Power battery structure and assembly method thereof

Abstract

The invention discloses a power battery structure and an assembly method thereof. The power battery structure comprises a roll core, a collector plate and an insulating spacer, the collector plate comprises a welding plate part arranged on the upper side of the collector plate body in a protruding mode, and one position of the welding plate part is connected to the collector plate body through a fusing part. A first through groove and a second through groove are formed in the insulating spacer, when the insulating spacer is assembled on the collector plate main body, the welding plate part upwards passes through the first through groove and then relatively slides to the upper side of the second through groove, the two sides of the welding plate part are supported on the two sides of the insulating spacer in the second through groove, and the two ends of the fusing part are stopped by the two opposite side walls of the second through groove. When the power battery has abnormal high temperature, the fusing part can be burnt out to avoid safety risks brought to the battery. When the power battery abnormally burns out the fusing part, under the supporting and limiting effects of the insulating spacer, the safety risk caused by secondary connection after the fusing part is burnt out can be prevented.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a power battery structure and an assembly method thereof. Background Art

[0002] At present, lithium-ion / sodium-ion power batteries (such as cylindrical power batteries) have gradually become 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 prefer aluminum-shell cylindrical power batteries with shell-bottom penetration welding to achieve battery lightweighting and increase vehicle endurance, while taking into account consumers' daily needs for fast travel (high-rate battery charge and discharge). Frequently Asked Questions:

[0003] The power battery is equipped with a shell bottom (and collector plate) through-welding process. The collector plate and the shell bottom are in contact with a large area, making it difficult to implement a fuse (FUSE) design, which may bring safety risks to the power battery.

[0004] In addition, if the power battery is directly provided with a fuse structure on the current collecting plate, even if the power battery burns out when an abnormality occurs, the vibration can easily trigger a bridging connection (i.e., the location where the fuse structure burns out has a secondary electrical contact connection), causing the battery fuse structure to fail and bringing new safety risks. Summary of the invention

[0005] The purpose of the present application is to provide a power battery structure and an assembly method of the power battery structure, which can solve at least one technical problem in the above-mentioned background technology.

[0006] To achieve the above objectives, the present application provides a power battery structure, comprising:

[0007] A current collecting disc, the current collecting disc comprising a current collecting disc body and a welding plate portion protruding from the upper side of the current collecting disc body, the current collecting disc body being welded to the full-pole lug at one end of the winding core, and a position of the welding plate portion being connected to the current collecting disc body through a fuse;

[0008] An insulating gasket, wherein a first through groove and a second through groove are formed on the insulating gasket, the first through groove and the second through groove are connected, and when the insulating gasket is assembled to the collecting plate body, the welding plate portion passes upward through the first through groove and then slides relatively to the upper side of the second through groove, and both sides of the welding plate portion are supported by the insulating gasket on both sides of the second through groove, and both ends of the fuse portion are stopped by two opposite side walls of the second through groove.

[0009] In an embodiment of the present application, the current collecting disc includes a current collecting disc main body and a welding plate portion protruding from the upper side of the current collecting disc main body, the welding plate portion and the current collecting disc main body are connected by a fuse portion, and an insulating gasket is provided on the current collecting disc main body to separate it from the welding plate portion. When the power battery is abnormally high in temperature, the fuse portion can be burned out to avoid safety risks to the battery. Moreover, since the insulating gasket separates the current collecting disc main body and the welding plate portion from top to bottom, when the power battery abnormally burns out the fuse portion, the safety risks caused by secondary connection after the fuse portion is burned out can be prevented under the supporting and limiting action of the insulating gasket. In addition, in an embodiment of the present application, by providing the first through groove and the second through groove on the insulating gasket, the insulating gasket that separates the current collecting disc main body and the welding plate portion from top to bottom can be smoothly assembled on the current collecting disc.

[0010] Optionally, the fuse portion is connected to an outer edge of the welding plate portion, a spacing groove is formed between the outer edge of the welding plate portion and the current collecting plate body, and both ends of the spacing groove terminate at the fuse portion.

[0011] Optionally, the welding plate portion and the fuse portion are formed by punching and cutting the current collecting plate.

[0012] Optionally, the welding plate portion is circular, the first through groove is circular with one end open to connect to the second through groove, and the radius of the first through groove is greater than the radius of the welding plate portion.

[0013] Optionally, two opposite side walls of the second through slot gradually approach each other in a direction away from the first through slot.

[0014] Optionally, the welding plate portion is arranged corresponding to the middle portion of the winding core.

[0015] Optionally, a liquid injection through hole is formed on the welding plate portion, and the liquid injection through hole faces the second through groove.

[0016] Optionally, the power battery structure is a cylindrical power battery structure; the power battery structure also includes a shell, and the winding core, the collecting disk and the insulating gasket are sleeved in the shell; the outer edge of the insulating gasket is adapted to the side wall of the shell to be radially limited.

[0017] To achieve the above objectives, the present application also provides a method for assembling a power battery structure, comprising the following steps:

[0018] Welding the collector plate body onto the full pole lug of the winding core;

[0019] Align the first through slot of the insulating gasket with the welding plate portion, and then place the insulating gasket on the current collecting plate body, with the welding plate portion passing upward through the first through slot;

[0020] Slide the insulating gasket to make the welding plate part slide relatively to the upper side of the second through groove and the fuse part slide to the second through groove until the two ends of the fuse part are stopped by the two opposite side walls of the second through groove, and the two sides of the welding plate part are supported by the insulating gasket on both sides of the second through groove.

[0021] By means of the above assembly method, the insulating gasket separating the current collecting plate body and the welding plate portion can be smoothly assembled on the current collecting plate body to support and limit the welding plate portion, and is conducive to ensuring the structural strength of the insulating gasket, thereby ensuring the functional effect of the insulating gasket.

[0022] To achieve the above objectives, the present application also provides a method for assembling a power battery structure, comprising the following steps:

[0023] Welding the collector plate body onto the full pole lug of the winding core;

[0024] Align the first through slot of the insulating gasket with the welding plate portion, and then place the insulating gasket on the current collecting plate body, with the welding plate portion passing upward through the first through slot;

[0025] Sliding the insulating gasket, so that the welding plate portion slides relatively to the upper side of the second through slot and the fuse portion slides to the second through slot, until both ends of the fuse portion are stopped by two opposite side walls of the second through slot, and both sides of the welding plate portion are supported by the insulating gasket on both sides of the second through slot;

[0026] The winding core, the current collecting disk and the insulating gasket are inserted into the shell, and the side wall of the shell limits the insulating gasket in radial direction.

[0027] By means of the above-mentioned assembly method, the insulating gasket separating the collector plate body and the welding plate portion can be smoothly assembled on the collector plate body to support and limit the welding plate portion, and is conducive to ensuring the structural strength of the insulating gasket, thereby ensuring the functional effect of the insulating gasket. In addition, since the side wall of the shell will radially limit the insulating gasket, and the fuse portion is stopped and limited on the two opposite side walls of the second through groove, the circumferential limit of the insulating gasket can be achieved by the limiting effect of the fuse portion. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic cross-sectional structure diagram of the power battery structure of an embodiment of the present application.

[0029] Figure 2 It is a schematic diagram of the cross-sectional structure of the power battery structure of an embodiment of the present application after the shell is omitted.

[0030] Figure 3 It is a schematic diagram of the three-dimensional structure of the winding core and the collecting plate in the embodiment of the present application.

[0031] Figure 4 It is a schematic diagram of the three-dimensional structure of the current collecting plate and the insulating gasket in the embodiment of the present application.

[0032] Figure 5 It is a schematic diagram of the exploded structure of the current collecting plate and the insulating gasket in the embodiment of the present application.

[0033] Figure 6 It is a schematic diagram of the top view of the collecting plate of an embodiment of the present application.

[0034] Figure 7 It is a schematic diagram of the cross-sectional structure of the current collecting plate of the embodiment of the present application. DETAILED DESCRIPTION

[0035] 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.

[0036] See also Figures 1 to 7 The embodiment of the present application discloses a power battery structure, including a winding core 10, a current collecting plate 20 and an insulating gasket 30. The current collecting plate 20 includes a current collecting plate body 21 and a welding plate portion 22 protruding from the upper side of the current collecting plate body 21. The current collecting plate body 21 is welded to the full pole ear at one end of the winding core 10, and a position of the welding plate portion 22 is connected to the current collecting plate body 21 through a fuse portion 23. The insulating gasket 30 is provided with a first through slot 31 and a second through slot 32 that penetrate up and down. The first through slot 31 and the second through slot 32 are connected. When the insulating gasket 30 is assembled on the current collecting plate body 21, the welding plate portion 22 passes upward through the first through slot 31 and then slides relatively to the upper side of the second through slot 32. The two sides of the welding plate portion 22 are supported on the insulating gasket 30 on both sides of the second through slot 32, and the two ends of the fuse portion 23 are stopped by the two opposite side walls of the second through slot 32.

[0037] It should be explained that the two sides of the welding plate portion 22 are supported by the insulating gasket 30 on both sides of the second through groove 32, which does not mean that the welding plate portion 22 is only supported by the insulating gasket 30 on both sides of the second through groove 32. In the example in the accompanying drawings, the insulating gasket 30 forms a C-shaped support for the welding plate portion 22 in the outer area of ​​the second through groove 32.

[0038] In the embodiment of the present application, the current collecting disc 20 includes a current collecting disc main body 21 and a welding plate portion 22 protruding on the upper side of the current collecting disc main body 21, and the welding plate portion 22 and the current collecting disc main body 21 are connected by a fuse portion 23, and an insulating gasket 30 is provided on the current collecting disc main body 21 to separate it from the welding plate portion 22. When the power battery is abnormally high in temperature, the fuse portion 23 can be burned to avoid the safety risks brought to the battery. Moreover, since the insulating gasket 30 isolates the current collecting disc main body 21 and the welding plate portion 22 from top to bottom, when the power battery abnormally burns the fuse portion 23, the safety risk caused by the secondary connection after the fuse portion 23 is burned can be prevented under the supporting and limiting action of the insulating gasket 30. In addition, in the embodiment of the present application, by setting the first through groove 31 and the second through groove 32 on the insulating gasket 30, the insulating gasket 30 that isolates the current collecting disc main body 21 and the welding plate portion 22 from top to bottom can be smoothly assembled on the current collecting disc 20.

[0039] In some embodiments, the power battery structure is a cylindrical power battery structure, but is not limited thereto.

[0040] In some embodiments, the power battery structure further includes a shell 40 sleeved on the outside of the winding core 10. The welding plate portion 22 is welded to the inner side of the shell bottom 41 of the shell 40. Due to the support of the welding plate portion 22 by the insulating gasket 30, when penetration welding with the shell bottom 41 is required, it can ensure that the welding plate portion 22 is well fitted with the shell bottom 41 for penetration welding, and there is no need to use a clamp to support the welding plate portion 22, which is conducive to improving production efficiency.

[0041] Of course, the welding plate portion 22 is not limited to being welded to the shell bottom 41. For example, it can also be welded to a cover body covering the end of the shell 40 or welded to a pole.

[0042] In some embodiments, the collecting plate 20 is entirely made of aluminum, but is not limited thereto.

[0043] In some embodiments, the material of the insulating spacer 30 may be PP or PET, but is not limited thereto.

[0044] In some embodiments, the gap H between the welding plate portion 22 and the current collecting plate body 21 is equal to the thickness of the insulating gasket 30 , so that after the insulating gasket 30 is assembled, it can fit and support the welding plate portion 22 .

[0045] In some embodiments, the fuse portion 23 is connected to the outer edge of the welding plate portion 22, and a spacing groove 23 is formed between the outer edge of the welding plate portion 22 and the current collecting plate body 21, and both ends of the spacing groove 23 terminate at the fuse portion 23. Specifically, the length of the fuse portion 23 is much smaller than the length of the spacing groove 23. When the welding plate portion 22 is circular, the angle a defined by the fuse portion 23 can be set to be less than 60 degrees, and correspondingly, the angle defined by the spacing groove 23 is greater than 300 degrees.

[0046] It should be noted that the fuse portion 23 located at the outer edge of the welding plate portion 22 may include at least two sub-fuse portions, and at this time, the two ends of the fuse portion 23 refer to the outer sides of the two outermost sub-fuse portions 23 .

[0047] Specifically, the welding plate portion 22 and the fuse portion 23 are formed by stamping and cutting the current collecting plate 20. The welding plate portion 22, the fuse portion 23 and the current collecting plate body 21 are a single-piece structure, that is, they are formed by processing a single sheet of material. The current collecting plate 20 can be cut before stamping, and then stamped upward to directly form the welding plate portion 22, the fuse portion 23 and the spacing groove 23. Of course, it is not excluded to stamp first and then cut out the fuse portion 23 and the spacing groove 23.

[0048] In addition, the fuse part 23 and the welding plate part 22 are not limited to being formed by punching or cutting. For example, the fuse part 23 can also be welded on the current collecting plate body 21.

[0049] In some embodiments, the welding plate portion 22 is circular, but is not limited thereto.

[0050] Specifically, the first through groove 31 is circular with one end open, and is connected to the second through groove 32 through the open end, and the radius of the first through groove 31 is greater than the radius of the welding plate portion 22. Since the radius of the first through groove 31 is greater than the radius of the welding plate portion 22, when the insulating gasket 30 is assembled, the welding plate portion 22 can smoothly pass through the first through groove 31 upward. Of course, the first through groove 31 is not limited to a circle.

[0051] Specifically, the distance between two opposite side walls of the second through slot 32 , that is, the width of the second through slot 32 is smaller than the diameter of the welding plate portion 22 as a whole, so that the welding plate portion 22 can be supported by the insulating gasket 30 portions on both sides of the second through slot 32 .

[0052] In some embodiments, the two opposite side walls of the second through slot 32 gradually approach each other in a direction away from the first through slot 31. Of course, this is not limited to this, as long as the two sides of the welding plate portion 22 can be supported on the two sides of the insulating gasket 30 on the second through slot 32 when the insulating gasket 30 is assembled in place, and the two ends of the fuse portion 23 are stopped by the two opposite side walls of the second through slot 32.

[0053] In some embodiments, the welding plate portion 22 is disposed corresponding to the middle portion of the winding core 10 , but is not limited thereto.

[0054] Specifically, the winding core 10 has a winding core central hole 11 , and the middle portion of the welding plate portion 22 corresponds to the winding core central hole 11 .

[0055] More specifically, a liquid injection through hole 221 corresponding to the central hole of the winding core 10 is formed in the middle of the welding plate portion 22 , and the liquid injection through hole 221 faces the second through groove 32 .

[0056] In some embodiments, a liquid injection through hole 221 is formed in the middle of the welding plate portion 22 , and the liquid injection through hole 221 faces the second through groove 32 .

[0057] In some embodiments, the power battery structure is a cylindrical power battery structure; the power battery structure further includes a shell 40, the winding core 10, the current collecting disk 20 and the insulating gasket 30 are sleeved in the shell 40; the outer edge of the insulating gasket 30 is adapted to the side wall of the shell 40 to be radially limited. After the insulating gasket 30 is sleeved in the shell 40, the side wall of the shell 40 will radially limit the insulating gasket 30, and at the same time, the fuse part 23 is stopped and limited at the two opposite side walls of the second through groove 32. By the limiting effect of the fuse part 23, the circumferential limit of the insulating gasket 30 can be achieved, and then the reliable assembly of the insulating gasket 30 can be achieved.

[0058] Specifically, the insulating gasket 30 is in a disc shape, and its overall annular outer edge is adapted to the side wall of the shell 40, which can better isolate the collecting plate body 21 and the shell bottom 41. Of course, the insulating gasket 30 is not limited to a disc shape.

[0059] In some embodiments, a sinking area 211 is formed on the collector plate body 21 and is welded to the full tab of the winding core 10 through the sinking area 211. Specifically, the collector plate body 21 is disc-shaped as a whole, and includes at least two sinking areas 211 distributed along the circumference of the collector plate body 21.

[0060] In some embodiments, the current collecting disc body 21 and the insulating gasket 30 are both in the shape of a disc, and the diameter of the insulating gasket 30 may be equal to or slightly larger than the diameter of the current collecting disc body 21 .

[0061] In order to better understand the present application, the assembly process of the power battery structure is described below in conjunction with the specific examples in the accompanying drawings, but this should not be used to limit the present application.

[0062] First, the entire tab at one end of the winding core 10 is flattened.

[0063] Next, the collecting plate body 21 is attached to the full-pole lugs of the winding core 10, and the injection through hole 221 on the welding plate portion 22 is aligned with the central hole 11 of the winding core, and then the collecting plate body 21 is welded to the full-pole lugs of the winding core 10 by laser welding.

[0064] Next, the first through-slot 31 of the insulating gasket 30 is aligned with the welding plate portion 22 , and then the insulating gasket 30 is placed on the current collecting plate body 21 , with the welding plate portion 22 passing through the first through-slot 31 upwards.

[0065] Next, slide the insulating gasket 30 to make the welding plate portion 22 slide relatively to the upper side of the second through groove 32 and the fuse portion 23 slide to the second through groove 32 until the two ends of the fuse portion 23 are stopped by the two opposite side walls of the second through groove 32. At this time, the welding plate portion 22 is supported on the insulating gasket 30, and the insulating gasket 30 is installed in place, and the outer edge of the insulating gasket 30 is basically aligned with the outer wall of the winding core 10.

[0066] Next, the winding core 10, the current collecting plate 20 and the insulating gasket 30 are inserted into the shell 40, and the side wall of the shell 40 radially limits the insulating gasket 30, and the welding plate portion 22 is attached to the inner side of the shell bottom 41. Since the side wall of the shell 40 radially limits the insulating gasket 30, and the fuse portion 23 is stopped and limited by the two opposite side walls of the second through groove 32, the circumferential limit of the insulating gasket 30 can be achieved by the limiting effect of the fuse portion 23. Since the insulating gasket 30 supports the welding plate portion 22, the reliable fit between the welding plate portion 22 and the shell bottom 41 can be ensured.

[0067] Next, the welding plate portion 22 and the case bottom 41 are welded together by laser penetration welding.

[0068] The present application also discloses an assembly method of the aforementioned power battery structure, comprising the following steps:

[0069] The collector plate body 21 is welded to the full pole ear of the winding core 10;

[0070] Align the first through slot 31 of the insulating gasket 30 with the welding plate portion 22 , and then place the insulating gasket 30 on the current collecting plate body 21 , with the welding plate portion 22 passing upward through the first through slot 31 ;

[0071] Slide the insulating gasket 30 to make the welding plate portion 22 slide relatively to the upper side of the second through slot 32 and the fuse portion 23 slide to the second through slot 32 until the two ends of the fuse portion 23 are stopped by the two opposite side walls of the second through slot 32, and the two sides of the welding plate portion 22 are supported on the insulating gasket 30 on both sides of the second through slot 32.

[0072] By means of the above-mentioned assembly method, the insulating gasket 30 separating the current collecting plate body 21 and the welding plate portion 22 can be smoothly assembled on the current collecting plate body 21 to support and limit the welding plate portion 22, and it is also beneficial to ensure the structural strength of the insulating gasket 30, thereby ensuring the functional effect of the insulating gasket 30.

[0073] Based on a specific example, after the insulating gasket 30 is assembled, the above assembly method further includes:

[0074] The winding core 10 , the current collecting plate 20 and the insulating gasket 30 are inserted into the housing 40 , and the side wall of the housing 40 limits the insulating gasket 30 in radial direction.

[0075] Since the side wall of the shell 40 radially limits the insulating gasket 30 and the fuse part 23 is stopped and limited by two opposite side walls of the second through slot 32 , the insulating gasket 30 can be circumferentially limited by the limiting effect of the fuse part 23 .

[0076] 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 power battery structure, characterized in that: include: Roll core; A current collecting disc, the current collecting disc comprising a current collecting disc body and a welding plate portion protruding from the upper side of the current collecting disc body, the current collecting disc body being welded to the full-pole lug at one end of the winding core, and a position of the welding plate portion being connected to the current collecting disc body through a fuse; An insulating gasket, wherein a first through groove and a second through groove are formed on the insulating gasket, the first through groove and the second through groove are connected, and when the insulating gasket is assembled to the collecting plate body, the welding plate portion passes upward through the first through groove and then slides relatively to the upper side of the second through groove, and both sides of the welding plate portion are supported by the insulating gasket on both sides of the second through groove, and both ends of the fuse portion are stopped by two opposite side walls of the second through groove.

2. The power battery structure according to claim 1, characterized in that: The fuse part is connected to the outer edge of the welding plate part, a spacing groove is formed between the outer edge of the welding plate part and the current collecting plate body, and both ends of the spacing groove terminate at the fuse part.

3. The power battery structure according to claim 2, characterized in that: The welding plate portion and the fuse portion are formed by punching and cutting the current collecting plate.

4. The power battery structure according to claim 1, characterized in that: The welding plate portion is circular, the first through groove is circular with one end open to connect with the second through groove, and the radius of the first through groove is greater than the radius of the welding plate portion.

5. The power battery structure according to claim 1 or 4, characterized in that: Two opposite side walls of the second through slot gradually approach each other in a direction away from the first through slot.

6. The power battery structure according to claim 1, characterized in that: The welding plate portion is arranged corresponding to the middle portion of the winding core.

7. The power battery structure according to claim 1, characterized in that: A liquid injection through hole is formed on the welding plate portion, and the liquid injection through hole faces the second through groove.

8. The power battery structure according to claim 1, characterized in that: The power battery structure is a cylindrical power battery structure; the power battery structure also includes a shell, and the winding core, the collecting disk and the insulating gasket are sleeved in the shell; the outer edge of the insulating gasket is adapted to the side wall of the shell to be radially limited.

9. The method for assembling a power battery structure according to claim 1, characterized in that: The steps include: Welding the collector plate body onto the full pole lug of the winding core; Align the first through slot of the insulating gasket with the welding plate portion, and then place the insulating gasket on the current collecting plate body, with the welding plate portion passing upward through the first through slot; Slide the insulating gasket to make the welding plate part slide relatively to the upper side of the second through groove and the fuse part slide to the second through groove until the two ends of the fuse part are stopped by the two opposite side walls of the second through groove, and the two sides of the welding plate part are supported by the insulating gasket on both sides of the second through groove.

10. The method for assembling a power battery structure according to claim 8, characterized in that: The steps include: Welding the collector plate body onto the full pole lug of the winding core; Align the first through slot of the insulating gasket with the welding plate portion, and then place the insulating gasket on the current collecting plate body, with the welding plate portion passing upward through the first through slot; Sliding the insulating gasket, so that the welding plate portion slides relatively to the upper side of the second through slot and the fuse portion slides to the second through slot, until both ends of the fuse portion are stopped by two opposite side walls of the second through slot, and both sides of the welding plate portion are supported by the insulating gasket on both sides of the second through slot; The winding core, the current collecting disk and the insulating gasket are inserted into the shell, and the side wall of the shell limits the insulating gasket in radial direction.

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