disconnected, the first branch groove 131 is extended.

[0030] Specifically, the spacing groove 13 is substantially L-shaped, and the second branch groove 132 penetrates the current collecting plate 1 outward.

[0031] In some embodiments, the through holes 127 are arranged linearly, that is, arranged along a straight line, but it is not limited thereto, for example, they may also be arranged along a curve.

[0032] Specifically, the spacing groove 13 includes linear branch grooves 131 directly facing each through hole 127. However, the present invention is not limited thereto.

[0033] Specifically, the shell welding area 11 is configured to be assembled corresponding to the central hole 21 of the winding core 2. After the current collecting sheet 1 and the winding core 2 are assembled, the shell welding area 11 at least partially extends outward beyond the central hole 21 of the winding core 2 to facilitate welding. Optionally, the shell welding area 11 extends outward beyond the central hole 21 of the winding core 2 as a whole, that is, the projection of the central hole 21 of the winding core 2 on the current collecting sheet 1 is located on the inner side of the outer periphery of the shell welding area 11.

[0034] exist Figure 1 In the example shown, the shell welding area 11 is roughly rectangular, and the width of the shell welding area 11 between the two spacing grooves 13 is greater than the diameter of the center hole 21 of the winding core 2. After the collecting sheet 1 and the winding core 2 are assembled, the two ends of the shell welding area 11 extend outward beyond the center hole 21 of the winding core 2.

[0035] exist Figure 1 In the example shown, the shell welding area 11 is generally rectangular in shape, but is not limited thereto. For example, the shell welding area 11 may also be generally circular, etc.

[0036] In some embodiments, the current collector 1 includes two wings 12 connected to opposite ends of the shell welding area 11 , and the extensions 122 of the two wings 12 can be welded to the full tabs on both sides of the central hole 21 of the winding core 2 .

[0037] Specifically, the wing portions 12 at opposite ends of the shell welding area 11 are arranged in an axisymmetric manner, but this is certainly not limited to this.

[0038] It should be noted that when the current collecting sheet 1 includes two wings 12, it is not limited to being connected to the opposite ends of the shell welding area 11, for example, in some embodiments, the two wings 12 can be connected to the adjacent two ends of the current collecting sheet 1. In addition, the number of wings 12 is not limited to two, for example, it can also be one, three, or four.

[0039] For example, when the shell welding area 11 is rectangular, only one side, any two sides, three sides, or all four sides may be connected to the wing 12 .

[0040] In short, as long as at least one end of the current collecting piece 1 is connected with the wing portion 12 as described above, it is within the protection scope of the present application.

[0041] Specifically, the current collecting sheet 1 is formed by slotting a strip sheet. Since the current collecting sheet 1 is formed by slotting a strip sheet, the material used can be significantly reduced compared to the commonly used complex structure current collecting sheet 1, which is more conducive to reducing production costs. More specifically, the current collecting sheet 1 can be a relatively regular strip structure with a relatively consistent width, and its width is smaller than the radius of the winding core 2.

[0042] It should be noted that the current collecting sheet 1 is formed by slotting a strip sheet, which does not mean that no other processing is performed on the strip sheet.

[0043] Of course, the current collecting sheet 1 is not limited to being formed by slotting a strip-shaped sheet.

[0044] Specifically, the material of the current collecting sheet 1 is copper, nickel, copper-nickel composite strip or aluminum. Of course, the current collecting sheet 1 can also be made of other materials.

[0045] Figure 5 The current collecting sheet 1 in another example is shown. Figure 1 The main difference between the current collector 1 shown in the example is that the wing 12 of the current collector 1 in this example includes two extension arms 121 extending from the shell welding area 11 to the same side, the extension 122 is connected between the two extension arms 121 through two connection areas 123 located on both sides thereof, and the two ends of the second branch groove 132 are respectively connected to the first branch groove 131. When the current collector 1 requires a relatively large area, the current collector 1 form in this example can be considered.

[0046] Further, in this example, the spacing groove 13 is substantially U-shaped.

[0047] See also Figures 1 to 4 The present application also discloses a power battery, comprising the current collector 1 as described above.

[0048] In the embodiment of the present application, when the power battery is normally charged and discharged, the extension arm 121 and the extension part 122 can flow through the bridge parts 128 in addition to the first area 125, which is beneficial to improve the temperature rise of the power battery. When the power battery is installed on the vehicle and vibrates, causing the winding core 2 to jump and driving the extension part 122 to jump together, the bridge part 128 will be pulled. When the pulling force exceeds a certain degree, at least part of the bridge part 128 will be disconnected, dynamically improving the elasticity of the connection area 123, and then the elastic deformation of the connection area 123 is more conducive to releasing the impact stress caused by the jumping of the extension part 122, reducing the risk of open circuit at the welding position between the shell welding area 11 and the shell 3.

[0049] Specifically, the power battery is a cylindrical power battery.

[0050] Specifically, the power battery includes a winding core 2 and a shell 3, the shell welding area 11 is arranged corresponding to the central hole 21 of the winding core 2 and welded to the bottom wall 31 of the shell 3, and the extension portion 122 is welded to the full pole ear of the winding core 2. Of course, the shell welding area 11 is not limited to being welded to the bottom wall 31 of the shell 3, and may also be welded to the cover body (not shown) of the shell 3.

[0051] Specifically, the full-tab welding of the extension portion 122 and the winding core 2 is performed by laser welding.

[0052] Specifically, the shell welding area 11 is welded to the bottom wall 31 of the shell 3 by resistance welding. Of course, it is not limited to this, for example, laser welding or penetration welding can also be used.

[0053] In a specific example, the power battery can be assembled through the following assembly process:

[0054] Weld the extended portion 122 of the current collector 1 to the full tab of the winding core 2 so that the shell welding area 11 of the current collector 1 corresponds to the central hole 21 of the winding core 2;

[0055] Place the winding core 2 into the housing 3 so that the current collecting sheet 1 faces the bottom wall 31 of the housing 3;

[0056] The shell welding area 11 of the current collecting sheet 1 is welded to the bottom wall 31 of the shell 3 by using the central hole 21 of the winding core 2 .

[0057] The above disclosure is only a preferred example of the present application, and its role is to facilitate the technical personnel in this field to understand and implement it. Of course, it cannot be used to limit the scope of rights of the present application. Therefore, equivalent changes made according to the scope of the patent application of the present application still fall within the scope covered by the present application.

Claims

1. A current collecting sheet, characterized in that: The invention comprises a shell welding area, the shell welding area is connected with a wing part, and a spacing groove is formed on the current collecting sheet, the spacing groove enables the wing part to form an extension arm extending from the shell welding area, an extension part located on one side of the extension arm, and a connection area connected between the extension arm and the extension part, the spacing groove terminates one end of the connection area close to the shell welding area and enables one end of the extension part close to the shell welding area to form a free end spaced apart from the extension arm and the shell welding area, the extension part is used for welding with the full pole ear of the winding core, the connection area comprises a first area away from the spacing groove and a second area located between the first area and the spacing groove, the second area is provided with a plurality of through holes, the plurality of through holes are arranged in sequence from a position adjacent to the spacing groove to a position connected to the first area, and bridge parts are respectively formed between the through holes adjacent to the spacing groove and the spacing groove and between adjacent through holes, and each of the bridge parts is configured to be disconnected when pulled.

2. The current collecting sheet according to claim 1, characterized in that: The spacing groove includes a first branch groove and a second branch groove that are connected, the first branch groove separates the side edge of the free end of the extension part from the extension arm, and the second branch groove separates the end edge of the free end of the extension part from the shell welding area; the connection area terminates at the first branch groove, and when each of the bridging parts is disconnected, the first branch groove is extended.

3. The current collecting sheet according to claim 2, characterized in that: The spacing groove is substantially L-shaped, and the second branch groove penetrates the current collecting plate outwardly.

4. The current collecting sheet according to claim 2, characterized in that: The wing portion includes two extension arms, the extension portion is connected between the two extension arms via two connection areas located on both sides thereof, and both ends of the second branch groove are respectively connected to the first branch groove.

5. The current collecting sheet according to claim 4, characterized in that: The spacing groove is substantially U-shaped.

6. The current collecting sheet according to claim 1, characterized in that: The through holes are arranged linearly.

7. The current collecting sheet according to claim 6, characterized in that: The spacing groove includes linear branch grooves directly facing each of the through holes.

8. The current collecting sheet according to claim 1, characterized in that: The current collecting sheet includes two wing portions, which are respectively connected to opposite ends of the shell welding area.

9. The current collecting sheet according to any one of claims 1 to 8, characterized in that: The current collecting sheet is formed by slotting a strip sheet.

10. A power battery, characterized in that: It comprises the current collecting sheet as claimed in any one of claims 1 to 9.

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