Conductive connecting piece, connecting row and cylindrical battery cell module thereof

Abstract

The embodiment of the specification discloses a conductive connecting piece, a connecting row and a cylindrical battery cell module, and particularly relates to the technical field of cylindrical batteries, wherein the conductive connecting piece has multiple connecting end portions, at least one of the connecting end portions is defined with a welding area on the upper surface of the connecting end portion, the welding area is suitable for laser welding to the electrode end face of a cylindrical single battery cell, the upper surface of the at least one connecting end portion is upwardly protruded to form a retaining wall structure which generally surrounds the welding area, the retaining wall structure is used for forming a protective barrier around the welding area, the conductive connecting piece is integrally formed through stamping, the retaining wall structure is formed through forging of the at least one connecting end portion, each of the connecting end portions comprises an end edge portion and two wing edge portions which are adjacent to the end edge portion and opposite to each other, the retaining wall structure comprises a first retaining wall which is formed by upwardly bending the end edge portion and a second retaining wall which is formed by upwardly bending the wing edge portion, and the welding connection process of the conductive connecting piece is safer.

Description

Technical Field

[0001] This application relates to the field of cylindrical battery technology, specifically to a conductive connector, a connector bar, and a cylindrical battery cell module thereof. Background Technology

[0002] There are various cell structures on the market, such as prismatic cells, pouch cells, or cylindrical cells. To assemble a module from individual cells, conductor connectors are needed for series and parallel connections. For example, Chinese patent CN116683125A, published on September 1, 2023, discloses a busbar assembly, a battery module, and a battery pack. This busbar assembly belongs to the aforementioned conductor connector type, specifically including a positive electrode busbar, a negative electrode busbar, and a series busbar. One end of the positive electrode busbar is connected to the positive terminal of the cylindrical power battery module, one end of the negative electrode busbar is connected to the negative terminal of the cylindrical power battery module, and the series busbar is used to connect two adjacent cylindrical power battery modules in series to form a battery pack.

[0003] In the above-mentioned solutions, there are various connection processes between the battery cell and the busbar, such as laser welding, electric welding, and ultrasonic welding. Aluminum-cased cylindrical battery cells typically use laser welding to connect the busbars. However, laser welding presents problems with laser radiation and high-temperature spatter. For example, the positive electrode (and sometimes negative electrode) of a cylindrical battery cell usually has a sealing ring structure. The radiated laser and high-temperature spatter can burn the sealing ring, severely damaging it and rendering it ineffective. If the battery cell leaks, it will pose a safety hazard. Utility Model Content

[0004] In view of this, embodiments of this specification provide a conductive connecting piece, a connecting bar, and a cylindrical battery cell module thereof to solve the above-mentioned technical problems.

[0005] Specifically, the embodiments of this specification provide the following technical solutions:

[0006] A conductive connector has a plurality of connecting ends, at least one of which defines a welding area on its upper surface suitable for laser welding to the electrode face of a cylindrical single cell; the upper surface of the at least one connecting end protrudes upward to form a retaining wall structure that substantially surrounds the welding area, the retaining wall structure serving to form a protective barrier around the welding area.

[0007] To optimize the above solution, the following technical measures were also adopted:

[0008] In one embodiment, the conductive connecting piece is integrally stamped, and the retaining wall structure is formed by forging at least one connecting end.

[0009] In one embodiment, each of the at least one connecting end includes an end edge and two flanges adjacent to the end edge and opposite to each other; the retaining wall structure includes a first retaining wall formed by bending the end edge upward and a second retaining wall formed by bending the flanges upward, the two second retaining walls being disposed at both ends of the first retaining wall and being substantially perpendicular to the first retaining wall.

[0010] In one embodiment, the conductive connecting piece is Z-shaped bent to form two connecting ends and a stepped transition portion connecting the two connecting ends, and the two second retaining walls, the first retaining wall, and the transition portion together form the retaining wall structure.

[0011] In one embodiment, one of the two connecting ends is connected to the terminal of a single battery cell, and the other of the two connecting ends is connected to the electrode end face of another single battery cell surrounding the terminal of the terminal. A clearance space is formed below one of the two connecting ends to avoid the electrode end face of the single battery cell.

[0012] In one embodiment, a collar structure for fitting onto the corresponding cell terminal is formed on one of the two connection ends, and the collar structure is welded to the cell terminal.

[0013] As one embodiment, an overlap surface corresponding to the welding area is formed on the lower surface of the at least one connection end, the overlap surface being adapted to overlap the corresponding single cell electrode face before welding in the welding area.

[0014] Another type of connector is disclosed, which is used for conductive connection of multiple individual cells in a cylindrical cell module, including the aforementioned conductive connector piece.

[0015] In one embodiment, the device includes a first connecting piece, a second connecting piece, and a third connecting piece, each having two connecting ends. The first and second connecting pieces are both conductive connecting pieces. One connecting end of the first connecting piece is connected to the terminal of one of the adjacent individual cells, and the other connecting end is connected to the electrode end face of another individual cell surrounding the terminal. One connecting end of the second connecting piece is connected to the electrode end face of one of the individual cells at one terminal of the cylindrical cell module. One connecting end of the third connecting piece is connected to the terminal of the individual cell at the other terminal of the cylindrical cell module.

[0016] Another cylindrical battery cell module is disclosed, comprising multiple individual battery cells and a connecting strip for realizing the conductive connection of the multiple individual battery cells.

[0017] Compared with the prior art, the beneficial effects that at least one technical solution adopted in the embodiments of this specification can achieve include at least:

[0018] Firstly, by processing a retaining wall structure that substantially surrounds the welding area on at least one connecting end of the aforementioned conductive connecting piece, a protective barrier is formed around the welding area. This prevents laser radiation or spatter from escaping to the outside during same-side welding, typically escaping to the sealing ring between the cell electrode and the housing, thereby burning the sealing ring.

[0019] Both of these components are made by integrally molding conductive connecting pieces, eliminating the need for additional tooling to shield the welding area. This simplifies the cell assembly process and reduces tooling costs. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the conductive connecting piece in Embodiment 1 of this application;

[0022] Figure 2 This is a schematic diagram of the cylindrical battery cell module in Embodiment 1 of this application;

[0023] Figure 3 This is a schematic diagram of the conductive connecting piece in Embodiment 2 of this application;

[0024] Figure 4 This is a schematic diagram of another form of conductive connecting piece in Embodiment 2 of this application.

[0025] Figure Labels

[0026] 1. Conductive connecting piece; 11. Connecting end; 111. Welding area; 113. Retaining wall structure; 1131. First retaining wall; 1132. Second retaining wall; 1133. Transition section; 12. Clearance space; 13. Loop structure; 2. Single cell; 21. Terminal post; 22. Battery end face; 10. Connecting bar; 101. First connecting piece; 102. Second connecting piece; 103. Third connecting piece. Detailed Implementation

[0027] The embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0028] The following specific examples illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. This application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0029] It should be noted that various aspects of embodiments within the scope of the appended claims are described below. It will be apparent that the aspects described herein can be embodied in a wide variety of forms, and any particular structure and / or function described herein is merely illustrative. Based on this application, those skilled in the art will understand that one aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number and aspects set forth herein can be used to implement the device and / or practice the method. Additionally, this device and / or method can be implemented using structures and / or functionalities other than one or more of the aspects set forth herein.

[0030] It should also be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of this application. The drawings only show the components related to this application and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0031] This specification presents an embodiment of a conductive connecting piece, a connecting bar, and a cylindrical battery cell module, which aims to solve the problem in the prior art where laser radiation or spatter escapes to the outside when the conductive connecting piece 1 is laser welded to the electrode end face 22 of the battery cell. Typically, this can burn the sealing ring of the electrode post. This embodiment not only effectively prevents laser radiation and spatter from escaping to the outside, but also eliminates the need for tooling to shield the welding area, thus simplifying the battery cell assembly operation and saving tooling costs.

[0032] The technical solutions provided by the various embodiments of this application are described below with reference to the accompanying drawings.

[0033] like Figure 1As shown, the conductive connecting piece 1 has a plurality of connecting ends 11, and at least one connecting end 11 defines a welding area 111 on its upper surface suitable for laser welding to the electrode end face 22 of the cylindrical single cell 2. The upper surface of the at least one connecting end 11 protrudes upward to form a barrier structure 113 that generally surrounds the welding area 111. The barrier structure 113 is used to form a protective barrier around the welding area 111.

[0034] like Figure 2 As shown, in this embodiment, the conductive connecting piece 1 with the above-mentioned features is used as an example to illustrate the conductive connection between two adjacent individual cells 2 in a cylindrical cell module. The individual cell 2 has a first electrode portion and a second electrode portion at one end. The first electrode portion is configured as a pole post 21 and a sealing ring is sleeved on the first electrode portion. The second electrode portion is configured as an electrode end face 22 surrounding the pole post 21 and is adjacent to the sealing ring. It should be noted that the electrode polarity of the first electrode portion and the second electrode portion is not specified here. That is, the first electrode portion can be a positive electrode or a negative electrode, and correspondingly, the second electrode portion can be a negative electrode or a positive electrode.

[0035] Taking the first connecting piece 101, which is a conductive connecting piece 1, as an example, the first connecting piece 101 has two connecting ends 11. One connecting end 11 needs to be connected to the pole post 21 of one of the two adjacent single cell cells 2, and the other connecting end 11 needs to be connected to the electrode end face 22 of the other single cell cell 2 of the two adjacent single cell cells 2. That is, the welding area 111 on the connecting end 11 needs to be overlapped and welded to the electrode end face 22. Since the electrode end face 22 itself is adjacent to the sealing ring, after the welding area 111 overlaps to the electrode end face 22, it is also adjacent to the pole post 21 and the sealing ring. Therefore, it is difficult to construct a welding fixture between the two to block the laser radiation and / or spatter generated during laser welding.

[0036] In this embodiment, on the one hand, by processing a barrier structure 113 that substantially surrounds the welding area 111 on at least one connecting end 11 of the conductive connecting piece 1, a protective barrier is formed around the welding area 111. This prevents laser or spatter from escaping onto the sealing ring of the electrode post 21 during same-side welding, thus preventing damage to the sealing ring. On the other hand, the barrier structure 113 is integrally formed from the conductive connecting piece 1, eliminating the need for additional tooling to shield the welding area. This simplifies the cell assembly process and reduces tooling costs.

[0037] In this embodiment, the conductive connecting piece 1 is integrally formed by stamping, and the retaining wall structure 113 is formed by forging at least one connecting end 11. More specifically, the retaining wall structure 113 is formed by cold heading at least one connecting end 11. In other embodiments, the conductive connecting piece 1 can also be integrally cast, but the casting process is complex and inefficient, and the formed part still requires post-processing. Therefore, the former is the preferred method in this embodiment.

[0038] Specifically, each of the at least one connecting end 11 includes an end edge and two adjacent and opposite flanges. The retaining wall structure 113 includes a first retaining wall 1131 formed by bending the end edge upwards and a second retaining wall 1132 formed by bending the flanges upwards. The two second retaining walls 1132 are located at both ends of the first retaining wall 1131 and are substantially perpendicular to the first retaining wall 1131. In another embodiment, the second retaining wall 1132 is formed by cold forging the corresponding connecting end 11, and the first retaining wall 1131 is formed by bending the corresponding end edge; this is not a limitation.

[0039] More specifically, in this embodiment, after the conductive connecting piece 1 is stamped, one of the connecting ends 11 is a rectangular end. The connecting end 11 has two opposite corners. Before bending the edge, the two right-angle corners are cut off to form a notch to prevent stress concentration at the right-angle corners during the bending process.

[0040] like Figure 1As shown, in this embodiment, the conductive connecting piece 1 is formed by Z-shaped bending to form two connecting ends 11 and a stepped transition portion 1133 connecting the two connecting ends 11. The barrier structure 113 is formed by the two second barrier walls 1132, the first barrier wall 1131, and the transition portion 1133. At this time, one of the two connecting ends 11 (denoted as the first connecting end) is connected to the terminal post 21 of a single cell 2 (denoted as the first single cell), and the other of the two connecting ends 11 (denoted as the second connecting end) is connected to another single cell 2 (denoted as the second single cell) surrounding the electrode end face 22 of the terminal post 21. A clearance space 12 is formed below the first connecting end to avoid the electrode end face 22 of the first single cell. More specifically, both connecting ends 11 extend horizontally and there is a height difference between the bottom surfaces of the two connecting ends 11. This height difference allows the first connecting end to connect to the terminal post 21 of the first single cell at a higher position, while allowing the second connecting end to connect to the electrode end face 22 of the second single cell at a lower position. This height difference is also the height of the clearance space 12. After the two connecting ends 11 are connected, the existence of the clearance space 12 keeps the first connecting end separate from the electrode end face 22 of the first single cell, so as to avoid the positive and negative terminals of the same cell being connected.

[0041] Here, since the clearance space 12 and the transition portion 1133, which serves as the retaining wall structure 113, are processed in the same step, i.e., by Z-shaped bending, the processing efficiency of the conductive connecting piece 1 and the connecting strip can be improved. In another embodiment, to prevent the first connecting end from simultaneously contacting the positive and negative terminals of the same battery cell, an insulating support is constructed on the first individual battery cell to support the first connecting end. In another embodiment, an insulating sleeve can also be fitted onto the first connecting end to prevent the positive and negative terminals of the same battery cell from simultaneously contacting the first connecting end.

[0042] like Figure 1 As shown, in this embodiment, one of the two connecting ends 11, namely the first connecting end, has a collar structure 13 for fitting onto the corresponding cell 2 terminal 21. The collar structure 13 is welded to the cell 2 terminal 21, optionally using laser welding. Specifically, the first connecting end is constructed as an arc-shaped connecting lug, and a circular connecting hole is formed on the connecting lug, thereby forming the aforementioned collar structure 13. The connecting lug and the connecting hole are arranged coaxially to facilitate processing and positioning.

[0043] In this embodiment, an overlapping surface corresponding to the welding area 111 is formed on the lower surface of at least one connecting end 11. The overlapping surface is adapted to overlap onto the corresponding single cell 2 electrode end face 22 before welding is performed in the welding area 111. Optionally, the overlapping surface is an overlapping plane.

[0044] Based on this, this embodiment further discloses a connecting strip 10, used for conductive connection of multiple individual cells 2 in a cylindrical cell module, including the aforementioned conductive connecting piece 1. Specifically, the connecting strip 10 includes a first connecting piece 101, a second connecting piece 102, and a third connecting piece 103, each with two connecting ends 11. The first connecting piece 101 and the second connecting piece 102 both adopt the aforementioned structure of the conductive connecting piece 1. The first connecting piece 101 is used to connect adjacent individual cells in series in the cylindrical cell module. One connecting end 11 of the first connecting piece 101 is connected to the terminal 21 of one of the adjacent individual cells 2, and the other connecting end 11 is connected to another individual cell 2 in a loop. The second connecting piece 102 is connected to the electrode end face 22 of one electrode of the cylindrical cell module. Optionally, it is connected to the electrode end face 22 of the negative electrode of the cylindrical cell module. The third connecting piece 103 is connected to the electrode end 21 of the other electrode of the cylindrical cell module. Optionally, it is connected to the electrode end face 22 of the positive electrode of the cylindrical cell module.

[0045] In addition, a cylindrical battery cell module is disclosed, including a plurality of individual battery cells 2 and a connection row 10 as described above for realizing the conductive connection of the plurality of individual battery cells 2.

[0046] Example 2

[0047] like Figure 3 As shown, this embodiment is basically the same as embodiment one. The difference is that the conductive connecting piece 1 in this embodiment has two identical connecting ends 11. The conductive connecting piece 1 can be applied to the parallel connection between two cylindrical cell modules. For example, one connecting end 11 is connected to the electrode end face 22 of the single cell 2 at the negative end of one cylindrical cell module, and the other connecting end 11 is connected to the electrode end face 22 of the single cell 2 at the negative end of another cylindrical cell module. A welding area is formed on each connecting end 11, and a barrier structure 113 is constructed to surround the welding area to form a protective barrier to block laser radiation and spatter.

[0048] In another embodiment, the conductive connecting piece 1 has four connecting ends 11, used for parallel connection between cylindrical cell modules whose positive and negative terminals each include multiple individual cells, such as... Figure 4 As shown, each connection end 11 has a welding area and a retaining wall structure 113 that surrounds the welding area. Two connection ends 11 are connected to the electrode surfaces 22 of two individual cells 2 at the negative end of one cylindrical cell module, and the other two connection ends 11 are connected to the electrode surfaces 22 of two individual cells 2 at the negative end of another cylindrical cell module.

[0049] Similarly, the conductive connector 1 can also have other usable forms, which will not be elaborated here.

[0050] In the above embodiments, on the one hand, by processing a baffle structure 113 that substantially surrounds the welding area 111 on at least one connecting end 11 of the conductive connecting piece 1, a protective barrier is formed around the welding area 111, which can prevent laser or spatter from escaping onto the sealing ring on the electrode post 21 and thus burning the sealing ring. On the other hand, the baffle structure 113 is processed by integrally molding the conductive connecting piece 1, eliminating the need for additional tooling to shield the welding area, thus simplifying the cell assembly operation and reducing tooling costs.

[0051] In this specification, the same or similar parts between the various embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, the descriptions of the embodiments described later are relatively simple, and relevant parts can be referred to the descriptions of the foregoing embodiments.

[0052] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A conductive connector having multiple connecting ends, characterized in that: At least one of the upper surfaces of the connecting end defines a welding area suitable for laser welding to the electrode face of the cylindrical cell; The upper surface of at least one connecting end protrudes upward to form a retaining wall structure that generally surrounds the welding area, the retaining wall structure serving to form a protective barrier around the welding area.

2. The conductive connecting piece according to claim 1, characterized in that, The conductive connecting piece is integrally formed by stamping, and the retaining wall structure is formed by forging at least one connecting end.

3. The conductive connecting piece according to claim 1, characterized in that, Each of the at least one connecting end includes an end edge and two flanges adjacent to the end edge and opposite to each other; The retaining wall structure includes a first retaining wall formed by bending the end edge upward and a second retaining wall formed by bending the flange upward. The two second retaining walls are located at both ends of the first retaining wall and are substantially perpendicular to the first retaining wall.

4. The conductive connecting piece according to claim 3, characterized in that, The conductive connecting piece is bent in a Z-shape to form two connecting ends and a stepped transition portion connecting the two connecting ends. The retaining wall structure is formed by the two second retaining walls, the first retaining wall, and the transition portion.

5. The conductive connecting piece according to claim 4, characterized in that, One of the two connection ends is connected to the terminal of a single battery cell, and the other of the two connection ends is connected to the electrode end face of another single battery cell surrounding the terminal of the terminal. A clearance space is formed below one of the two connection ends to avoid the electrode end face of the single battery cell.

6. The conductive connecting piece according to claim 5, characterized in that, One of the two connection ends has a collar structure for fitting onto the corresponding cell electrode post, and the collar structure is welded to the cell electrode post.

7. The conductive connecting piece according to any one of claims 1 to 6, characterized in that, The lower surface of at least one connection end is formed with an overlapping surface corresponding to the welding area, the overlapping surface being adapted to overlap to the corresponding single cell electrode surface before welding in the welding area.

8. A connecting strip, used for conductive connection of multiple individual cells in a cylindrical cell module, characterized in that, Includes the conductive connecting piece as described in claim 1.

9. The connecting bar according to claim 8, characterized in that, It includes a first connecting piece, a second connecting piece, and a third connecting piece, each having two connecting ends, wherein the first connecting piece and the second connecting piece are both made of the aforementioned conductive connecting piece; One end of the first connecting piece is connected to the terminal of one of the adjacent individual cells, and the other end is connected to the electrode end face of another individual cell surrounding the terminal; one end of the second connecting piece is connected to the electrode end face of one of the individual cells of the cylindrical cell module; and one end of the third connecting piece is connected to the terminal of another individual cell of the cylindrical cell module.

10. A cylindrical battery cell module, characterized in that, It includes multiple individual battery cells and a connection bus as described in claim 8 for realizing the conductive connection of the multiple individual battery cells.

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