Battery module and battery pack

Abstract

The utility model relates to a battery module and a battery pack, the battery module comprises cylindrical battery cells, a busbar and an acquisition wire harness, each cylindrical battery cell comprises a positive terminal and a negative terminal, and the busbar is used for connecting the adjacent cylindrical battery cells. In the height direction of the battery module, at least part of the structure of the acquisition wire harness is located between the cylindrical battery cell and the busbar, and the positive terminal or the negative terminal is welded with the acquisition wire harness and the busbar through the same welding spot. When the cylindrical battery cell, the busbar and the acquisition wire harness of the battery module need to be electrically connected, the acquisition wire harness is positioned between the cylindrical battery cell and the busbar, so that the cylindrical battery cell, the busbar and the acquisition wire harness can be integrally welded through one welding spot, the welding frequency is reduced, automatic welding is facilitated, the production efficiency can be improved, and the production cost is reduced. And the space utilization rate of the busbar is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of power batteries, in particular to a battery module and a battery pack. Background Art

[0002] A battery pack typically contains multiple cells for storing electrical energy. Adjacent cells are connected via a busbar, which is welded to the positive and negative terminals of the adjacent cells, allowing for series or parallel connection of the cells. To collect information such as cell voltage, a data collection harness is typically welded to the busbar. This harness collects this information and transmits it to the battery management system (BMS). However, due to the small size of the busbar, it's difficult to weld the data collection harness to the busbar after welding it to the positive and negative terminals of the cells, hindering automated welding. Utility Model Content

[0003] The present application provides a battery module and a battery pack for solving the problem of inconvenient welding of the collection harness and the bus bar.

[0004] In a first aspect, the present application provides a battery module comprising cylindrical cells, a busbar, and a collection harness. The cylindrical cells include positive and negative terminals, and the busbar is used to connect adjacent cylindrical cells. Along the height of the battery module, at least a portion of the collection harness is located between the cylindrical cells and the busbar, and the positive or negative terminal is welded to the collection harness and the busbar at the same weld point.

[0005] In this solution, when the cylindrical cells, bus and collection harness of the battery module need to be electrically connected, the collection harness is placed above the positive terminal or negative terminal of the cylindrical cell along the height direction of the battery module, and the bus is then placed above the collection harness, that is, the collection harness is located between the cylindrical cell and the bus, and then the cylindrical cell, bus and collection harness can be welded together through one welding point, which is beneficial to reduce the number of welding times, facilitates automated welding, and thus can improve production efficiency and improve the space utilization on the bus.

[0006] In this solution, the negative terminal is located at the center of the cylindrical battery core, and the positive terminal is located at the periphery of the negative terminal and is annular.

[0007] The busbar includes a first connecting end and a second connecting end connected to each other, the first connecting end is welded to the negative terminal of the cylindrical battery cell, and the second connecting end is welded to the positive terminal of the adjacent cylindrical battery cell and the collection harness at the same welding point.

[0008] In this solution, the outer contour of the first connecting end is an arc shape, and the outer contour of the second connecting end is a rectangle.

[0009] In this solution, both the first connection end and the second connection end are planar structures.

[0010] In this solution, the ratio of the connection area S1 between the second connection end and the positive terminal to the surface area S2 of the top surface of the cylindrical battery cell satisfies: 1 / 6≤S1 / S2≤1 / 4.

[0011] In this embodiment, the busbar further includes a connecting portion for connecting the first connecting end and the second connecting end, and the connecting portion protrudes relative to the first connecting end and the second connecting end so that there is a gap between the connecting portion and the cylindrical battery cell along the height direction of the battery module.

[0012] In this solution, there is a positioning structure between adjacent cylindrical battery cells, the positioning structure is provided with a protrusion, the connecting portion includes a mounting hole, and the protrusion cooperates with the mounting hole.

[0013] In this solution, the connecting portion is provided with an outwardly extending extension portion, the projection of the extension portion is located between adjacent cylindrical battery cells, and the mounting hole is provided in the extension portion.

[0014] In this solution, the connecting portion further includes a notch portion.

[0015] In a second aspect, the present application provides a battery pack comprising a housing, a battery management system, and a battery module, wherein the battery module is electrically connected to the battery management system, and both the battery management system and the battery module are located within the housing. The battery module is the battery module described above.

[0016] It should be understood that the foregoing general description and the following detailed description are merely illustrative and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A schematic structural diagram of a battery pack provided in this application in a specific embodiment;

[0018] Figure 2 An exploded view of a battery module provided in this application in a specific embodiment;

[0019] Figure 3 This is a schematic diagram of the structure of the cylindrical battery cell, busbar and collection harness provided in this application;

[0020] Figure 4 This is a schematic diagram of the structure of the protrusion and the mounting hole provided in this application;

[0021] Figure 5 This is a schematic structural diagram of a busbar provided in this application in a specific embodiment;

[0022] Figure 6 This is a top view of the cylindrical battery cell provided in this application.

[0023] Description of reference numerals:

[0024] 1-Battery module;

[0025] 11- cylindrical battery cell;

[0026] 111-negative terminal;

[0027] 112-positive terminal;

[0028] 113- raised portion;

[0029] 12-busbar;

[0030] 121-first connection end;

[0031] 122-second connection end;

[0032] 123-connecting part;

[0033] 123a-mounting hole;

[0034] 123b-notch;

[0035] 123c- extension;

[0036] 13-collection harness;

[0037] 2-Battery pack;

[0038] 21-shell.

[0039] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application. DETAILED DESCRIPTION

[0040] In order to better understand the technical solution of the present application, the embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0041] In a specific embodiment, the present application is further described in detail below through specific embodiments and in conjunction with the accompanying drawings.

[0042] It should be clear that the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0043] The terms used in the embodiments of the present application are for the purpose of describing specific embodiments only and are not intended to limit the present application. The singular forms "a", "an", "the" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise.

[0044] It should be understood that the term "and / or" as used herein is merely a description of the relationship between associated objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A exists alone, A and B exist simultaneously, or B exists alone. Furthermore, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0045] It should be noted that the directional words such as "upper", "lower", "left", and "right" described in the embodiments of the present application are described based on the angles shown in the accompanying drawings and should not be understood as limiting the embodiments of the present application. In addition, in the context, it should be understood that when it is mentioned that an element is connected to another element "on" or "under", it can not only be directly connected to the other element "on" or "under", but also be indirectly connected to the other element "on" or "under" through an intermediate element.

[0046] The present application embodiment provides a battery module 1, such as Figure 1-Figure 3 As shown, the battery module 1 includes cylindrical cells 11, busbars 12, and a collection harness 13. The cylindrical cells 11 include positive and negative terminals 112 and 111, and the busbars 12 are used to connect adjacent cylindrical cells 11. Along the height of the battery module 1, at least part of the collection harness 13 is located between the cylindrical cells 11 and the busbars 12, and the positive or negative terminals 112, 111, and the collection harness 13 and busbars 12 are welded to the same spot.

[0047] In this embodiment, the bus 12 is a conductive material, and the bus 12 is used to connect multiple cylindrical battery cells 11 in series or in parallel. One end of the collection harness 13 is used to connect to the cylindrical battery cell 11 and the bus 12, and the other end of the collection harness 13 is used to connect to the battery management system (BMS), so that information such as the voltage and temperature of the cylindrical battery cell 11 can be collected in real time, which is beneficial to prevent the cylindrical battery cell 11 from being overcharged or over-discharged during the charging and discharging process of the cylindrical battery cell 11, thereby improving the safety of the battery module 1.

[0048] When the cylindrical battery cell 11, the busbar 12 and the collection harness 13 of the battery module 1 need to be electrically connected, the collection harness 13 is placed above the positive terminal 112 or the negative terminal 111 of the cylindrical battery cell 11 along the height direction of the battery module 1, and the busbar 12 is then placed above the collection harness 13, that is, the collection harness 13 is located between the cylindrical battery cell 11 and the busbar 12, and then the cylindrical battery cell 11, the busbar 12 and the collection harness 13 can be welded together through one welding point, which is beneficial to reduce the number of welding times, facilitates automated welding, and thus can improve production efficiency and improve the space utilization on the busbar 12.

[0049] In one possible implementation, Figure 3 and Figure 6 As shown, the negative terminal 111 is located at the center of the cylindrical battery cell 11, and the positive terminal 112 is located on the periphery of the negative terminal 111 and is annular. Figure 3 As shown, the busbar 12 includes a first connection end 121 and a second connection end 122 connected to each other. The first connection end 121 is welded to the negative terminal 111 of the cylindrical battery cell 11, and the second connection end 122 is welded to the positive terminal 112 of the adjacent cylindrical battery cell 11 and the collection harness 13 at the same welding point.

[0050] During the electrical connection of the cylindrical cells 11, busbar 12 and collection harness 13 of the battery module 1, the cylindrical cells 11 include adjacent first and second cylindrical cells, the first connection end 121 of the busbar 12 is welded to the negative terminal 111 of the first cylindrical cell via a welding spot, and the second connection end 122 is welded to the positive terminal 112 of the second cylindrical cell and the collection harness 13 via a welding spot, so that the first cylindrical cell and the second cylindrical cell are connected in series via the busbar 12. Since the area of ​​the positive terminal 112 of the cylindrical cell 11 is larger than the area of ​​its negative terminal 111, welding the collection harness 13 to the positive terminal 112 of the cylindrical cell 11 is beneficial to improving the reliability and stability of the electrical connection among the second connection end 122, the collection harness 13 and the cylindrical cell 11. In one possible embodiment, as Figure 3 and Figure 5 As shown, the outer contour of the first connecting end 121 is an arc shape, and the outer contour of the second connecting end 122 is a rectangle.

[0051] In this embodiment, the outer contour of the first connection end 121 is an arc, which helps improve the compatibility of the first connection end 121 with the negative terminal 111, thereby improving the reliability and stability of the connection between the first connection end 121 and the negative terminal 111. In addition, the outer contour of the second connection end 122 of the busbar 12 is a rectangle, which can be used to avoid the first connection end 121 of the adjacent busbar 12, reducing the risk of creepage between two adjacent busbars 12 and improving the safety of the battery module 1. At the same time, without reducing the area of ​​the second connection end 122, compared with the second connection end 122 having other shapes, the projection of the second connection end 122 in a rectangular shape on the positive terminal 112 has a larger area, thereby increasing the welding area of ​​the positive terminal 112, the second connection end 122 and the collection harness 13 welded through the same welding point, further improving the reliability and stability of the welding of the second connection end 122, the positive terminal 112 and the collection harness 13, thereby improving the reliability and stability of the welding of the cylindrical battery cell 11, the bus 12 and the collection harness 13.

[0052] Specifically, the busbar 12 includes an adjacent first busbar and a second busbar. The negative terminal 111 of the above-mentioned first cylindrical battery cell is connected to the first connection end 121 of the first busbar, the positive terminal 112 of the above-mentioned second cylindrical battery cell is connected to the second connection end 122 of the first busbar, and the first connection end 121 of the second busbar is connected to the negative terminal 111 of the second cylindrical battery cell. The second connection end 122 of the first busbar is rectangular and can avoid the first connection end 121 of the second busbar with an arc-shaped outer contour.

[0053] In one possible implementation, Figure 5 As shown, the first connection end 121 and the second connection end 122 are both planar structures, which is beneficial to improving the convenience of connecting the first connection end 121 with the negative terminal 111 and improving the convenience of connecting the second connection end 122 with the positive terminal 112.

[0054] In one possible implementation, Figure 3 As shown, the ratio of the connection area S1 between the second connection end 122 and the positive terminal 112 to the surface area S2 of the top surface of the cylindrical battery cell 11 satisfies the following: 1 / 6≤S1 / S2≤1 / 4. The area ratio can be 1 / 6, 1 / 5.8, 1 / 5.6, 1 / 5.5, 1 / 5.4, 1 / 5.2, 1 / 5, 1 / 4, etc.

[0055] In this embodiment, when the ratio of the connection area S1 between the second connection end 122 and the positive terminal 112 to the surface area S2 of the top surface of the cylindrical battery cell 11 is too small, that is, the connection area between the positive terminal 112, the bus 12 and the collection harness 13 is too small, so that the connection area of ​​the second connection end 122, the positive terminal 112 and the collection harness 13 is small, which is inconvenient for welding the three and easily leads to the risk of poor welding; when the ratio of the connection area S1 between the second connection end 122 and the positive terminal 112 to the surface area S2 of the top surface of the cylindrical battery cell 11 is too large, that is, the surface area of ​​the second connection end 122 is too large, there is a risk of creepage between the second connection end 122 and the first connection end 121 of the adjacent bus 12 connected to the cylindrical battery cell 11, and the risk of short circuit. Therefore, in this embodiment, 1 / 6≤S1 / S2≤1 / 4 is satisfied, so that the connection area of ​​the second connection end 122, the positive terminal 112, and the collection harness 13 is moderate, which is convenient for welding the three together, and there is no possibility of creepage between the second connection end 122 and the first connection end 121 of the adjacent bus 12 connected to the cylindrical battery cell 11, thereby improving the safety of the battery module 1.

[0056] In one possible implementation, Figure 3 and Figure 5 As shown, the busbar 12 also includes a connecting portion 123 for connecting the first connecting end 121 and the second connecting end 122. The connecting portion 123 protrudes relative to the first connecting end 121 and the second connecting end 122 so that there is a gap between the connecting portion 123 and the cylindrical battery cell 11 along the height direction of the battery module 1.

[0057] In this embodiment, the connection portion 123 protrudes relative to the first connection end 121 and the second connection end 122 along the height of the battery module 1, which helps to enhance the strength of the busbar 12 and, in turn, improves the structural reliability of the battery module 1. Furthermore, the connection portion 123 protrudes relative to the first connection end 121 and the second connection end 122 along the height of the battery module 1, positioning the connection portion 123 away from the cylindrical battery cell 11 and reducing the risk of a short circuit between the connection portion 123 and the cylindrical battery cell 11.

[0058] In one possible implementation, Figure 3 and Figure 4 As shown, there is a positioning structure between adjacent cylindrical battery cells 11, the positioning structure is used to position adjacent cylindrical battery cells 11, the positioning structure is provided with a protrusion 113, the connecting portion 123 includes a mounting hole 123a, and the protrusion 113 cooperates with the mounting hole 123a.

[0059] In this embodiment, an insulating positioning structure is provided between adjacent cylindrical battery cells 11. The positioning structure is used to position the busbar 12 and to insulate and space adjacent cylindrical battery cells 11, thereby preventing the adjacent cylindrical battery cells 11 from creeping electricity through the outer wall and reducing the risk of short circuit. The positioning structure is provided with a protrusion 113 extending in the height direction of the battery module 1. When installing the busbar 12, the relative position of the busbar 12 and the cylindrical battery cell 11 can be accurately determined by cooperating with the protrusion 113 and the mounting hole 123a of the busbar 12, which facilitates positioning and installation. At the same time, it can improve the accuracy of the connection between the first connection end 121 and the negative terminal 111 of the cylindrical battery cell 11, and improve the accuracy of the connection between the second connection end 122 and the positive terminal 112 of the adjacent cylindrical battery cell 11, thereby improving assembly efficiency. At the same time, the connecting portion 123 is raised relative to the first connecting end 121 and the second connecting end 122, and has a gap with the cylindrical battery cell 11 along the height direction of the battery module 1, so that the connecting portion 123 can avoid the positioning structure, reducing the risk of interference between the bus 12 and the positioning structure.

[0060] The positioning structure may be an insulating component disposed between two adjacent cylindrical battery cells 11 and fixedly connected to the housing.

[0061] In one possible implementation, Figure 3-Figure 5 As shown, the connecting portion 123 is provided with an outwardly extending extension portion 123c. The projection of the extension portion 123c is located between adjacent cylindrical battery cells 11. The mounting hole 123a is provided in the extension portion 123c. When the mounting hole 123a provided in the extension portion 123c is matched with the protrusion 113, the extension portion 123c extending relative to the first connection end 121 and the second connection end 122 can further reduce the risk of interference between the busbar 12 and the positioning structure.

[0062] In one possible implementation, Figure 5 As shown, the connecting portion 123 further includes a notch portion 123b.

[0063] In this embodiment, the connecting portion 123 is provided with a notch portion 123b extending inward, which is beneficial to enhancing the buffering performance of the bus 12. That is, when the battery module 1 vibrates, the notch portion 123b can release the stress during the vibration process, thereby reducing the risk of deformation of the bus 12 due to vibration of the battery module 1, and further reducing the risk of damage to the positive terminal 112 and the negative terminal 111 due to deformation of the bus 12.

[0064] The present application also provides a battery pack, such as Figure 1As shown, the battery pack is used for new energy vehicles and includes a housing 21, a battery management system, and a battery module 1. The battery module 1 is electrically connected to the battery management system, and both the battery management system and the battery module 1 are located within the housing 21. The battery module 1 is the battery module 1 in any of the above embodiments.

[0065] When the battery module 1 is used in a battery pack, the collection harness 13 is located between the cylindrical cell 11 and the busbar 12. This allows the cylindrical cell 11, busbar 12, and collection harness 13 to be welded together at a single weld point. This reduces the number of welds required for the battery module 1, facilitates automated welding, and improves the production efficiency of the battery module 1, thereby improving the production efficiency of the battery pack. Furthermore, the busbar 12 enables series and parallel connection of multiple cylindrical cells 11, which helps increase the capacity of the battery pack.

[0066] The above description is merely a specific implementation of the embodiments of the present application, but the scope of protection of the embodiments of the present application is not limited thereto. Any changes or substitutions within the technical scope disclosed in the embodiments of the present application shall be included in the scope of protection of the embodiments of the present application. Therefore, the scope of protection of the embodiments of the present application shall be based on the scope of protection of the claims.

Claims

1. A battery module, characterized in that: The battery module comprises: A cylindrical battery cell, comprising a positive terminal and a negative terminal; A busbar, the busbar being used to connect adjacent cylindrical battery cells; A collection harness, along the height direction of the battery module, at least part of the structure of the collection harness is located between the cylindrical battery cell and the bus bar, and the positive terminal or the negative terminal is welded to the collection harness and the bus bar through the same welding point.

2. The battery module according to claim 1, wherein: The negative terminal is located at the center of the cylindrical battery core, and the positive terminal is located at the periphery of the negative terminal and is annular; The busbar includes a first connecting end and a second connecting end connected to each other, the first connecting end is welded to the negative terminal of the cylindrical battery cell, and the second connecting end is welded to the positive terminal of the adjacent cylindrical battery cell and the collection harness at the same welding point.

3. The battery module according to claim 2, characterized in that: The outer contour of the first connecting end is an arc shape, and the outer contour of the second connecting end is a rectangle.

4. The battery module according to claim 2, wherein: The first connection end and the second connection end are both planar structures.

5. The battery module according to claim 2, characterized in that: The ratio of a connection area S1 between the second connection end and the positive terminal to a surface area S2 of the top surface of the cylindrical battery core satisfies: 1 / 6≤S1 / S2≤1 / 4.

6. The battery module according to any one of claims 2 to 5, characterized in that: The busbar further includes a connecting portion for connecting the first connecting end and the second connecting end, wherein the connecting portion protrudes relative to the first connecting end and the second connecting end so that a gap exists between the connecting portion and the cylindrical battery cell along the height direction of the battery module.

7. The battery module according to claim 6, characterized in that: There is a positioning structure between adjacent cylindrical battery cells, the positioning structure is provided with a protrusion, the connecting portion includes a mounting hole, and the protrusion cooperates with the mounting hole.

8. The battery module according to claim 7, characterized in that: The connecting portion is provided with an outwardly extending extension portion, the projection of the extension portion is located between adjacent cylindrical battery cells, and the mounting hole is provided in the extension portion.

9. The battery module according to claim 6, wherein: The connecting portion further includes a notch portion.

10. A battery pack, characterized in that: The battery pack includes: case; Battery management system; a battery module, the battery module being electrically connected to the battery management system, the battery management system and the battery module being both located within the housing; Wherein, the battery module is the battery module according to any one of claims 1-9.

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