Current collecting plate structure for cylindrical power battery and cylindrical power battery

Abstract

The present application discloses a current collecting plate structure for a cylindrical power battery and a cylindrical power battery. The current collecting plate structure includes a current collecting plate and a limiting column. The current collecting plate includes a main body, an extension and a bending part. The extension faces the main body and is connected to the edge of the main body through the bending part. The limiting column is arranged in the inner space of the bending part to support the bending part. In the present application, the support of the limiting column can prevent the bending part from being crushed or deformed, thereby helping to avoid the risk of tip discharge when the battery is charged and discharged with overcurrent.

Description

Technical Field

[0001] The present application relates to the technical field of power batteries, and in particular to a current collecting plate structure for a cylindrical power battery and a power battery. Background Art

[0002] At present, cylindrical power batteries such as lithium-ion / sodium-ion batteries have gradually become mainstream products in the new energy vehicle and energy storage industries due to their high energy density, good capacity consistency, and support for high-rate charging and discharging. More and more manufacturers continue to pursue the optimization of the compactness of cylindrical power battery structures to improve energy density.

[0003] However, the current collector of cylindrical power batteries currently has the following problems:

[0004] When resistance welding is performed on the collector plate of a cylindrical power battery, if a pure nickel collector plate is used, the price is relatively high and the resistance is relatively high (resulting in a large temperature rise during current flow, posing a safety risk). If an aluminum-nickel composite strip or a copper-nickel composite strip collector plate is used, the problem of needle sticking cannot be avoided when the aluminum or copper surface is facing upward and in contact with the welding needle.

[0005] In response to this technical problem, the patent application with application number 2024202137559 and patent name "Current collector for power battery and power battery" proposed a solution of bending the current collector into an O-shape or U-shape. However, this solution has the following problems: if the bend is sharp or the bend is crushed after the battery is installed on the vehicle, it is easy to cause the risk of tip discharge when the power battery is charged and discharged with overcurrent, affecting the normal charging and discharging of the power battery, and the battery temperature rise brings safety risks. Summary of the invention

[0006] The purpose of the present application is to provide a current collecting plate structure for a cylindrical power battery and a cylindrical power battery, which can solve at least one technical problem mentioned in the background technology.

[0007] In order to achieve the above-mentioned objectives, the present application provides a current collecting plate structure for a cylindrical power battery, including a current collecting plate and a limiting column, the current collecting plate including a main body, an extension portion and a bending portion, the extension portion faces the main body and is connected to the edge of the main body through the bending portion; the limiting column is arranged in the inner space of the bending portion to support the bending portion.

[0008] Optionally, the limiting column is a limiting tube.

[0009] Optionally, two ends of the limiting tube extend beyond two ends of the bending portion and are claw-shaped and open to form outwardly expanding portions, and the outwardly expanding portions at both ends limit the limiting tube from sliding out of the inner space of the bending portion.

[0010] Optionally, two ends of the limiting column exceed two ends of the bending portion and form a stop structure, and the stop structures at both ends limit the limiting tube from sliding out of the inner space of the bending portion.

[0011] Optionally, the limiting column is cylindrical.

[0012] Optionally, the limiting column is at least partially in contact with the bending portion.

[0013] Optionally, the limiting column and the bending portion are adapted to be installed.

[0014] Optionally, the limiting column has electrical and / or thermal conductivity.

[0015] Optionally, the bending portion is elastically deformable.

[0016] Optionally, the bending portion is U-shaped.

[0017] Optionally, the collecting plate is formed of a sheet of copper-nickel or aluminum-nickel composite material, and the side of the extension portion facing away from the main body portion is a nickel layer and is configured to face the winding core through hole for contact by a welding pin.

[0018] Optionally, a through hole is formed on the main body, the through hole is configured to correspond to the through hole of the winding core for the soldering pin to pass through, and the extension portion faces the through hole.

[0019] Optionally, the collecting plate is formed of a sheet of copper-nickel or aluminum-nickel composite material, the side of the main body facing away from the extension part is a copper layer or an aluminum layer, and the side facing the extension part is a nickel layer, the side of the extension part facing away from the main body is a copper layer or an aluminum layer, and the side facing the main body is a nickel layer.

[0020] In order to achieve the above-mentioned purpose, the present application also provides a cylindrical power battery, including a winding core, a shell and a current collecting plate structure as described above, wherein the winding core is sleeved in the shell, and the current collecting plate is welded between the full pole ear of the winding core and the shell bottom of the shell.

[0021] In the present application, a limiting column is arranged in the inner space of the bending portion to support the bending portion. When the bending portion is impacted due to reasons such as the vibration of loading causing the winding core to drive the collecting plate to jump, the support of the limiting column can prevent the bending portion from being crushed or deformed, thereby helping to avoid the risk of tip discharge during battery charging and discharging overcurrent. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the three-dimensional structure of the collecting plate structure of an embodiment of the present application.

[0023] Figure 2 It is a schematic diagram of the exploded structure of the collecting plate structure of an embodiment of the present application.

[0024] Figure 3 It is a schematic diagram of the structure of the current collecting plate of an embodiment of the present application.

[0025] Figure 4 It is a schematic diagram of the cross-sectional structure of the current collecting plate of the embodiment of the present application.

[0026] Figure 5 It is a schematic diagram of the structure of the limiting column in the embodiment of the present application.

[0027] Figure 6 It is a schematic diagram of the cross-sectional structure of the limiting column of the embodiment of the present application.

[0028] Figure 7 It is a schematic diagram of the cross-sectional structure of the cylindrical power battery of the embodiment of the present application.

[0029] Figure 8 It is a schematic diagram of the exploded structure of the collecting plate structure of another embodiment of the present application.

[0030] Fig. 9 It is a schematic diagram of the three-dimensional structure of a current collecting plate according to another embodiment of the present application.

[0031] Fig.10 It is a schematic diagram of the cross-sectional structure of a cylindrical power battery according to another embodiment of the present application. DETAILED DESCRIPTION

[0032] 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.

[0033] 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.

[0034] See also Figures 1 to 10 , the embodiment of the present application discloses a current collecting plate structure for a cylindrical power battery. The current collecting plate structure includes a current collecting plate 1 and a limiting column 2. The current collecting plate 1 includes a main body 11, an extension 12 and a bending portion 13. The extension 12 faces the main body 11 and is connected to the edge of the main body 11 through the bending portion 13; the limiting column 2 is arranged in the inner space 131 of the bending portion 13 to support the bending portion 13. It can be understood that the current collecting plate 1 can be either a positive current collecting plate or a negative current collecting plate.

[0035] In the present application, a limiting column 2 is provided in the inner space 131 of the bending portion 13 to support the bending portion 13. When the bending portion 13 is impacted due to the vibration of loading causing the winding core 7 to drive the collecting plate 1 to jump, the support of the limiting column 2 can prevent the bending portion 13 from being crushed or deformed, thereby helping to avoid the risk of tip discharge during overcurrent charging and discharging of the battery.

[0036] In some embodiments, the limiting column 2 is a limiting tube 2, but is not limited thereto. Specifically, the limiting tube 2 is cylindrical, but of course, the limiting tube 2 is not limited to a cylindrical shape. In addition, it should be noted that the limiting tube 2 is cylindrical, which is not limited to the limiting tube 2 being cylindrical as a whole. It can be cylindrical as a whole, or include a main structure that is cylindrical.

[0037] Specifically, the two ends of the limiting tube 2 exceed the two ends of the bending portion 13 and are claw-shaped and open to form the outer expansion portion 21. The outer expansion portions 21 at the two ends restrict the limiting tube 2 from sliding out of the inner space 131 of the bending portion 13, so that the limiting tube 2 can be more reliably installed in the inner space 131 of the bending portion 13. Of course, the structure for restricting the limiting tube 2 from sliding out of the inner space 131 of the bending portion 13 is not limited to this form. In addition, the two ends of the limiting tube 2 do not necessarily form a structure for restricting the limiting tube 2 from sliding out of the inner space 131 of the bending portion 13.

[0038] In some embodiments, the limiting column 2 is cylindrical, of course, the limiting column 2 is not limited to a cylindrical shape. In addition, it should be noted that the limiting column 2 is cylindrical, which is not limited to the limiting column 2 being cylindrical as a whole, and it can be cylindrical as a whole, or include a main structure in a cylindrical shape.

[0039] In some embodiments, both ends of the limiting column 2 exceed both ends of the bending portion 13 and are formed with stop structures 21, and the stop structures 21 at both ends limit the limiting tube 2 from sliding out of the inner space 131 of the bending portion 13, so that the limiting column 2 can be more reliably installed in the inner space 131 of the bending portion 13. Of course, limiting the limiting column 2 from sliding out of the inner space 131 of the bending portion 13 is not limited to this form, and in addition, the two ends of the limiting column 2 do not necessarily form a structure that limits the limiting column 2 from sliding out of the inner space 131 of the bending portion 13.

[0040] In some embodiments, the limiting column 2 is at least partially in contact with the bent portion 13 , thereby facilitating installation reliability of the limiting column 2 .

[0041] Specifically, the limiting column 2 and the bending portion 13 are adapted to be installed. In a specific example, an arc-shaped side wall 132 is formed inside the bending portion 13 , and the limiting column 2 is cylindrical and adapted to the arc-shaped side wall 132 inside the bending portion 13 .

[0042] Specifically, the limiting column 2 has electrical and / or thermal conductivity. Since the limiting column 2 has electrical and / or thermal conductivity, it can play an auxiliary role in guiding and / or dissipating heat by contacting the bending portion 13, thereby avoiding safety risks caused by local high temperature.

[0043] In some embodiments, the bending portion 13 is U-shaped, but it is not limited to this. In addition, the U-shape here should not be understood in a narrow sense, such as the two arms of the U-shaped structure must be parallel. Various U-shaped structures should belong to the U-shape referred to in this application, such as arc shape, parabola shape, etc. For example, Figure 3 An example is provided in which the bent portion 13 has an arc shape.

[0044] See also Figures 1 to 7 In some embodiments, the extension portion 12 is configured to face the winding core through hole 71 for contact with the welding needle, and the extension portion 12, the main body 11 and the shell bottom 81 can be welded together by the welding needle. The extension portion 12 and the main body 11 are at least partially attached.

[0045] Specifically, the current collecting plate 1 is formed of a copper-nickel or aluminum-nickel composite sheet, and the side of the extension portion 12 facing away from the main body 11 is a nickel layer for the welding needle to contact. The nickel layer contacts the welding needle, which can avoid the problem of needle sticking.

[0046] Specifically, the main body 11 includes a middle welding area 111 and two wing welding areas 112 connected to both sides of the middle welding area 111. The extension 12 is connected to the middle welding area 111 through the bending portion 13 and faces the middle welding area 111. Under the action of the welding needle, the extension 12, the middle welding area 111 and the shell bottom 81 are welded together. The two wing welding areas 112 are welded to the full pole ear at one end of the winding core 7.

[0047] In order to release the possible stress, two L-shaped grooves 113 are formed on the main body 11 , and the wing welding area 112 is roughly U-shaped through the L-shaped grooves 113 , with a free end spaced apart from the middle welding area 111 .

[0048] Specifically, the middle welding area 111 is sunken compared to the two wing welding areas 112 , and the extension portion 12 and the two wing welding areas 112 are substantially located in the same plane.

[0049] See also Figures 8 to 10 In other embodiments, the side of the main body 11 facing away from the extension 12 is configured to be welded to the full pole tab of the winding core 7, and the side of the extension 12 facing away from the main body 11 is configured to be welded to the shell bottom 81. Specifically, the bending portion 13 can be elastically deformed. Of course, the bending portion 13 is not limited to being elastically deformable.

[0050] Specifically, a through hole 114 is formed on the main body 11, and the through hole 114 is configured to correspond to the winding core through hole 71 for the welding needle to pass through, and the extension 12 faces the through hole 114. Since the through hole 114 corresponding to the winding core through hole 71 is provided on the main body 11, and the extension 12 faces the through hole 114, when the collector plate 1 and the full pole ear of the winding core 7 are welded and assembled into the shell 8, the welding needle can be used to pass through the winding core through hole 71 and the through hole 114 to perform resistance welding on the extension 12 and the shell bottom 81. It can be understood that the extension 12 and the shell bottom 81 are not limited to being welded by resistance welding.

[0051] Specifically, the diameter of the through hole 114 is greater than the diameter of the winding core through hole 71 .

[0052] Specifically, the main body 11 is generally rectangular in shape, the through hole 114 is located in the middle of the main body 11 in the length direction, and the main body 11 has a lug welding area 112 formed on both sides of the through hole 114 in the length direction for welding to the full lug of the winding core 7, and the bending portion 13 extends from an edge in the width direction of the main body 11.

[0053] Furthermore, both sides of the extension portion 12 in the length direction of the main body 11 exceed the through hole 114, and the projection of the extension portion 12 on the main body 11 completely covers the through hole 114, thereby facilitating reliable resistance welding. Of course, this is not limited to this.

[0054] Specifically, the collector plate 1 is formed by bending a sheet of copper-nickel composite material. The so-called copper-nickel composite material sheet is a sheet formed by superimposing a copper layer and a nickel layer. After the collector plate 1 is formed by bending, the side of the main body 11 facing away from the extension part 12 is a copper layer, and the side facing the extension part 12 is a nickel layer. The side of the extension part 12 facing away from the main body 11 is a copper layer, and the side facing the main body 11 is a nickel layer. Since the side of the main body 11 facing away from the extension part 12 is a copper layer, it is convenient to weld with the full pole ear of the winding core 7 (specifically laser welding), and the side of the extension part 12 facing away from the main body 11 is a copper layer, which is convenient for welding with the shell bottom 81, and the problem of high resistance between the nickel layer and the shell bottom 81 can be solved. The side of the extension part 12 facing the main body 11 is a nickel layer, and then when the extension part 12 and the shell bottom 81 are resistance welded by a welding needle, the occurrence of the needle sticking problem can be avoided. Further, the shell 8 is a steel shell 8.

[0055] Specifically, the collector plate 1 is formed by bending a sheet of aluminum-nickel composite material, and the so-called aluminum-nickel composite material sheet is a sheet formed by stacking an aluminum layer and a nickel layer. After the collector plate 1 is formed by bending, the side of the main body 11 facing away from the extension part 12 is an aluminum layer, and the side facing the extension part 12 is a nickel layer. The side of the extension part 12 facing away from the main body 11 is an aluminum layer, and the side facing the main body 11 is a nickel layer. Since the side of the main body 11 facing away from the extension part 12 is an aluminum layer, it is convenient to weld with the full pole ear of the winding core 7 (specifically laser welding), and the side of the extension part 12 facing away from the main body 11 is an aluminum layer, which is convenient to weld with the shell bottom 81, which can solve the problem of high resistance of the nickel layer and the shell bottom 81. The side of the extension part 12 facing the main body 11 is a nickel layer, and then when the extension part 12 and the shell bottom 81 are resistance welded by using a welding needle, the occurrence of the needle sticking problem can be avoided. Further, the shell 8 is an aluminum shell 8.

[0056] In some embodiments, the collecting tray 1 can be formed by bending the sheet material before receiving the material.

[0057] In some embodiments, the extension portion 12 is parallel to the main body portion 11. However, this is not a limitation. It should be explained that the extension portion 12 and the main body portion 11 are parallel when they are in a natural state.

[0058] The extension part 12 and the main body 11 may be spaced apart or may be attached to each other. It should be noted that, here, the extension part 12 and the main body 11 are attached to each other not limited to being attached to the whole, but may also be attached to each other partially.

[0059] In the above embodiments, examples are given of the collector plate 1 being welded between the full pole ear of the winding core 7 and the shell bottom 81. This is not limited to this. The collector plate can also be set at the other end of the winding core 7 to weld the full pole ear of the winding core 7 to the relevant structure. In summary, this application does not limit the use of the collector plate, nor is it limited to the welding object of the extension part and the main body. The protection focus is on the setting of the limit column in the bending part.

[0060] Please combine Figures 1 to 10 The present application also discloses a cylindrical power battery, including a winding core 7, a shell 8 and a current collecting plate structure as described above, wherein the winding core 7 is sleeved in the shell 8, and the current collecting plate 1 is welded between the full pole ear of the winding core 7 and the shell bottom 81 of the shell 8.

[0061] In the present application, a limiting column 2 is provided in the inner space 131 of the bending portion 13 to support the bending portion 13. When the bending portion 13 is impacted due to the vibration of loading causing the winding core 7 to drive the collecting plate 1 to jump, the support of the limiting column 2 can prevent the bending portion 13 from being crushed or deformed, thereby helping to avoid the risk of tip discharge during overcurrent charging and discharging of the battery.

[0062] The following describes an optional assembly process of the exemplary cylindrical power battery of the present application to facilitate understanding of the present application and should not be regarded as a limitation of the present application.

[0063] First, before the current collecting plate 1 is bent, the limiting column 2 is placed at the position of the current collecting plate 1 to be bent to assist the current collecting plate 1 in bending, thereby forming a relatively arranged main body portion 11 and an extension portion 12 and a bending portion 13 connecting the main body portion 11 and the extension portion 12; alternatively, after the current collecting plate 1 is bent, the limiting column 2 is placed in the inner space 131 of the bending portion 13.

[0064] Thereafter, different assembly steps may be performed according to different embodiments.

[0065] based on Figures 1 to 7 The example shown can be followed by the following assembly steps:

[0066] The two wing welding areas 112 of the current collecting plate 1 are attached and welded to the full pole ears of the winding core 7, and the extension part 12 faces the winding core through hole 71;

[0067] Place the winding core 7 into the housing 8;

[0068] A welding needle is used to pass through the winding core through hole 71 to perform resistance welding on the extension portion 12 , the middle welding area 111 and the shell bottom 81 .

[0069] based on Figures 8 to 10 The example shown can be followed by the following assembly steps:

[0070] Fit the main body 11 of the collector plate 1 to the full pole ear of the winding core 7 so that the through hole 114 of the collector plate 1 corresponds to the winding core through hole 71 of the winding core 7;

[0071] Welding the main body 11 of the current collecting plate 1 to the full pole lug of the winding core 7;

[0072] Place the winding core 7 into the housing 8 so that the extension 12 faces the housing bottom 81;

[0073] After the welding needle is passed through the winding core through hole 71 and the through hole 114 in sequence, the extension portion 12 and the shell bottom 81 are resistance welded.

[0074] 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 plate structure for a cylindrical power battery, characterized in that: The device comprises a current collecting plate and a limiting column, wherein the current collecting plate comprises a main body, an extension portion and a bending portion, wherein the extension portion faces the main body and is connected to the edge of the main body through the bending portion; the limiting column is arranged in the inner space of the bending portion to support the bending portion; A through hole is formed on the main body, the through hole is configured to correspond to the through hole of the winding core for the solder pin to pass through, and the extension portion faces the through hole; The collecting plate is formed of a sheet of copper-nickel or aluminum-nickel composite material, the side of the main body facing away from the extension part is a copper layer or an aluminum layer, and the side facing the extension part is a nickel layer, the side of the extension part facing away from the main body is a copper layer or an aluminum layer, and the side facing the main body is a nickel layer.

2. The collecting plate structure according to claim 1, characterized in that: The limiting column is a limiting tube.

3. The collecting plate structure according to claim 2, characterized in that: The two ends of the limiting tube exceed the two ends of the bending part and are claw-shaped and opened to form an outward expansion part. The outward expansion parts at the two ends limit the limiting tube from sliding out of the inner space of the bending part.

4. The collecting plate structure according to claim 1 or 2, characterized in that: Two ends of the limiting column exceed two ends of the bending portion and form a stop structure, and the stop structures at both ends limit the limiting column from sliding out of the inner space of the bending portion.

5. The collecting plate structure according to claim 1 or 2, characterized in that: The limiting column is cylindrical.

6. The current collecting plate structure according to claim 1 or 2, characterized in that: The limiting column is at least partially in contact with the bending portion. 7 . The collecting plate structure according to claim 6 , wherein the limiting column and the bent portion are adapted to be installed. 8 . The current collecting plate structure according to claim 6 , wherein the limiting pillar has electrical and / or thermal conductivity.

9. The current collecting plate structure according to claim 1, characterized in that: The bent portion is elastically deformable.

10. The current collecting plate structure according to claim 1, characterized in that: The bent portion is U-shaped.

11. The current collecting plate structure according to claim 1, characterized in that: The collecting plate is formed of a copper-nickel or aluminum-nickel composite material sheet, and the side of the extension portion facing away from the main body portion is a nickel layer and is configured to face the winding core through hole for contact by a welding pin.

12. A cylindrical power battery, characterized in that: It comprises a winding core, a shell and a current collecting disk structure as claimed in any one of claims 1 to 11, wherein the winding core is sleeved in the shell, and the current collecting disk is welded between the full pole ear of the winding core and the shell bottom of the shell.

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