Collector plate for power battery and power battery

Abstract

The utility model discloses a current collector plate for power battery and power battery, current collector plate includes main part and extension part, the extension part is formed by extending and bending one side edge of main part, and the extension part is provided with a second boss protruding back to the main part and a sinking groove located below the second boss through stamping. And a third boss extending into the sinking groove is formed on the main body part through stamping. The lower side space of the first boss can be filled with the second boss so that the second boss can be attached to the first boss for welding, and the third boss can be attached to and support the lower side of the second boss, so that the thickness of a welding area for laser penetration welding of the current collecting disc and the first boss is increased through the double-layer structure; therefore, damage to the roll core due to the fact that the welding area is thin and broken down can be avoided, and the problem of point discharge caused by the fact that the bending position between the main body part and the extension part is squashed can be avoided.

Description

Technical Field

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

[0002] Currently, lithium-ion / sodium-ion cylindrical power batteries are becoming the mainstream products in the new energy industry due to their high energy density, good capacity consistency, and ability to support high-rate charge and discharge. More and more manufacturers are continuously pursuing structural compactness optimization of cylindrical power batteries to increase energy density. However, cylindrical power batteries currently have the following problems with the current collector:

[0003] (1) The bottom of many cylindrical power batteries is stamped outward to form a boss. However, the thickness of the current collector with a single bend is not enough to fill the depth of the groove under the boss, making it difficult to assemble. Moreover, there is a risk that the bend will be crushed during assembly, resulting in tip discharge.

[0004] (2) It is difficult to avoid damaging the core when conventional single-layer collector disc is welded to the shell bottom by laser penetration welding. Utility Model Content

[0005] The purpose of the present utility model is to provide a current collecting plate for a power battery and a power battery, which can solve at least one technical problem mentioned in the background technology.

[0006] In order to achieve the above-mentioned purpose, the utility model provides a collecting tray for a power battery, wherein the power battery includes a shell and a winding core sleeved in the shell, the collecting tray is welded between the shell bottom and the full pole ear of the winding core, and the middle part of the shell bottom is punched outward to form a first boss, characterized in that the collecting tray includes a main body and an extension part, the extension part is arranged facing the main body, the extension part is formed by extending and bending one side of the main body, a second boss protruding back to the main body and a sink located below the second boss are formed on the extension part by stamping, a third boss extending into the sink is formed on the main body by stamping, the second boss is configured to be welded to the inner side of the first boss by laser penetration welding, and the third boss is configured to fit the side of the second boss facing away from the first boss during laser penetration welding.

[0007] Optionally, the height of the third boss is greater than or equal to the depth of the sink.

[0008] Optionally, the second boss and the third boss are circular, and the diameter of the second boss is larger than the diameter of the third boss.

[0009] Optionally, the main body has a first side, a position of the first side extends outward to form a protruding portion, the end of the protruding portion is connected to a bending portion, the extension portion extends from the end of the bending portion, and the protruding portion and the bending portion are elastically deformable.

[0010] Optionally, the bent portion is U-shaped.

[0011] Optionally, two through grooves are spaced apart from each other on the main body, one end of the through groove passes through the first side edge, and the other end of the through groove extends toward a side away from the first side edge, and the two through grooves are separated into connecting arms, and the protruding portion is formed by the outward extension of the connecting arm, and the connecting arm and the protruding portion form an elastic arm that can be elastically deformed.

[0012] Optionally, the main body is strip-shaped and has approximately the same width along its length direction. The first side is a side of the main body in the width direction, and the length of the through groove in the width direction is 1 / 4 to 1 / 2 of the overall width of the main body.

[0013] Optionally, two through grooves are set at intervals on the main body, one end of the through groove passes through one side of the main body, and the other end of the through groove extends to the side away from the side, and the two through grooves are separated into elastically deformable connecting arms, and the extension part is formed by extending and bending the end of the connecting arm.

[0014] Optionally, the main body is strip-shaped, comprising a middle region in its length direction and tab welding areas on both sides of the middle region, the third boss is formed in the middle region, and the extension portion is formed by extending and bending the side of the middle region.

[0015] In order to achieve the above-mentioned purpose, the utility model also provides a power battery, including a winding core, a shell and a current collecting plate as described above, the winding core is arranged in the shell, the middle part of the shell bottom is punched outward to form a first boss, the current collecting plate is welded between the full pole ear of the winding core and the shell bottom, the main body is welded to the full pole ear of the winding core, and the second boss is welded to the inner side of the first boss by laser penetration welding.

[0016] In an embodiment of the present invention, a second boss protruding away from the main body and a recessed groove below the second boss are formed on the extension portion by stamping. A third boss extending into the recessed groove is formed on the main body by stamping. The second boss is configured to be welded to the inner side of the first boss by laser penetration welding, and the third boss is configured to fit the side of the second boss away from the first boss during laser penetration welding. As can be seen, the second boss can fill the lower space of the first boss to fit with the first boss for welding, and because the third boss can fit and support the lower side of the second boss, the double-layer structure can be used to increase the thickness of the welding area between the collector plate and the first boss for laser penetration welding, which is beneficial to avoid damage to the winding core due to breakdown of the thin welding area, and is also beneficial to avoid the problem of tip discharge caused by the bending part between the main body and the extension being crushed. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the three-dimensional structure of the collecting plate of an embodiment of the utility model.

[0018] Figure 2 It is a schematic diagram of the three-dimensional structure of the collecting plate of an embodiment of the utility model from another perspective.

[0019] Figure 3 It is a schematic cross-sectional structural diagram of the current collecting plate according to an embodiment of the present utility model.

[0020] Figure 4 It is a schematic diagram of the three-dimensional structure of the collecting plate assembled to the winding core according to an embodiment of the present invention.

[0021] Figure 5 It is a three-dimensional structural schematic diagram of another perspective of the current collecting plate assembled to the winding core in an embodiment of the utility model.

[0022] Figure 6 It is a schematic cross-sectional structure diagram of a power battery according to an embodiment of the present utility model. DETAILED DESCRIPTION

[0023] In order to explain the technical content, structural features and achieved effects of the present invention in detail, the following is a detailed description in conjunction with the embodiments and the accompanying drawings.

[0024] To make the above-mentioned objects, features, and advantages of the present invention more clearly understood, the following detailed description of specific embodiments of the present invention is provided in conjunction with the accompanying drawings. The following description sets forth many specific details to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art may make similar modifications without departing from the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0025] Example 1

[0026] See also Figures 1 to 6 The utility model discloses a current collecting tray 1 for a power battery. The power battery includes a shell 5 and a winding core 4 sleeved in the shell 5. The current collecting tray 1 is welded between the shell bottom 51 of the shell 5 and the full-pole lug of the winding core 4. The middle part of the shell bottom 51 is punched outward to form a first boss 511. The current collecting tray 1 includes a main body 10 and an extension 20. The extension 20 is arranged facing the main body 10. The extension 20 is formed by extending and bending one side of the main body 10. A second boss 21 protruding away from the main body 10 and a recessed groove 22 located below the second boss 21 are formed on the extension 20 by stamping. A third boss 11 extending into the recessed groove 22 is formed on the main body 10 by stamping. The second boss 21 is configured to be welded to the inner side of the first boss 511 by laser penetration welding. The third boss 11 is configured to adhere to the side of the second boss 21 away from the first boss 511 during laser penetration welding.

[0027] In the embodiment of the present invention, a second boss 21 projecting away from the main body 10 and a recessed groove 22 located below the second boss 21 are formed by stamping on the extension portion 20. A third boss 11 extending into the recessed groove 22 is also stamped on the main body 10. The second boss 21 is configured to be welded to the inner side of the first boss 511 by laser penetration welding. The third boss 11 is configured to abut the side of the second boss 21 facing away from the first boss 511 during laser penetration welding. Thus, the second boss 21 can fill the space below the first boss 511 to abut against the first boss 511 for welding. Furthermore, because the third boss 11 can abut against and support the lower side of the second boss 21, the double-layer structure can increase the thickness of the weld area between the collecting plate 1 and the first boss 511 during laser penetration welding. This helps avoid damage to the winding core 4 due to breakdown in the thin weld area and also helps avoid tip discharge caused by the collapse of the bend between the main body 10 and the extension portion 20.

[0028] In some embodiments, the height of the third boss 11 is greater than or equal to the depth of the recess 22. Specifically, the height of the third boss 11 may be slightly greater than the depth of the recess 22. This configuration enables the third boss 11 to better support the second boss 21.

[0029] In some embodiments, the second boss 21 and the third boss 11 are circular, with the diameter of the second boss 21 being larger than that of the third boss 11. This larger diameter of the second boss 21 facilitates the fit and support of the third boss 11 against the underside of the second boss 21. Of course, the shapes of the second boss 21 and the third boss 11 are not limited to circular; they can also be other shapes, such as elliptical, and are not limited to being the same shape.

[0030] In some embodiments, the main body 10 has a first side 12, a portion of the first side 12 extending outwardly to form a protruding portion 131. The distal end of the protruding portion 131 is connected to a bent portion 30, and the extension 20 extends from the distal end of the bent portion 30. The protruding portion 131 and the bent portion 30 are elastically deformable. Because the protruding portion 131 and the bent portion 30 are elastically deformable, the position of the bent portion 30 can be adaptively adjusted (changed) when subjected to pressure, preventing the risk of the bent portion 30 being crushed and causing tip discharge, and ensuring the ability to rely on elastic deformation to dissipate stress in situations such as vehicle loading vibration.

[0031] Specifically, the bent portion 30 is U-shaped, but is not limited thereto.

[0032] It should be noted that the U-shape herein 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 all fall within the U-shape referred to in the present invention, such as arc-shaped, parabolic-shaped, and the like.

[0033] Specifically, two through-grooves 14 are provided on the main body 10 at intervals. One end of the through-grooves 14 passes through the first side 12, and the other end of the through-grooves 14 extends toward a side away from the first side 12. The two through-grooves 14 are separated into a connecting arm 13. The protrusion 131 is formed by the outward extension of the connecting arm 13. The connecting arm 13 and the protrusion 131 form an elastically deformable elastic arm. By setting the two through-grooves 14 at intervals, the connecting arm 13 and the protrusion 131 form an elastically deformable elastic arm. The elastic arm has a longer length than the protrusion 131 without changing the overall size of the current collecting plate 1, so that the position of the bent portion 30 can be better adaptively adjusted (the position changes) when subjected to pressure, which can better prevent the risk of the bent portion 30 being crushed and causing tip discharge. In addition, it can better ensure that the impact stress is released by elastic deformation under conditions such as vehicle loading vibration, thereby improving the anti-seismic performance of the power battery.

[0034] Specifically, the main body 10 is strip-shaped and has a substantially uniform width along its length. The first side 12 is a side of the main body 10 in the width direction, and the length of the through-groove 14 in the width direction is 1 / 4 to 1 / 2 of the overall width of the main body 10. Due to the strip-shaped main body 10, the material used can be significantly reduced compared to the commonly used complex collecting tray 1, further contributing to lower production costs.

[0035] In some embodiments, the main body 10 is provided with two through-grooves 14 spaced apart, one end of the through-grooves 14 passing through one side of the main body 10, and the other end of the through-grooves 14 extending away from the side. The two through-grooves 14 are separated into an elastically deformable connecting arm 13, and the extension 20 is formed by extending and bending the end of the connecting arm 13. By spacing the two through-grooves 14 apart, the two through-grooves 14 are separated into an elastically deformable connecting arm 13. Based on the formation of the connecting arm 13, the position of the bent portion 30 connected between the connecting arm 13 and the extension 20 can be adaptively adjusted (the position changes), which helps to prevent the risk of the bent portion 30 being crushed and causing tip discharge, thereby better ensuring that the impact stress is released by elastic deformation under conditions such as vehicle loading vibration, thereby improving the anti-seismic performance of the power battery.

[0036] In some embodiments, the main body 10 is strip-shaped, and the main body 10 includes a middle area 15 in its length direction and tab welding areas 16 located on both sides of the middle area 15. The third boss 11 is formed in the middle area 15, and the extension portion 20 is formed by extending and bending the side of the middle area 15.

[0037] Furthermore, the tab welding area 16 forms at least one welding track 17, which is used to conduct at least part of the entire tab from the inner ring to the outer ring of the winding core 4. The welding track 17 can have a straight or spiral appearance, etc., which is not limited.

[0038] Specifically, a welding track 211 with a spiral appearance is formed on the second boss 21 , but the present invention is not limited thereto.

[0039] Example 2

[0040] See also Figures 1 to 6 The present utility model also discloses a power battery, including a winding core 4, a shell 5 and the collecting plate 1 as described above. The winding core 4 is sleeved in the shell 5. The middle part of the shell bottom 51 of the shell 5 is punched outward to form a first boss 511. The collecting plate 1 is welded between the full tab of the winding core 4 and the shell bottom 51. The main body 10 is welded to the full tab of the winding core 4. The second boss 21 is welded to the inner side of the first boss 511 by laser penetration welding.

[0041] In an embodiment of the present utility model, a second boss 21 protruding away from the main body 10 and a recessed groove 22 located below the second boss 21 are formed on the extension portion 20 of the collecting plate 1 by stamping, and a third boss 11 extending into the recessed groove 22 is formed on the main body 10 by stamping. The second boss 21 is configured to be welded to the inner side of the first boss 511 by laser penetration welding, and the third boss 11 is configured to fit the side of the second boss 21 away from the first boss 511 during laser penetration welding. It can be seen that the second boss 21 can fill the lower space of the first boss 511 to fit with the first boss 511 for welding, and since the third boss 11 can fit and support the lower side of the second boss 21, the double-layer structure can be used to increase the thickness of the welding area between the collecting plate 1 and the first boss 511 for laser penetration welding, which is beneficial to avoid damage to the winding core 4 due to breakdown due to the thin welding area, and is also beneficial to avoid the tip discharge problem caused by the bending part between the main body 10 and the extension part 20 being compressed.

[0042] To facilitate a better understanding of the present invention, the following briefly describes an optional assembly process of a power battery based on an example of the accompanying drawings:

[0043] First, the second boss 21 of the extension portion 20 and the third boss 11 of the main portion 10 are punched out according to a preset size, and then bent so that the extension portion 20 faces the main portion 10;

[0044] Next, the entire tab of the winding core 4 is pre-treated by flattening / patting;

[0045] Next, fit the main body 10 of the collector plate 1 to the full tab of the winding core 4 so that the third boss 11 of the collector plate 1 corresponds to the winding core through hole 41 of the winding core 4;

[0046] Next, the main body 10 of the collecting plate 1 is welded to the full tab of the winding core 4;

[0047] Next, place the winding core 4 into the housing 5 with the extension 20 facing the housing bottom 51;

[0048] Next, a clamp is used to support the winding core 4 and the third boss 11, so that the third boss 11 is fitted with the second boss 21, and the second boss 21 is fitted with the first boss 511 of the shell bottom 51. During this process, the presence of the elastic arm can enable the position of the bent portion 30 to be adaptively adjusted.

[0049] Next, the first boss 511 is welded to the second boss 21 by laser penetration welding from the outside of the shell bottom 51 .

[0050] The above disclosure is only a preferred example of the present invention, and its role is to facilitate the understanding and implementation of those skilled in the art. It certainly cannot be used to limit the scope of rights of the present invention. Therefore, equivalent changes made within the scope of the patent application of the present invention still fall within the scope covered by the present invention.

Claims

1. A current collecting tray for a power battery, comprising a housing and a winding core sleeved within the housing, wherein the current collecting tray is welded between the bottom of the housing and the full tab of the winding core, and wherein the middle portion of the bottom of the housing is punched outward to form a first boss, characterized in that: The collecting plate includes a main body and an extension portion, the extension portion is arranged facing the main body, and the extension portion is formed by extending and bending one side of the main body. A second boss protruding away from the main body and a recessed groove located below the second boss are formed on the extension portion by stamping. A third boss extending into the recessed groove is formed on the main body by stamping. The second boss is configured to be welded to the inner side of the first boss by laser penetration welding, and the third boss is configured to fit the side of the second boss facing away from the first boss during laser penetration welding.

2. The collecting plate according to claim 1, characterized in that: The height of the third boss is greater than or equal to the depth of the sink.

3. The collecting plate according to claim 1, characterized in that: The second boss and the third boss are circular, and the diameter of the second boss is greater than the diameter of the third boss.

4. The collecting plate according to claim 1, characterized in that: The main body has a first side, a position of the first side extends outward to form a protruding portion, the end of the protruding portion is connected to a bent portion, the extension portion extends from the end of the bent portion, and the protruding portion and the bent portion are elastically deformable.

5. The collecting plate according to claim 4, characterized in that: The bent portion is U-shaped.

6. The collecting plate according to claim 4, characterized in that: The main body is provided with two through grooves spaced apart from each other, one end of the through groove passes through the first side edge, and the other end of the through groove extends toward a side away from the first side edge. The two through grooves are separated into connecting arms, and the protruding portion is formed by the outward extension of the connecting arm, and the connecting arm and the protruding portion form an elastic arm that can be elastically deformed.

7. The collecting plate according to claim 6, characterized in that: The main body is strip-shaped and has approximately the same width along its length. The first side is one side of the main body in the width direction. The length of the through groove in the width direction is 1 / 4 to 1 / 2 of the overall width of the main body.

8. The collecting plate according to claim 1, characterized in that: The main body is provided with two through grooves spaced apart from each other, one end of the through groove passes through one side of the main body, and the other end of the through groove extends to a side away from the side, and the two through grooves are separated into elastically deformable connecting arms, and the extension portion is formed by extending and bending the end of the connecting arm.

9. The collecting plate according to claim 1, characterized in that: The main body is strip-shaped and includes a middle region in its length direction and tab welding areas on both sides of the middle region. The third boss is formed in the middle region, and the extension portion is formed by extending and bending the side of the middle region.

10. A power battery, characterized in that: It includes a winding core, a shell and a collecting disk as described in any one of claims 1 to 9, the winding core is sleeved in the shell, the middle part of the shell bottom is punched outward to form a first boss, the collecting disk is welded between the full pole ear of the winding core and the shell bottom, the main body is welded to the full pole ear of the winding core, and the second boss is welded to the inner side of the first boss by laser penetration welding.

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