Battery cell, battery pack, vehicle and battery cell processing method

Abstract

The invention provides a battery cell, a battery pack, a vehicle and a battery cell processing method. The battery cell comprises a shell, a first connecting part, a first current collecting component and a cover plate assembly, the shell is provided with an opening in the first direction. The first connecting part is located in the shell, and the first connecting part is connected with the shell at the opening; the first current collecting component is arranged in the shell and is connected with the first connecting part; the cover plate assembly is connected with the first connecting part at the opening. According to the battery cell, the battery pack, the vehicle and the battery cell processing method provided by the invention, the qualified rate of finished battery cell products can be ensured.

Description

Technical Field

[0001] The present application relates to the technical field of vehicle batteries, and in particular to a battery cell, a battery pack, a vehicle and a battery cell processing method. Background Art

[0002] The battery cell is an important component of the battery pack and is used to store electrical energy. The battery cell mainly includes a shell, a winding core, two current collecting plates and a cover plate. The cover plate is connected to the shell to form a closed chamber. The winding core and the two current collecting plates are both arranged inside the chamber. The two current collecting plates are insulated, one of which is connected to the winding core and the shell, and the other is connected to the winding core and the cover plate.

[0003] The collector plate and the cover plate are usually fixed by welding when connected to the shell. During the welding process, the shell is easily welded through, which affects the qualified rate of the finished battery cells. Summary of the invention

[0004] The present application provides a battery cell, a battery pack, a vehicle and a battery cell processing method, which can ensure the qualified rate of the battery cell finished products.

[0005] The present application provides a battery cell, wherein the battery cell comprises:

[0006] A housing having an opening along a first direction;

[0007] A first connection portion is located inside the shell, and the first connection portion is connected to the shell at the opening;

[0008] A first current collecting member, disposed inside the housing and connected to the first connecting portion;

[0009] A cover plate assembly is connected to the first connecting portion at the opening.

[0010] The battery cell as described above, wherein the first connecting portion extends along the first direction and is coaxially spaced apart from the shell, a connecting groove is formed between the first connecting portion and the shell, the first current collecting member is connected to the first connecting portion in the connecting groove on a side of the shell facing the shell, and the cover plate assembly is connected to a side of the first connecting portion facing away from the shell.

[0011] The battery cell as described above, wherein the first current collecting member comprises:

[0012] First set of streaming discs;

[0013] The second connection portion is formed by extending the outer peripheral edge of the first collecting plate along the first direction, and the second connection portion is inserted into the connection groove and connected to the side of the first connection portion facing the shell.

[0014] The battery cell as described above, wherein the cover plate assembly comprises:

[0015] Cover, including:

[0016] Cover piece;

[0017] The third connection part is formed by extending the periphery of the cover sheet along the first direction. The third connection part is inserted into the interior of the shell and connected to the side of the first connection part away from the shell. The end surfaces of the cover sheet and the shell at the opening are flush.

[0018] In the battery cell as described above, a guide section is formed on a side of the third connection portion away from the cover sheet, and the guide section gradually inclines toward a direction close to a central axis of the cover sheet along a direction away from the cover sheet.

[0019] In the battery cell as described above, a concave portion is formed on the periphery of the cover toward the interior of the shell, and the concave portion cooperates with the third connecting portion to form an annular groove.

[0020] The battery cell as described above, wherein the battery cell further comprises a second current collecting member, and the second current collecting member comprises:

[0021] a second current collecting plate, wherein a through hole is opened in the center of the first current collecting plate along the first direction, the second current collecting plate is installed at the through hole of the first current collecting plate, and the first current collecting plate and the second current collecting plate are spaced apart;

[0022] A guide post is connected to the second current collecting plate, and the guide post is connected to the cover plate assembly.

[0023] The battery cell as described above, wherein the battery cell further includes a winding core, the winding core is arranged inside the shell, and a first pole ear and a second pole ear are formed on the side of the winding core facing the opening, the first current collecting disk is connected to the first pole ear, and the second current collecting disk is connected to the second pole ear.

[0024] The battery cell as described above, wherein the battery cell further comprises a sealing mandrel, and the sealing mandrel comprises:

[0025] The shaft rod is a tubular structure with a hollow interior and two through ends, and a plurality of through holes are formed on the shaft rod along its radial direction;

[0026] A sealing head connected to one end of the shaft;

[0027] The shaft rod passes through the cover plate assembly, the second current collecting member extends into the interior of the winding core, and the sealing head is sealed and fixedly connected to a side of the cover plate assembly away from the shell; or

[0028] The shaft rod penetrates a side wall portion of the shell body that is arranged opposite to the opening and extends into the interior of the winding core, and the sealing head is sealed and fixedly connected to a side wall portion of the shell body that is arranged opposite to the opening.

[0029] The present application also provides a battery pack, wherein the battery pack includes a plurality of battery cells as described above.

[0030] The present application also provides a vehicle, wherein the vehicle includes the battery pack as described above.

[0031] The present application also provides a battery core processing method, wherein the battery core processing method is used to process the battery core as described above, and the battery core processing method comprises:

[0032] Disposing a housing so that the housing has an opening along a first direction;

[0033] A first current collecting component is arranged inside the housing;

[0034] Bend a portion of the shell toward the inside of the shell at the opening to form a first connecting portion;

[0035] connecting the first current collecting member to the first connecting portion;

[0036] A cover plate assembly is arranged at the opening, and the cover plate assembly is connected to the first connecting portion.

[0037] The battery cell processing method as described above, wherein a portion of the shell is bent toward the inside of the shell at the opening to form a first connecting portion, comprises:

[0038] The first connection portion is extended along the first direction and spaced apart from the shell, so that a connection groove is formed between the first connection portion and the shell.

[0039] The battery cell processing method as described above, wherein a first current collecting member is arranged inside the housing, comprises:

[0040] Processing the first current collecting member so that the first current collecting member includes a first current collecting plate and a second connecting portion connected to each other, and the second connecting portion extends along the first direction;

[0041] Connecting the first current collecting member to the first connecting portion includes:

[0042] The second connection portion is connected to a side of the first connection portion facing the housing in the connection slot.

[0043] The battery cell processing method as described above, wherein a cover plate assembly is provided at the opening, and the cover plate assembly is connected to the first connecting portion, comprising:

[0044] Processing the cover plate assembly so that the cover plate assembly includes a cover plate, the cover plate includes a cover sheet and a third connecting portion connected to each other, and the third connecting portion extends along the first direction;

[0045] The third connection portion is inserted into the shell body so as to be connected with the side of the shell body which is away from the first connection portion, and the cover sheet is flush with the end surface of the shell body at the opening.

[0046] The battery cell, battery pack, vehicle and battery cell processing method provided by the present application, by setting a first connecting portion on the inner side of the shell opening, and connecting the first current collecting component and the cover plate assembly to the first connecting portion respectively, the first current collecting component and the cover plate assembly are indirectly connected to the shell respectively through the first connecting portion, effectively avoiding the situation where the first current collecting component and the cover plate assembly are directly connected to the shell and cause damage to the shell, thereby ensuring the qualified rate of the finished battery cells. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 A schematic diagram of the three-dimensional structure of a battery cell provided in an embodiment of the present application;

[0048] Figure 2 An exploded diagram of a battery cell provided in an embodiment of the present application;

[0049] Figure 3 A front view of a shell of a battery cell provided in an embodiment of the present application;

[0050] Figure 4 For along Figure 3 Schematic diagram of the cross-section structure along the AA line;

[0051] Figure 5 A front view of a battery cell provided in an embodiment of the present application;

[0052] Figure 6 For along Figure 5 Schematic diagram of the cross-sectional structure of the CC line;

[0053] Figure 7 for Figure 6 A magnified schematic diagram of the structure at D in the middle;

[0054] Figure 8 A schematic diagram of the three-dimensional structure of a first current collecting component of a battery cell provided in an embodiment of the present application;

[0055] Fig. 9 A front view of a first current collecting component of a battery cell provided in an embodiment of the present application;

[0056] Fig.10 For along Fig. 9 Schematic diagram of the cross-sectional structure of the EE line;

[0057] Fig.11 A schematic diagram of the three-dimensional structure of a cover plate assembly of a battery cell provided in an embodiment of the present application;

[0058] Fig.12 An exploded view of a cover plate assembly of a battery cell provided in an embodiment of the present application;

[0059] Fig.13 A top view of a cover plate assembly of a battery cell provided in an embodiment of the present application;

[0060] Fig.14 For along Fig.11 Schematic diagram of the cross-sectional structure of the FF line;

[0061] Fig.15 for Fig.14 The enlarged structural diagram at G in the middle;

[0062] Fig.16 Another embodiment of the present application is Fig.14 The enlarged structural diagram at G in the middle;

[0063] Fig.17 Another embodiment of the present application is Fig.14 The enlarged structural diagram at G in the middle;

[0064] Fig.18 A schematic diagram of the three-dimensional structure of the second current collecting component of the battery cell provided in an embodiment of the present application;

[0065] Fig.19 A top view of a second current collecting member of a battery cell provided in an embodiment of the present application;

[0066] Fig. 20 For along Fig.19 Schematic diagram of the cross-sectional structure of the middle HH line;

[0067] Fig.21 A schematic diagram of the three-dimensional structure of a winding core of a battery cell provided in an embodiment of the present application;

[0068] Fig. 22 A front view of a winding core of a battery cell provided in an embodiment of the present application;

[0069] Fig.23 For along Fig. 22 Schematic diagram of the cross-sectional structure of the middle II line;

[0070] Fig.24 for Fig.23 Schematic diagram of the enlarged structure at J in the middle;

[0071] Fig.25 A schematic diagram of the three-dimensional structure of an insulating member of a battery cell provided in an embodiment of the present application;

[0072] Fig.26A schematic diagram of the three-dimensional structure of the insulating member of the battery cell provided in an embodiment of the present application from another angle;

[0073] Fig. 27 A bottom view of an insulating member of a battery cell provided in an embodiment of the present application;

[0074] Fig.28 For along Fig. 27 Schematic diagram of the cross-sectional structure of the KK line;

[0075] Fig.29 A schematic diagram of the three-dimensional structure of a sealing mandrel of a battery cell provided in an embodiment of the present application;

[0076] Fig.30 A front view of a sealing mandrel of a battery cell provided in an embodiment of the present application;

[0077] Fig.31 For along Fig.30 Schematic diagram of the cross-sectional structure along the L-L line;

[0078] Fig.32 A schematic diagram of the three-dimensional structure of a sealing mandrel of a battery cell provided in another embodiment of the present application;

[0079] Fig.33 Another embodiment of the present application provides a battery cell Figure 5 Schematic diagram of the cross-sectional structure of the CC line;

[0080] Fig.34 for Fig.33 Schematic diagram of the enlarged structure at M in the middle;

[0081] Fig.35 A battery cell provided in another embodiment of the present application Figure 5 Schematic diagram of the cross-sectional structure of the CC line;

[0082] Fig.36 for Fig.35 Schematic diagram of the enlarged structure at N in the middle;

[0083] Fig.37 for Figure 4 A schematic diagram of the enlarged structure at B in the middle;

[0084] Fig.38 A flow chart of a battery cell processing method provided in an embodiment of the present application.

[0085] Description of Figure Numbers:

[0086] 1. Shell; 11. First connection part; 12. Connection groove; 13. Thinning annular groove; 2. First current collecting member; 21. First current collecting plate; 22. Second connection part; 3. Cover plate assembly; 31. Cover plate; 311. Cover sheet; 312. Third connection part; 3121. Guide section; 3122. Annular groove; 32. Pole; 321. First extension part; 322. Second extension part; 323. Annular abutment part; 324. Countersunk hole; 33. Sealing ring; 331 , first sealing lip; 332, second sealing lip; 4, second current collecting component; 41, second current collecting plate; 42, guide column; 421, through hole; 5, winding core; 51, first pole ear; 511, first rib; 52, second pole ear; 521, second rib; 53, inner hole; 54, hollow part; 6, sealing core shaft; 61, shaft; 611, through hole; 62, sealing head; 7, insulating member; 71, limiting convex ring; 72, convex rib; 73, liquid passage groove; 8, sealing plug;

[0087] X, first direction. DETAILED DESCRIPTION

[0088] In order to more clearly understand the above-mentioned objectives, features and advantages of the present disclosure, the scheme of the present disclosure will be further described below. It should be noted that the embodiments of the present disclosure and the features in the embodiments can be combined with each other without conflict.

[0089] In the following description, many specific details are set forth to facilitate a full understanding of the present disclosure, but the present disclosure may also be implemented in other ways different from those described herein; it is obvious that the embodiments in the specification are only part of the embodiments of the present disclosure, rather than all of the embodiments.

[0090] It should be noted that, in this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the term "comprises" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0091] With the rapid development of electric vehicles, the endurance and charging efficiency of electric vehicles have become the areas of concern for consumers. With the improvement of battery pack energy density and fast charging capability, the current battery cells have the following problems:

[0092] The shell is getting thinner and thinner. In order to prevent damage during welding of the shell, the welding matching accuracy requirements at the shell opening are getting higher and higher, and the sealing strength of the shell opening is getting worse, resulting in safety risks to the battery cells.

[0093] The welding of the negative electrode collector plate and the shell opening requires a high degree of matching accuracy, which makes the processing of the negative electrode collector plate more difficult and affects the stability of the overall process of the battery cell.

[0094] When the negative electrode collector plate is welded to the shell, since both the shell and the negative electrode collector plate are relatively thin, the welding area between the negative electrode collector plate and the shell needs to be increased when designing a high-rate battery cell, further increasing the problem of shell welding damage.

[0095] For cylindrical battery cells, as the battery cells become larger, the central hole diameter of the internal core becomes larger. The expansion of the core at the end of the cycle can easily lead to collapse of the inner hole, causing lithium deposition in the core and thermal runaway of the battery cell.

[0096] The radial dimension of the core is large, which can easily lead to temperature accumulation inside the core during high-rate charging and discharging, causing excessive temperature difference between the inside and outside of the core, thus affecting the cycle life of the core.

[0097] In view of the problems existing in the above-mentioned related technologies, the embodiments of the present application provide a battery cell, a battery pack, a vehicle and a battery cell processing method, so as to optimize the assembly structure of the shell opening, reduce the matching accuracy requirements between the cover assembly and the shell, improve the structural strength of the shell opening and reduce the damage to the shell during welding; optimize the assembly scheme of the first current collecting component and the shell, reduce the difficulty of assembly, further improve the structural strength of the shell opening and reduce the damage to the shell during welding; reduce the risk of collapse of the inner hole of the high-rate battery cell, and at the same time increase the path for the heat inside the core to be conducted to the outside, thereby reducing the temperature inside the core and improving the cycle life of the core.

[0098] It should be noted that the term “first direction X” indicating a direction in the following description is only used to more clearly illustrate the specific structure of the present application in conjunction with the accompanying drawings, and the present application is not limited thereto.

[0099] The battery cell may be a square battery cell or a cylindrical battery cell. For example, the cylindrical battery cell is taken as an example for detailed description in the embodiments and drawings of the present application.

[0100] like Figures 1 to 7 As shown, the present application provides a battery cell, wherein the battery cell includes a shell 1, a first connecting portion 11, a first current collecting member 2 and a cover plate assembly 3.

[0101] The shell 1 has an opening along the first direction X. Specifically, the shell 1 is in the shape of a hollow cylinder. The first direction X is the axial direction of the shell 1. Along its axial direction, the shell 1 has a first end and a second end. The first end is open to form an opening, and the second end is closed. When the shell 1 is processed to form a battery cell and then assembled for use, the first end is roughly the upper end and the second end is roughly the lower end.

[0102] The first connection part 11 is located inside the shell 1, and the first connection part 11 is connected to the shell 1 at the opening; the shell 1 and the first connection part 11 are integrally formed to ensure the connection strength between the two; optionally, the first connection part 11 is formed by bending and extending from the opening toward the inside of the shell 1. By setting the first connection part 11, the structural strength of the opening of the shell 1 can be effectively improved.

[0103] The first current collecting component 2 is arranged inside the housing 1 and connected to the first connecting portion 11; the cover plate assembly 3 is connected to the first connecting portion 11 at the opening and closes the opening of the housing 1. The first current collecting component 2 and the cover plate assembly 3 are connected to the housing 1 indirectly through the first connecting portion 11, which effectively avoids the situation where the first current collecting component 2 and the cover plate assembly 3 are directly connected to the housing 1 and cause damage to the housing 1, thereby ensuring the qualified rate of the finished battery cells.

[0104] like Figure 4 , Figure 6 and Figure 7 As shown, the battery cell provided by the embodiment of the present application, wherein the first connection portion 11 extends along the first direction X and is coaxially spaced with the shell 1, an annular connection groove 12 is formed between the first connection portion 11 and the shell 1, the first current collecting member 2 is connected to the side of the first connection portion 11 facing the shell 1 in the connection groove 12, and the cover plate assembly 3 is connected to the side of the first connection portion 11 away from the shell 1. In this way, both radial side surfaces of the first connection portion 11 are used for connection, while ensuring the connection area between the first connection portion 11 and the first current collecting member 2 and between the first connection portion 11 and the cover plate assembly 3, the space occupied by the first current collecting member 2 and the cover plate assembly 3 along the first direction X when the connection with the shell 1 is realized is reduced, the compactness of the overall structure of the battery cell is improved, and thus the energy density of the battery cell is improved.

[0105] like Figures 8 to 10As shown, the battery cell provided by the embodiment of the present application, wherein the first current collecting component 2 includes an integrally formed first current collecting disk 21 and a second connecting portion 22; the second connecting portion 22 is formed by extending the outer peripheral edge of the first current collecting disk 21 along the first direction X, and the second connecting portion 22 is substantially perpendicular to the first current collecting disk 21, which can effectively improve the structural strength of the first current collecting component 2; the second connecting portion 22 is inserted into the connecting groove 12 and connected to the side of the first connecting portion 11 facing the shell 1, and the first connecting portion 11 and the second connecting portion 22 have the same extension direction, which is beneficial to improving the fit between the first connecting portion 11 and the second connecting portion 22 during assembly to ensure the reliability of the connection between the two.

[0106] By adopting the second connection portion 22 to connect with the first connection portion 11 to achieve the connection between the first current collecting member 2 and the housing 1 , the matching accuracy requirement between the housing 1 and the first current collecting member 2 can be effectively reduced.

[0107] like Figures 11 to 15 As shown, the battery cell provided by the embodiment of the present application, wherein the cover plate assembly 3 includes a cover plate 31, the cover plate 31 includes an integrally formed cover sheet 311 and a third connection portion 312; the third connection portion 312 is formed by extending the periphery of the cover sheet 311 along the first direction X, and the third connection portion 312 is substantially perpendicular to the cover sheet 311, which can effectively improve the structural strength of the cover plate 31; the third connection portion 312 is inserted into the interior of the shell 1 and connected to the side of the first connection portion 11 away from the shell 1, and the third connection portion 312 has the same extension direction as the first connection portion 11, which is beneficial to improving the degree of fit between the first connection portion 11 and the third connection portion 312 during assembly to ensure the reliability of the connection between the two, and the cover sheet 311 is flush with the end face of the shell 1 at the opening and closes the opening of the shell 1 to ensure the flatness of the end of the battery cell along the first direction X.

[0108] By adopting the third connection portion 312 to connect with the first connection portion 11 to achieve the connection between the cover assembly 3 and the shell 1, the matching accuracy requirement between the shell 1 and the cover assembly 3 can be effectively reduced.

[0109] like Fig.16 As shown, in the battery cell provided by the embodiment of the present application, a guide section 3121 is formed on the side of the third connection portion 312 away from the cover plate 31, and the guide section 3121 gradually tilts toward the direction close to the central axis of the cover plate 311 along the direction away from the cover plate 311. That is, along the direction away from the cover plate 311, the guide section 3121 is a cone-shaped structure with a gradually decreasing diameter, so that when the cover plate 31 is inserted into the interior of the housing 1, the insertion direction of the cover plate 31 is guided and straightened, which is conducive to improving the assembly qualification rate between the cover plate 31 and the housing 1, avoiding jamming during the assembly process of the cover plate 31 and the housing 1, and realizing the rapid assembly of the cover plate 31 and the housing 1.

[0110] like Fig.17 As shown, in the battery cell provided by the embodiment of the present application, the periphery of the cover plate 311 is recessed toward the interior of the shell 1 to form a recess, and the recess cooperates with the third connecting portion 312 to form an annular groove 3122. This can further enhance the structural strength of the periphery of the cover plate 31 to ensure that the third connecting portion 312 is reliably connected to the first connecting portion 11, improve the matching accuracy between the cover plate 31 and the first connecting portion 11, and enhance the assembly qualification rate between the cover plate 31 and the shell 1.

[0111] like Figures 11 to 14 As shown, in the battery cell provided in the embodiment of the present application, the cover plate assembly 3 further includes a pole 32 and a sealing ring 33 .

[0112] A through hole is opened in the center of the cover plate 311 along the first direction X, and the pole 32 is installed at the through hole of the cover plate 311 ; the sealing ring 33 is arranged between the pole 32 and the cover plate 311 , and the pole 32 and the cover plate 311 are sealed together through the sealing ring 33 .

[0113] The periphery of the sealing ring 33 is formed with a first sealing lip 331 and a second sealing lip 332. The first sealing lip 331 and the second sealing lip 332 are spaced apart along the first direction X to form a sealing ring groove. The sealing ring 33 is arranged at the through hole in the center of the cover plate 311, and the inner edge of the cover plate 311 is embedded in the sealing ring groove and is sealed and positioned with the sealing ring 33.

[0114] A first extension portion 321 and a second extension portion 322 are formed on the periphery of the pole 32. The first extension portion 321 and the second extension portion 322 are spaced apart along the first direction X to form a positioning ring groove. The sealing ring 33 is embedded in the positioning ring groove. The first sealing lip 331 is pressed between the first extension portion 321 and the cover plate 311, and the second sealing lip 332 is pressed between the second extension portion 322 and the cover plate 311 to ensure that the pole 32, the sealing ring 33 and the cover plate 31 are sealed and positioned.

[0115] like Figures 11 to 14 As shown, in the battery cell provided by the embodiment of the present application, a countersunk hole 324 for liquid injection is provided in the center of the pole 32, a step surface facing the outside of the shell 1 is formed inside the countersunk hole 324, and an annular abutment portion 323 is protruded on the side of the pole 32 facing the inside of the shell 1.

[0116] like Figures 18 to 20 As shown, the battery cell provided by the embodiment of the present application further comprises a second current collecting member 4, wherein the second current collecting member 4 comprises a second current collecting disc 41 and a guide post 42. A through hole is provided in the center of the first current collecting disc 21 along the first direction X, and the second current collecting disc 41 is installed at the through hole of the first current collecting disc 21, and the first current collecting disc 21 and the second current collecting disc 41 are concentric and spaced apart;

[0117] The guide post 42 is connected to the second current collecting plate 41 , and the guide post 42 is connected to the cover plate assembly 3 .

[0118] Optionally, along the first direction X, the guide post 42 has a first end and a second end, the first end of the guide post 42 is welded and fixed to the second current collecting disk 41, and the second end of the guide post 42 is used to position and abut with the annular abutment portion 323 of the pole 32; specifically, a through hole is opened in the center of the second current collecting disk 41, and the first end of the guide post 42 is formed with a step surface facing the second current collecting disk 41 by reducing the diameter, and a part of the first end of the guide post 42 is embedded in the through hole of the second current collecting disk 41, and the step surface of the first end of the guide post 42 abuts against the second current collecting disk 41 to achieve positioning and assembly accuracy between the two; the first end of the guide post 42 is welded and fixed to the second current collecting disk 41 to ensure the reliability of the connection between the two; the second end of the guide post 42 is also reduced to form a step surface, a part of the second end of the guide post 42 is embedded in the countersunk hole 324 of the pole 32, and the step surface of the second end of the guide post 42 abuts against the annular abutment portion 323 of the pole 32 to ensure positioning and assembly accuracy between the two.

[0119] Optionally, along the direction from the first end of the guide column 42 to the second end of the guide column 42, the step surface of the second end of the guide column 42 is a conical surface with a gradually decreasing diameter, and the annular abutment portion 323 has a matching conical abutment surface to guide the assembly of the two, reduce the tolerance generated along the radial direction of the shell 1 after the two are assembled, and further improve the assembly accuracy of the two.

[0120] The guide post 42 is provided with a through hole 421 penetrating along the first direction X. The through hole 421 on the guide post 42 corresponds coaxially to and is in communication with the countersunk hole 324 on the pole 32 .

[0121] like Figure 21 to Figure 24 As shown, the battery cell provided in the embodiment of the present application, wherein the battery cell also includes a winding core 5, the winding core 5 is arranged inside the shell 1, and a first pole ear 51 and a second pole ear 52 are formed on the side of the winding core 5 facing the opening, the first current collecting disk 21 is abutted against the first pole ear 51 and welded and fixed, and the second current collecting disk 41 is abutted against the second pole ear 52 and welded and fixed.

[0122] Optionally, the first pole lug 51 is a negative pole lug, the first current collecting disk 21 is a negative current collecting disk, the second pole lug 52 is a positive pole lug, and the second current collecting disk 41 is a positive current collecting disk. The first pole lug 51 is an annular structure adapted to the first current collecting disk 21, the second pole lug 52 is a circular structure adapted to the second current collecting disk 41, and the second pole lug 52 is located on the inner side of the first pole lug 51, and the two are coaxially arranged and spaced from each other.

[0123] Optionally, a plurality of first ribs 511 are protruding from one side of the first current collecting disc 21 facing the first pole lug 51, and the plurality of first ribs 511 are arranged at intervals along the circumference of the shell 1. By arranging the first ribs 511, the tightness of the pressing between the first current collecting disc 21 and the first pole lug 51 can be increased to ensure the pass rate of the subsequent welding of the first current collecting disc 21 and the first pole lug 51.

[0124] Optionally, a plurality of second ribs 521 are protruding from one side of the second current collecting disc 41 facing the second pole lug 52, and the plurality of second ribs 521 are arranged at intervals along the circumference of the shell 1. By arranging the second ribs 521, the tightness of the pressing between the second current collecting disc 41 and the second pole lug 52 can be increased to ensure the pass rate of the subsequent welding of the second current collecting disc 41 and the second pole lug 52.

[0125] Optionally, a plurality of hollow portions 54 penetrating along the first direction X are formed on the first collecting disc 21 and the second collecting disc 41 . The hollow portions 54 are provided to facilitate the electrolyte to flow into the winding core 5 during injection, thereby improving the electrolyte infiltration efficiency.

[0126] The hollow portion 54 may be a hole-shaped structure, or the hollow portion 54 may be a groove-shaped structure located at the inner edge of the first current collecting disk 21 or at the outer edge of the second current collecting disk 41 .

[0127] An inner hole 53 penetrating along the first direction X is formed inside the winding core 5 . The countersunk hole 324 on the pole 32 and the through hole on the guide column 42 are coaxially corresponding to the inner hole 53 inside the winding core 5 and are connected to each other.

[0128] like Figure 25 to Figure 28 As shown, the battery cell provided in the embodiment of the present application, wherein the battery cell also includes an insulating member 7, which is arranged between the first current collecting disk 21 and the cover plate assembly 3 and between the second current collecting disk 41 and the cover plate assembly 3, and a through hole for the pole 32 to pass through is opened in the center of the insulating member 7, and a limiting convex ring 71 is convexly provided on the surface of the insulating member 7 on the side away from the cover plate assembly 3, and the limiting convex ring 71 is embedded between the first current collecting disk 21 and the second current collecting disk 41 to maintain the gap between the first current collecting disk 21 and the second current collecting disk 41 to ensure the insulation setting of the two.

[0129] Optionally, a plurality of ribs 72 are protruding from the surface of one side of the insulating member 7 facing the cover assembly 3, the ribs 72 extend radially along the shell 1, and the plurality of ribs 72 are arranged at intervals along the circumference of the shell 1, the ribs 72 can abut against the second sealing lip 332 to increase the friction between the cover assembly 3 and the insulating member 7, and at the same time cooperate with the limiting convex ring 71 to fix the relative position between the cover assembly 3 and the winding core 5.

[0130] Optionally, the insulating member 7 is provided with a plurality of liquid holes extending along the first direction X, and / or the inner edge and / or outer edge of the insulating member 7 is provided with a plurality of liquid grooves 73 extending along the first direction X, so as to achieve the effect of electrolyte conduction and weight reduction.

[0131] like Figures 29 to 34 As shown, the battery cell provided in the embodiment of the present application further includes a sealing core shaft 6 , and the sealing core shaft 6 includes a shaft rod 61 and a sealing head 62 .

[0132] The shaft rod 61 is a tubular structure with a hollow interior and two through ends. A plurality of through holes 611 are formed in the shaft rod 61 along its radial direction to achieve the effects of reducing weight and allowing electrolyte to flow.

[0133] The sealing head 62 is connected to one end of the shaft 61 and is used for sealing to prevent leakage after the battery cell is assembled.

[0134] Specifically, the shaft rod 61 passes through the cover plate assembly 3 and the second current collecting component 4 and extends into the interior of the winding core 5, that is, the shaft rod 61 sequentially passes through the countersunk hole 324 on the pole 32, the through hole 53 on the guide column 42 and the interior of the winding core 5, and the sealing head 62 is sealed and fixedly connected to the side of the cover plate assembly 3 facing away from the shell 1, that is, the sealing head 62 is embedded in the countersunk hole 324 of the pole 32 and abuts against the step surface of the countersunk hole 324 to seal the countersunk hole 324.

[0135] Alternatively, the shaft rod 61 passes through a side wall portion of the shell 1 opposite to the opening and extends into the interior of the winding core 5, that is, the shaft rod 61 passes through the shell 1 from the bottom of the battery cell and extends into the inner hole 53 of the winding core 5, and the sealing head 62 is sealed and fixedly connected to the wall portion of the shell 1 opposite to the opening. At this time, the countersunk hole 324 on the pole 32 is sealed by the sealing plug 8.

[0136] The shaft 61 can provide support for the core 5 to prevent the inner hole 53 of the core 5 from collapsing, causing lithium deposition in the core 5 and thermal runaway of the battery cell. At the same time, the heat inside the core 5 is transferred to the outside of the shell 1 through the shaft 61 to reduce the temperature inside the core 5, reduce the temperature accumulation inside the core 5, reduce the temperature difference between the inside and outside of the core 5, and ensure the cycle life of the core 5.

[0137] The materials of the shaft 61 and the sealing head 62 can be the same or different. Optionally, the sealing head 62 is made of aluminum alloy, which has the advantages of light weight and high strength; the shaft 61 is made of plastic material to effectively reduce the manufacturing cost and weight of the sealing core shaft 6. The plastic material used for the shaft 61 needs to be a high thermal conductivity material to ensure that the heat inside the winding core 5 can be effectively transferred to the outside through the shaft 61. For example, the plastic material used to manufacture the shaft 61 can be polyimide, polyetheretherketone, polyoxymethylene resin or polytetrafluoroethylene.

[0138] The shaft 61 and the sealing head 62 may be fixedly connected or detachably connected via a structure such as a thread.

[0139] Alternatively, if Figure 35 to Figure 36 As shown, according to the design requirements of products of different chemical systems, for cells with smaller expansion and less heat generation, a design scheme without a sealed core shaft 6 can also be adopted to reduce the overall cost of the cell.

[0140] Alternatively, if Fig.37 As shown, in the battery cell provided by the embodiment of the present application, a thinning annular groove 13 is recessed on the surface of the side wall of the shell 1 facing away from the opening and toward the outside of the shell 1. When the internal pressure of the shell 1 reaches a certain threshold, the thinning annular groove 13 will rupture to achieve pressure relief.

[0141] The present application also provides a battery pack, wherein the battery pack includes a plurality of battery cells as described above.

[0142] The battery pack provided in the present application has a battery cell in which a first connecting portion is arranged on the inner side of the opening of the shell, and the first current collecting component and the cover plate assembly are respectively connected to the first connecting portion, so that the first current collecting component and the cover plate assembly are respectively connected to the shell indirectly through the first connecting portion, effectively avoiding the situation in which the first current collecting component and the cover plate assembly are directly connected to the shell and cause damage to the shell, thereby ensuring the qualified rate of the finished battery cells.

[0143] The present application also provides a vehicle, wherein the vehicle includes the battery pack as described above.

[0144] In the vehicle provided in the present application, the battery pack of the battery cell is provided with a first connecting portion on the inner side of the opening of the shell, and the first current collecting component and the cover plate assembly are respectively connected to the first connecting portion, so that the first current collecting component and the cover plate assembly are indirectly connected to the shell respectively through the first connecting portion, effectively avoiding the situation where the first current collecting component and the cover plate assembly are directly connected to the shell and cause damage to the shell, thereby ensuring the qualified rate of the finished battery cells.

[0145] The embodiment of the present application further provides a battery cell processing method, wherein the battery cell processing method is used to process the battery cell as described above, and the battery cell processing method includes:

[0146] The shell is arranged so that the shell has an opening along a first direction so as to allow other components of the battery core to be placed inside the shell.

[0147] A first current collecting member is disposed inside the housing.

[0148] A portion of the shell is bent toward the inside of the shell at the opening to form a first connection portion, so as to effectively ensure the connection strength between the first connection portion and the shell, and the structural strength of the shell opening can be effectively improved through the first connection portion.

[0149] The first current collecting component is connected to the first connecting portion to achieve fixed connection between the first current collecting component and the shell.

[0150] A cover plate assembly is arranged at the opening, and the cover plate assembly is connected to the first connecting portion to achieve fixed connection between the cover plate assembly and the shell, thereby completing the sealing of the opening.

[0151] The battery cell processing method provided in an embodiment of the present application, wherein a portion of the shell is bent toward the inside of the shell at the opening to form a first connecting portion, specifically comprising:

[0152] The first connection portion is extended along the first direction and spaced apart from the shell, so that a connection groove is formed between the first connection portion and the shell. Thus, the first connection portion has a certain area on the side facing the shell and the side away from the shell, and both can be used for connection.

[0153] The battery cell processing method provided in the embodiment of the present application, wherein a first current collecting component is arranged inside the shell, specifically comprising:

[0154] The first current collecting component is processed so that the first current collecting component includes a first current collecting plate and a second connecting portion connected to each other, and the second connecting portion extends along the first direction. The first connecting portion and the first current collecting plate are substantially vertical, which can effectively improve the structural strength of the first current collecting component.

[0155] The battery cell processing method provided in an embodiment of the present application, wherein the first current collecting member is connected to the first connecting portion, specifically comprises:

[0156] The second connecting portion is connected to a side of the first connecting portion facing the shell in the connecting groove.

[0157] The battery cell processing method provided in the embodiment of the present application, wherein a cover plate assembly is provided at the opening, and the cover plate assembly is connected to the first connecting portion, specifically comprising:

[0158] The cover plate assembly is processed so that the cover plate assembly includes a cover plate, and the cover plate includes a connected cover sheet and a third connecting portion, so that the third connecting portion extends along the first direction; the third connecting portion is roughly perpendicular to the cover sheet, which can effectively improve the structural strength of the cover plate.

[0159] The third connecting part is inserted into the side of the shell that is away from the shell and is connected with the first connecting part. In this way, the connectable area of ​​the first connecting part facing the shell and the connectable area of ​​the first connecting part facing away from the shell are fully utilized. While achieving effective connection between the cover plate assembly and the shell and between the first current collecting member and the shell, the space occupied by the cover plate assembly and the first current collecting member along the first direction when they are assembled is reduced, thereby improving the energy density of the battery cell.

[0160] Make the cover sheet flush with the end surface of the shell at the opening to ensure the flatness of the end surface of the battery cell.

[0161] like Fig.38 As shown, the battery cell processing method provided in the embodiment of the present application includes:

[0162] Winding the winding core and setting the first pole lug and the second pole lug;

[0163] Welding and fixing the first current collecting plate of the first current collecting component to the first electrode tab, and welding and fixing the second current collecting plate of the second current collecting component to the second electrode tab;

[0164] Placing the winding core, the first current collecting component and the second current collecting component into the interior of the housing;

[0165] At the opening of the shell, a portion of the shell is bent toward the inside of the shell to form a first connecting portion;

[0166] Welding and fixing the first connection portion to the second connection portion of the first current collecting member;

[0167] placing an insulating member into the interior of the housing;

[0168] The cover plate assembly is arranged at the opening of the shell, and the third connecting portion and the first connecting portion of the cover plate of the cover plate assembly are welded and fixed;

[0169] Conduct a helium test on the inside of the shell to confirm its sealing performance;

[0170] injecting electrolyte into the interior of the shell;

[0171] Keep the battery cell at high temperature to accelerate the internal reaction of the battery cell, which is conducive to the absorption of the electrolyte;

[0172] The battery cell is subjected to negative pressure formation to discharge the gas generated inside the shell to improve the safety and reliability of the battery cell;

[0173] Aging the battery cell to make the electrolyte infiltration better, which is beneficial to the stability of the battery cell performance. At the same time, it can promote the decomposition of the electrolyte and make the electrochemical performance of the battery cell quickly reach stability;

[0174] Refill the battery cell for the second time to make up for the electrolyte loss in the previous process, so that the battery cell can maintain normal working condition;

[0175] Insert the sealing mandrel and fix the sealing mandrel;

[0176] Conduct a secondary helium test on the battery cell to reconfirm the sealing performance of the finished battery cell;

[0177] Divide the capacity of the battery cells.

[0178] The battery cell processing method provided in the embodiment of the present application adds a step of bending a part of the shell toward the inside of the shell at the opening of the shell to form a first connecting portion, and welding and fixing the first connecting portion to the second connecting portion of the first current collecting disk. By introducing the first connecting portion, the processing accuracy requirement between the first current collecting component and the shell is reduced, the manufacturing cost of the battery cell is reduced, and the assembly reliability of the first current collecting component and the shell is also improved. Finally, the conduction between the shell and the first current collecting component is ensured by welding.

[0179] The battery cell processing method provided in the embodiment of the present application adds a step of bending a part of the shell toward the inside of the shell to form a first connection part at the opening of the shell, setting the cover plate assembly at the opening of the shell, and welding and fixing the third connection part of the cover plate of the cover plate assembly to the first connection part. The arrangement of the first connection part enhances the structural strength of the shell opening, and the accuracy of the shell opening is also ensured by the first connection part. The third connection part of the cover plate improves the fit between the cover plate and the shell, increases the fit surface, and improves the assembly accuracy of the shell and the cover plate after fit. Finally, after being fixed by welding, the connection strength between the cover plate and the shell opening is also improved.

[0180] The battery cell processing method provided in the embodiment of the present application introduces a sealing core shaft structure when sealing the battery cell. The sealing core shaft is inserted into the interior of the winding core from the countersunk hole of the pole to fix the inner hole of the winding core. At the same time, the sealing head of the sealing core shaft cooperates with the cover plate pole and is welded and sealed. The shaft rod can fix and support the inner hole of the winding core, and can also introduce the heat inside the winding core to the pole and take the heat away through the subsequent grouped bars.

[0181] The battery cell processing method provided in the present application provides a first connecting portion on the inner side of the shell opening, and connects the first current collecting component and the cover plate assembly to the first connecting portion respectively, thereby indirectly connecting the first current collecting component and the cover plate assembly to the shell respectively through the first connecting portion, effectively avoiding the situation in which the first current collecting component and the cover plate assembly are directly connected to the shell and cause damage to the shell, thereby ensuring the qualified rate of the finished battery cells.

Claims

1. A battery cell, characterized in that: The battery cell comprises: A housing having an opening along a first direction; A first connection portion is located inside the shell, and the first connection portion is connected to the shell at the opening; A first current collecting member, disposed inside the housing and connected to the first connecting portion; A cover plate assembly is connected to the first connecting portion at the opening.

2. The battery cell according to claim 1, characterized in that: The first connection portion extends along the first direction and is coaxially spaced apart from the shell. A connection groove is formed between the first connection portion and the shell. The first current collecting member is connected to the first connection portion in the connection groove on a side facing the shell. The cover plate assembly is connected to a side of the first connection portion facing away from the shell.

3. The battery cell according to claim 2, characterized in that: The first current collecting member comprises: First set of streaming discs; The second connection portion is formed by extending the outer peripheral edge of the first collecting plate along the first direction, and the second connection portion is inserted into the connection groove and connected to the side of the first connection portion facing the shell.

4. The battery cell according to claim 2, characterized in that: The cover plate assembly comprises: Cover, including: Cover piece; The third connection part is formed by extending the periphery of the cover sheet along the first direction. The third connection part is inserted into the interior of the shell and connected to the side of the first connection part away from the shell. The end surfaces of the cover sheet and the shell at the opening are flush.

5. The battery cell according to claim 4, characterized in that: A guide section is formed on a side of the third connection portion away from the cover sheet, and along a direction away from the cover sheet, the guide section gradually inclines toward a direction close to the central axis of the cover sheet.

6. The battery cell according to claim 4, characterized in that: A concave portion is formed on the periphery of the cover plate toward the interior of the shell, and the concave portion cooperates with the third connecting portion to form an annular groove.

7. The battery cell according to claim 3, characterized in that: The battery cell further includes a second current collecting member, the second current collecting member including: a second current collecting plate, wherein a through hole is opened in the center of the first current collecting plate along the first direction, the second current collecting plate is installed at the through hole of the first current collecting plate, and the first current collecting plate and the second current collecting plate are spaced apart; A guide post is connected to the second current collecting plate, and the guide post is connected to the cover plate assembly.

8. The battery cell according to claim 7, characterized in that: The battery core also includes a winding core, which is arranged inside the shell. A first pole ear and a second pole ear are formed on the side of the winding core facing the opening. The first current collecting disk is connected to the first pole ear, and the second current collecting disk is connected to the second pole ear.

9. The battery cell according to claim 8, characterized in that: The battery core further comprises a sealing mandrel, and the sealing mandrel comprises: The shaft rod is a tubular structure with a hollow interior and two through ends, and a plurality of through holes are formed on the shaft rod along its radial direction; A sealing head connected to one end of the shaft; The shaft rod passes through the cover plate assembly, the second current collecting member extends into the interior of the winding core, and the sealing head is sealed and fixedly connected to a side of the cover plate assembly away from the shell; or The shaft rod penetrates a side wall portion of the shell body that is arranged opposite to the opening and extends into the interior of the winding core, and the sealing head is sealed and fixedly connected to a side wall portion of the shell body that is arranged opposite to the opening.

10. A battery pack, characterized in that: The battery pack comprises a plurality of battery cells as claimed in any one of claims 1 to 9.

11. A vehicle, characterized in that: The vehicle includes the battery pack as claimed in claim 10.

12. A method for processing a battery core, characterized in that: The battery cell processing method is used to process the battery cell according to any one of claims 1 to 9, and the battery cell processing method comprises: Disposing a housing so that the housing has an opening along a first direction; A first current collecting component is arranged inside the housing; Bend a portion of the shell toward the inside of the shell at the opening to form a first connecting portion; connecting the first current collecting member to the first connecting portion; A cover plate assembly is arranged at the opening, and the cover plate assembly is connected to the first connecting portion.

13. The battery core processing method according to claim 12, characterized in that: A portion of the shell is bent toward the inside of the shell at the opening to form a first connecting portion, comprising: The first connection portion is extended along the first direction and spaced apart from the shell, so that a connection groove is formed between the first connection portion and the shell.

14. The battery core processing method according to claim 13, characterized in that: A first current collecting component is arranged inside the housing, comprising: Processing the first current collecting member so that the first current collecting member includes a first current collecting plate and a second connecting portion connected to each other, and the second connecting portion extends along the first direction; Connecting the first current collecting member to the first connecting portion includes: The second connection portion is connected to a side of the first connection portion facing the housing in the connection slot.

15. The battery core processing method according to claim 13, characterized in that: A cover plate assembly is arranged at the opening, and the cover plate assembly is connected to the first connecting portion, including: Processing the cover plate assembly so that the cover plate assembly includes a cover plate, the cover plate includes a cover sheet and a third connecting portion connected to each other, and the third connecting portion extends along the first direction; The third connection portion is inserted into the shell body so as to be connected with the side of the shell body which is away from the first connection portion, and the cover sheet is flush with the end surface of the shell body at the opening.

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