Leading-out bar, battery module and battery pack

Abstract

The utility model belongs to the technical field of batteries, and discloses a leading-out bar, a battery module and a battery pack, the leading-out bar is of an integrally formed structure, the leading-out bar comprises a first main body and a second main body, one end of the first main body is provided with a first connecting part, one end of the second main body is provided with a second connecting part, and the second connecting part and the first connecting part are fixed in a lap joint mode. The second main body and the first main body are made of different conductive metal materials, so that the production cost of the leading-out bar can be reduced, and the overcurrent capability of the leading-out bar can be improved.

Description

Outlets, battery modules and battery packs Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a lead-out bar, a battery module, and a battery pack. Background Technology

[0002] In existing technologies, lead-out bars are typically made of copper and aluminum busbars using ultrasonic welding, friction stir welding, or molecular diffusion welding processes. These welding processes are costly, increasing production costs. Furthermore, existing lead-out bars are prone to issues with poor adhesion between the copper and aluminum busbars at the welding points, thereby reducing the current-carrying capacity of the lead-out bar.

[0003] Therefore, there is an urgent need to propose a low-cost drain with high current carrying capacity to solve the above-mentioned technical problems. Summary of the Invention

[0004] The first objective of this invention is to provide a lead-out bar, a battery module, and a battery pack that can not only reduce the production cost of the lead-out bar but also improve its current carrying capacity.

[0005] Firstly, to achieve this objective, the present invention adopts the following technical solution:

[0006] The lead-out bar is a one-piece molded structure, and includes:

[0007] A first main body, one end of which is provided with a first connecting part;

[0008] The second body has a second connecting part at one end, which overlaps and is fixed to the first connecting part.

[0009] The second body and the first body are made of different conductive metal materials.

[0010] Optionally, the second body includes a first connecting segment, a second connecting segment, a third connecting segment, a first bending segment, and a second bending segment. One end of the first connecting segment is a second connecting part, and the other end of the first connecting segment is connected to the second connecting segment through the first bending segment. The end of the second connecting segment facing away from the first bending segment is connected to the third connecting segment through the second bending segment. The first connecting segment and the third connecting segment extend in opposite directions, and both the first connecting segment and the third connecting segment are arranged parallel to the first body, while the second connecting segment is arranged perpendicular to the first body.

[0011] Optionally, the first body is used to connect with the terminal of the battery cell, and the third connecting section is used to connect with the conductive element; the conductive element includes a conductive nut, the conductive nut includes a third connecting part and a fourth connecting part connected to each other, the third connecting section has a mounting hole, the third connecting part is embedded in the mounting hole, the fourth connecting part is used to be inserted into the support of the battery module, and the third connecting part and the fourth connecting part have a coaxial through hole.

[0012] Optionally, the third connecting part includes a first embedding section and a second embedding section, which are distributed along the axial direction of the third connecting part. The outer diameter of the first embedding section is smaller than that of the second embedding section. The mounting hole is a stepped hole, and the end face of the second embedding section facing the first embedding section fits against the stepped plane of the stepped hole.

[0013] Optionally, the outer wall of at least one of the first and second embedded sections is provided with a knurled structure;

[0014] And / or, the support member is provided with an assembly groove, the assembly groove is prismatic, and the shape of the fourth connecting part is adapted to the shape of the assembly groove.

[0015] Optionally, the lead-out section also includes an insulating layer covering the side of the first connection section facing the battery cell and / or the side of the second connection section facing the battery cell.

[0016] Optionally, the length of both the first connecting part and the second connecting part is L. The first connecting part is provided with a narrowing area in the direction from the second connecting part to the first bending section. The width of the first connecting part is divided into K1 and K2 by the narrowing area, and the distance between the second connecting part and the narrowing area is J, where K1>K2 and J≥L.

[0017] Optionally, the first connecting portion is thinned to form a first mating groove, and the second connecting portion is thinned to form a second mating groove. The first mating groove and the second mating groove are arranged opposite to each other and respectively abut against and accommodate the second connecting portion and the first connecting portion.

[0018] The thickness of the first connecting part is h1, and the thickness of the second connecting part is h2, where h1+h2=H, h1≥15%×H, and h2≥15%×H.

[0019] Secondly, to achieve this objective, the present invention adopts the following technical solution:

[0020] Battery module, including the aforementioned lead-out pins.

[0021] Thirdly, to achieve this objective, the present invention adopts the following technical solution:

[0022] Battery pack, including the battery modules mentioned above.

[0023] The beneficial effects of this utility model are:

[0024] The lead-out bar provided by this utility model is an integrally molded structure, with its first main body and second main body made of different conductive metal materials. One end of the first main body is provided with a first connecting portion, and one end of the second main body is provided with a second connecting portion. The second connecting portion overlaps and is fixed to the first connecting portion, thus eliminating the need for ultrasonic welding, friction stir welding, or molecular diffusion welding of the two conductive metal materials, which helps reduce the production cost of the lead-out bar. Furthermore, the overlapping and fixed structure of the second connecting portion and the first connecting portion ensures close contact between them, improving the current-carrying capacity at the connection point and thus enhancing the current-carrying capacity of the lead-out bar. Attached Figure Description

[0025] Figure 1 is a schematic diagram of the first structure of the lead-out bar provided by this utility model;

[0026] Figure 2 is a structural schematic diagram of the battery module provided by this utility model;

[0027] Figure 3 is a magnified view of part A in Figure 2;

[0028] Figure 4 is a schematic diagram of the second structure of the lead-out bar provided by this utility model;

[0029] Figure 5 is a cross-sectional view of FF in Figure 4;

[0030] Figure 6 is a structural schematic diagram of the support member provided by this utility model;

[0031] Figure 7 is a schematic diagram of the third structure of the lead-out bar provided by this utility model;

[0032] Figure 8 is a partial exploded structural diagram of the battery module provided by this utility model.

[0033] In the picture:

[0034] 1. Lead-out bar; 11. First main body; 111. First connecting part; 12. Second main body; 121. Second connecting part; 122. First connecting section; 1221. Narrowing area; 123. Second connecting section; 124. Third connecting section; 1241. Mounting hole; 125. First bending section; 126. Second bending section; 13. Insulating layer; 2. Battery cell; 21. Terminal post; 3. Conductive nut; 31. Third connecting part; 311. First embedded section; 312. Second embedded section; 32. Fourth connecting part; 33. Through hole; 4. Support member; 41. Assembly groove; 5. Conductive bar; 6. Low voltage acquisition component. Detailed Implementation

[0035] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, not the entire structure.

[0036] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0037] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0038] In the description of this embodiment, the terms "upper," "lower," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0039] This embodiment provides a lead-out busbar that can not only reduce the production cost of the lead-out busbar, but also improve its flow capacity.

[0040] Specifically, as shown in Figure 1, the lead-out bar 1 is an integrally formed structure. The lead-out bar 1 includes a first body 11 and a second body 12. One end of the first body 11 is provided with a first connecting part 111, and one end of the second body 12 is provided with a second connecting part 121. The second connecting part 121 overlaps and is fixed with the first connecting part 111. The second body 12 and the first body 11 are made of different conductive metal materials.

[0041] Since the second connecting part 121 is overlapped and fixed with the first connecting part 111, the need for ultrasonic welding, friction stir welding, or molecular diffusion welding of the two conductive metal materials is eliminated, which helps to reduce the production cost of the lead-out outlet 1. Secondly, the overlapped and fixed structure of the second connecting part 121 and the first connecting part 111 allows for close contact between the two parts, improving the current-carrying capacity at the connection point and thus enhancing the current-carrying capacity of the lead-out outlet 1. Thirdly, the close contact between the second connecting part 121 and the first connecting part 111 reduces the volume of the lead-out outlet 1, especially the volume of the overlapped and fixed area between the first connecting part 111 and the second connecting part 121, which helps to increase the energy density of the battery module.

[0042] In this embodiment, the first body 11 is made of aluminum, and the second body 12 is made of copper. Copper has better electrical conductivity than aluminum. Therefore, compared to a pure aluminum lead-out bar 1, the copper second body 12 in this embodiment provides superior electrical conductivity for the lead-out bar 1. Furthermore, the weight ratio of the first body 11 to the total weight of the lead-out bar 1 is C, where 25% ≤ C ≤ 70%. That is, the weight of aluminum accounts for 25%-70% of the total weight of the lead-out bar 1. Compared to other metal materials, aluminum is relatively inexpensive. Therefore, limiting C to 25%-70% can reduce the production cost of the lead-out bar 1 while ensuring sufficient structural strength and electrical conductivity. Of course, in other embodiments, the first body 11 and the second body 12 can also be made of other conductive metals, such as copper, steel, titanium, or nickel, which will not be listed here.

[0043] In actual production, a composite plate can be prepared first using a rolling process (liquid / solid composite process, hot rolling composite process, or cold rolling composite process), and then the composite plate can be made into lead-out bar 1 through processes such as cutting. The aforementioned rolling process is a well-known technology in this field. During the rolling process, the molecules of the two materials combine with each other, so that the two materials are tightly embedded and fixed at the overlapping position and form a whole. In addition, the composite plate produced by the rolling process has a uniform thickness, which improves the thickness consistency of lead-out bar 1.

[0044] Optionally, the first connecting portion 111 is thinned to form a first mating groove, and the second connecting portion 121 is thinned to form a second mating groove. The first mating groove and the second mating groove are arranged opposite to each other and respectively abut against and accommodate the second connecting portion 121 and the first connecting portion 111. On the one hand, the first main body 11 and the second main body 12 can be mutually limited in the x and z directions. On the other hand, the thickness of the overlapping and fixing area (hereinafter referred to as the overlapping and fixing area) between the first connecting portion 111 and the second connecting portion 121 can be reduced, which is beneficial to improving the energy density of the battery module. Furthermore, the thickness of the first connecting portion 111 is h1, and the thickness of the second connecting portion 121 is h2, wherein h1 + h2 = H, h1 ≥ 15% × H (exemplary, h1 can be 15%, 20%, or 25% of H), and h2 ≥ 15% × H (exemplary, h2 can be 15%, 20%, or 25% of H). This design ensures that the first connecting portion 111 and the second connecting portion 121 have sufficient structural strength, thereby ensuring that the overlapping fixing area has sufficient structural strength. It should be noted that h1 and h2 can be equal or unequal, depending on the actual application requirements.

[0045] Optionally, the second body 12 includes a first connecting segment 122, a second connecting segment 123, a third connecting segment 124, a first bending segment 125, and a second bending segment 126. One end of the first connecting segment 122 is the second connecting part 121, and the other end of the first connecting segment 122 is connected to the second connecting segment 123 through the first bending segment 125. The end of the second connecting segment 123 facing away from the first bending segment 125 is connected to the third connecting segment 124 through the second bending segment 126. The first connecting segment 122 and the third connecting segment 124 extend in opposite directions, and both the first connecting segment 122 and the third connecting segment 124 are arranged parallel to the first body 11. The second connecting segment 123 is arranged perpendicular to the first body 11. In practical applications, a deviation of ±5° between the above parallel and perpendicular arrangements is allowed.

[0046] Further, as shown in Figures 4 and 7, the lengths of the first connecting portion 111 and the second connecting portion 121 are both L. A narrowing region 1221 is provided on the first connecting segment 122. Along the direction from the second connecting portion 121 to the first bending segment 125, the width of the first connecting segment 122 is divided into K1 and K2 by the narrowing region 1221, and the distance between the second connecting portion 121 and the narrowing region 1221 is J, where K1 > K2 and J ≥ L. This design ensures a certain distance between the narrowing region 1221 and the second connecting portion 121, thereby ensuring a certain distance between the overlapping fixing area and the narrowing region 1221, thus ensuring that the overlapping fixing area has sufficient overcurrent capacity. In this embodiment, narrowing regions 1221 are provided on both opposite sides of the first connecting segment 122 in the y-direction. Of course, in other embodiments, a narrowing region 1221 may be provided on one side of the first connecting segment 122 in the y-direction, while the other side may not have a narrowing region 1221, depending on the actual application requirements.

[0047] Optionally, as shown in Figures 1 to 5 and Figure 8, the first main body 11 is used to connect with the terminal 21 of the battery cell 2, and the third connecting section 124 is used to connect with a conductive element. The conductive element includes a conductive nut 3, which includes a third connecting part 31 and a fourth connecting part 32 connected to each other. The third connecting section 124 has a mounting hole 1241, and the third connecting part 31 is embedded in the mounting hole 1241. The fourth connecting part 32 is used to be inserted into the support member 4 of the battery module. The third connecting part 31 and the fourth connecting part 32 have a coaxial through hole 33, so that an external conductive element can be inserted into the through hole 33 to achieve a conductive connection between the external conductive element and the battery cell 2. Furthermore, in actual production, the assembly of the conductive nut 3, the lead-out bar 1, and the support member 4 can be completed by inserting the third connecting part 31 into the mounting hole 1241 and the fourth connecting part 32 into the support member 4. This simplifies the assembly process of the conductive nut 3, the lead-out bar 1, and the support member 4, and helps to improve production efficiency. In addition, in this embodiment, the second main body 12 is made of copper material. Copper material has high hardness, that is, the structural strength of the second main body 12 is high, which improves the feasibility of inserting the third connecting part 31 into the mounting hole 1241.

[0048] Furthermore, the third connecting part 31 includes a first embedding section 311 and a second embedding section 312. The first embedding section 311 and the second embedding section 312 are distributed along the axial direction of the third connecting part 31. The outer diameter of the first embedding section 311 is smaller than the outer diameter of the second embedding section 312. The mounting hole 1241 is a stepped hole. The end face of the second embedding section 312 facing the first embedding section 311 fits against the stepped plane of the stepped hole. Thus, in the axial direction of the third connecting part 31, the third connecting section 124 limits the conductive nut 3, which facilitates the assembly of the lead-out bar 1 and the conductive nut 3.

[0049] Furthermore, at least one of the first embedding section 311 and the second embedding section 312 has a knurled structure on its outer wall, thereby limiting the conductive nut 3 by the third connecting section 124 in the circumferential direction of the third connecting portion 31, and preventing the conductive nut 3 from rotating relative to the third connecting section 124. In this embodiment, the knurled structure is provided on the outer wall of the second embedding section 312. Of course, in other embodiments, the outer wall of the first embedding section 311 may also have a knurled structure; or both the outer walls of the first embedding section 311 and the outer walls of the second embedding section 312 may have knurled structures, depending on the actual application requirements.

[0050] Optionally, as shown in Figures 5 and 6, the support member 4 is provided with an assembly groove 41, which is prismatic in shape. The shape of the fourth connecting part 32 is adapted to the shape of the assembly groove 41, thereby limiting the conductive nut 3 on the circumference of the fourth connecting part 32 and preventing the conductive nut 3 from rotating relative to the support member 4. In this embodiment, the assembly groove 41 is hexagonal prism-shaped. In other embodiments, the assembly groove 41 can also be a triangular prism or a pentagonal prism, etc., which will not be listed here. Of course, in other embodiments, both the assembly groove 41 and the fourth connecting part 32 can be cylindrical in shape. In this case, the support member 4 cannot prevent the conductive nut 3 from rotating.

[0051] Optionally, as shown in Figure 1, the lead-out bar 1 further includes an insulating layer 13. The insulating layer 13 covers the side of the first connecting segment 122 facing the cell 2 and the side of the second connecting segment 123 facing the cell 2, thereby achieving insulation between the first connecting segment 122 and the cell 2, and insulation between the second connecting segment 123 and the cell 2. This ensures that only the first main body 11 of the lead-out bar 1 is electrically connected to the cell 2, which helps to improve the insulation protection capability of the battery module and thus improves the safety of the battery module. It should be noted that in other embodiments, the insulating layer 13 may only cover the side of the first connecting segment 122 facing the cell 2, or only cover the side of the second connecting segment 123 facing the cell 2, depending on the actual positional relationship of the first connecting segment 122, the second connecting segment 123, and the cell 2, as long as the lead-out bar 1 is electrically connected only to the first main body 11.

[0052] The insulating layer 13 is a polymer material layer such as PC (polycarbonate) layer, PET (polyethylene terephthalate) layer or PI (polyimide) layer, which are commonly used in the art. The insulating layer 13 can be fixed to the side of the first connecting section 122 facing the battery cell 2 and the side of the second connecting section 123 facing the battery cell 2 by hot pressing process, or it can be fixed to the side of the first connecting section 122 facing the battery cell 2 and the side of the second connecting section 123 facing the battery cell 2 by adhesive.

[0053] This embodiment also provides a battery module, as shown in Figures 2 and 8. The battery module includes several battery cells 2 and the aforementioned lead-out bar 1. The battery cells 2 are electrically connected by conductive bars 5. Along the current flow direction, the upstreammost battery cell 2 and the downstreammost battery cell 2 each correspond to a lead-out bar 1. The terminal post 21 of each battery cell 2 is welded and fixed to the first body 11 of the corresponding lead-out bar 1. This battery module uses the aforementioned lead-out bar 1, where the second connecting portion 121 of the lead-out bar 1 overlaps and is fixed to the first connecting portion 111. This eliminates the need for ultrasonic welding, friction stir welding, or molecular diffusion welding of two conductive metal materials, reducing the production cost of the lead-out bar 1 and the battery module. Furthermore, the overlapping and fixed structure of the second connecting portion 121 and the first connecting portion 111 allows for close contact between the two portions, improving the current-carrying capacity of the lead-out bar 1, and thus improving the current-carrying capacity of the battery module using this lead-out bar 1.

[0054] In this embodiment, the first body 11 is made of aluminum, and the commonly used electrode post 21 is also made of aluminum. Welding the first body 11 and the electrode post 21, which are made of the same material, can improve their welding strength and reduce the welding difficulty. In this embodiment, the orthographic projection of the electrode post 21 on the cell 2 is located within the orthographic projection of the first body 11 on the cell 2, so that the first body 11 can completely cover the electrode post 21, avoiding short circuits caused by contact between the electrode post 21 and other conductive components. It can also increase the welding area between the first body 11 and the electrode post 21, thereby improving the connection reliability and conductivity of the connection position.

[0055] The battery module also includes a low-voltage acquisition component 6, which is a prior art in the field. For example, the low-voltage acquisition component 6 includes a bracket, a temperature sensor, and a voltage sensor. The temperature sensor and the voltage sensor are both mounted on the bracket, and the probes of the temperature sensor and the voltage sensor are both set on the cell 2, thereby detecting the operating status of the cell 2, such as temperature and voltage.

[0056] This embodiment also provides a battery pack, which includes the battery module described above. The battery pack using the battery module described above has lower production costs and higher current carrying capacity.

[0057] It should be noted that in this embodiment, length refers to the dimension in the x-direction, width refers to the dimension in the y-direction, and thickness refers to the dimension in the z-direction.

[0058] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Those skilled in the art can make various obvious changes, readjustments, and substitutions without departing from the protection scope of this utility model. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.

Claims

1. A lead-out bar, characterized in that, The lead-out bar (1) is an integrally formed structure. The lead-out bar (1) includes: a first body (11), one end of which is provided with a first connecting part (111); a second body (12), one end of which is provided with a second connecting part (121), the second connecting part (121) overlapping and fixed with the first connecting part (111); the second body (12) and the first body (11) are made of different conductive metal materials.

2. The lead-out bar according to claim 1, characterized in that, The second main body (12) includes a first connecting segment (122), a second connecting segment (123), a third connecting segment (124), a first bending segment (125), and a second bending segment (126). One end of the first connecting segment (122) is the second connecting part (121). The other end of the first connecting segment (122) is connected to the second connecting segment (123) through the first bending segment (125). The end of the second connecting segment (123) away from the first bending segment (125) is connected to the third connecting segment (124) through the second bending segment (126). The first connecting segment (122) and the third connecting segment (124) extend in opposite directions. Both the first connecting segment (122) and the third connecting segment (124) are arranged parallel to the first main body (11). The second connecting segment (123) is arranged perpendicular to the first main body (11).

3. The lead-out bar according to claim 2, characterized in that, The first main body (11) is used to connect with the terminal (21) of the battery cell (2), and the third connecting section (124) is used to connect with the conductive element; the conductive element includes a conductive nut (3), the conductive nut (3) includes a third connecting part (31) and a fourth connecting part (32) connected to each other, the third connecting section (124) has a mounting hole (1241), the third connecting part (31) is embedded in the mounting hole (1241), the fourth connecting part (32) is used to be inserted into the support member (4) of the battery module, and the third connecting part (31) and the fourth connecting part (32) have a coaxial through hole (33).

4. The lead-out bar according to claim 3, characterized in that, The third connecting part (31) includes a first embedding section (311) and a second embedding section (312). The first embedding section (311) and the second embedding section (312) are distributed along the axial direction of the third connecting part (31). The outer diameter of the first embedding section (311) is smaller than the outer diameter of the second embedding section (312). The mounting hole (1241) is a stepped hole. The end face of the second embedding section (312) facing the first embedding section (311) is in contact with the stepped plane of the stepped hole.

5. The lead-out bar according to claim 4, characterized in that, The outer wall of at least one of the first embedding section (311) and the second embedding section (312) is provided with a knurled structure; and / or, the support member (4) is provided with an assembly groove (41), the assembly groove (41) is prismatic, and the shape of the fourth connecting part (32) is adapted to the shape of the assembly groove (41).

6. The lead-out bar according to claim 3, characterized in that, The lead-out bar (1) further includes an insulating layer (13) that covers the side of the first connecting segment (122) facing the cell (2) and / or the side of the second connecting segment (123) facing the cell (2).

7. The lead-out bar according to claim 2, characterized in that, The lengths of the first connecting portion (111) and the second connecting portion (121) are both L. The first connecting segment (122) is provided with a narrowing area (1221) in the direction from the second connecting portion (121) to the first bending segment (125). The width of the first connecting segment (122) is divided into K1 and K2 by the narrowing area (1221), and the distance between the second connecting portion (121) and the narrowing area (1221) is J, where K1 > K2 and J ≥ L.

8. The lead-out bar according to claim 1, characterized in that, The first connecting portion (111) is thinned to form a first mating groove, and the second connecting portion (121) is thinned to form a second mating groove. The first mating groove and the second mating groove are arranged opposite to each other and respectively abut against and accommodate the second connecting portion (121) and the first connecting portion (111). The thickness of the first connecting portion (111) is h1, and the thickness of the second connecting portion (121) is h2, wherein h1+h2=H, h1≥15%×H, and h2≥15%×H.

9. A battery module, characterized in that, Includes the lead-out row (1) as described in any one of claims 1-8.

10. A battery pack, characterized in that, Includes the battery module as described in claim 9.

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