Busbar assembly, battery module and battery pack

Abstract

Provided in the present application are a busbar assembly, a battery module and a battery pack. The busbar assembly comprises: a busbar group portion, which comprises output busbars and connecting busbars, wherein each output busbar comprises an inter-module welding portion and in-module welding portions, which are connected to each other; and positioning plates, wherein each output busbar is arranged on the side face of a positioning plate facing away from battery cells, the positioning plate is provided with a supporting rib, and the inter-module welding portion abuts against the supporting rib.

Description

A busbar assembly, battery module and battery pack

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on September 12, 2023, with application number 2023224837008. The entire contents of the above application are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of battery technology, and in particular to a bus assembly, a battery module, and a battery pack. Background Art

[0003] A battery pack includes multiple battery modules connected in series. The several battery cells that make up the battery modules are connected as a whole via a busbar assembly. Adjacent busbar assemblies are welded together using copper or aluminum bars to connect the two adjacent battery modules in series. To integrate the various components of the busbar assembly, the prior art often uses an insulating film to bond and fix the various components of the busbar assembly into a whole, or uses a plastic bracket to heat-rivet the various components of the busbar into a whole. However, when two adjacent busbar assemblies are welded in series using copper or aluminum bars, the welded components may burn the insulating film or plastic bracket directly connected to them due to the heat, affecting product yield. Technical issues

[0004] The present application aims to solve the following technical problem: when connecting busbar components in series by welding, how to prevent high-temperature burning during output busbar welding, thereby improving safety and product yield. Technical Solutions

[0005] In the first aspect, the present application provides a busbar assembly for use in a battery module, comprising: a busbar assembly, comprising an output busbar and a connection busbar, with a plurality of connection busbars arranged between two output busbars, the output busbars comprising interconnected inter-module welds and intra-module welds; a positioning plate, the output busbars being disposed on a side of the positioning plate facing away from the battery cells, the positioning plate being provided with support ribs, the inter-module welds abutting against the support ribs. In the second aspect, the present application provides a battery module, comprising the CCS assembly described above.

[0006] In a second aspect, the present application provides a battery module comprising the above-mentioned busbar assembly.

[0007] In the third aspect, the present application provides a battery pack comprising a series row and the above-mentioned battery modules, wherein the series row is used to connect two adjacent battery modules in series; the series row is connected to the welding portion between the modules; a limiting protrusion is provided on the side of the positioning plate away from the battery cell, the limiting protrusion extends in a direction away from the battery cell, and the limiting protrusion is at least on both sides of the series row, and in the direction away from the battery cell, the top surface of the limiting protrusion is higher than the series row. Beneficial effects

[0008] In the present application, the support ribs on the positioning plate can support the output bus upward so that the output bus can be away from the main structure of the positioning plate. Therefore, when the output bus is welded, the output bus is heated and only affects the support ribs, thereby preventing the high temperature of the output bus from burning the main structure of the positioning plate during welding. This can well ensure the structural strength and insulation performance of the main structure of the positioning plate, and ensure the product yield of the bus assembly.

[0009] The battery module of the present application is easy to assemble and has high safety.

[0010] The battery pack of the present application has high safety when welding two adjacent battery modules, and the positioning of the series row of two adjacent battery modules used in series is convenient, and the assembly efficiency is high. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] FIG1 is a schematic diagram of the three-dimensional structure of a busbar assembly provided in an embodiment of the present application;

[0012] FIG2 is a schematic diagram of an exploded structure of a busbar assembly provided in an embodiment of the present application;

[0013] FIG3 is a schematic diagram of the three-dimensional structure of the positive electrode positioning plate provided in an embodiment of the present application;

[0014] FIG4 is a bottom view of the structure of the positive electrode positioning plate provided in an embodiment of the present application;

[0015] FIG5 is a schematic diagram of the three-dimensional structure of the negative electrode positioning plate provided in an embodiment of the present application;

[0016] FIG6 is a bottom view of the structure of the negative electrode positioning plate provided in an embodiment of the present application;

[0017] FIG7 is a schematic diagram of the three-dimensional structure of the positive electrode output row provided in an embodiment of the present application;

[0018] FIG8 is a schematic diagram of the three-dimensional structure of the negative electrode output row provided in an embodiment of the present application;

[0019] FIG9 is a schematic diagram of the assembly structure of the positive electrode output row and the positive electrode positioning plate provided in an embodiment of the present application;

[0020] FIG10 is a schematic diagram of the three-dimensional structure of a battery cell provided in an embodiment of the present application;

[0021] FIG11 is a schematic diagram of the three-dimensional structure of the connection bar provided in an embodiment of the present application.

[0022] Icons: 1. Busbar assembly; 11. FPC; 111. Nickel sheet; 112. NTC; 12. First insulating film; 121. Second welding hole; 13a. Positive output row; 13b. Negative output row; 131. Inter-module welding section; 1311. First hot riveting hole; 132. Intra-module welding section; 133a. Positive connecting piece; 133b. Negative connecting piece; 14. Connecting row; 141. Conductive unit; 1411. Positive portion; 1412. Negative portion Part; 15a, positive positioning plate; 15b, negative positioning plate; 151, positioning groove; 1511, notch; 152, support rib; 1521, longitudinal support part; 1522, transverse support part; 153, first thermal rivet column; 154, second thermal rivet column; 155, electrode hole; 156, annular limiting rib; 157, limiting protrusion; 16, second insulating film; 17, first welding hole; 18, second thermal rivet hole; 20, battery cell; 201, positive terminal; 202, negative terminal. Modes for Carrying Out the Invention

[0023] In one embodiment, the output row is located at the end of the battery module in the length direction; in the same battery module, the intra-module welding portion extends toward the adjacent battery cell, and the thickness of the inter-module welding portion is greater than the thickness of the intra-module welding portion.

[0024] In one embodiment, a positioning groove is provided on the positioning plate, and the inter-module welding portion is embedded in the positioning groove; and the supporting rib is provided on the inner wall of the positioning groove.

[0025] In one embodiment, a first thermal rivet hole is provided through the inter-module welding portion, and a first thermal rivet column cooperating with the first thermal rivet hole is provided in the positioning groove.

[0026] In one embodiment, a first insulating film and a second insulating film are further included, wherein the first insulating film is attached to a side of the arrangement portion facing away from the battery cell; and the second insulating film is attached to a side of the arrangement portion facing the battery cell.

[0027] In one embodiment, second heat rivet holes corresponding to each other are provided through the in-module welding portion, the first insulating film, and the second insulating film, and second heat rivet columns cooperating with the second heat rivet holes are provided on the positioning plate.

[0028] In one embodiment, a side of the positioning plate facing the battery cell is provided with an annular limiting rib for limiting the battery cell, and an electrode hole for exposing the positive and negative ends of the battery cell toward the output row and the connection row is opened in the area surrounded by the annular limiting rib.

[0029] In one embodiment, the supporting rib includes a longitudinal supporting portion and a transverse supporting portion, wherein the longitudinal supporting portion is arranged on the bottom wall of the positioning groove, and the transverse supporting portion is arranged on the inner side wall of the positioning groove.

[0030] In one embodiment, first welding holes are formed through the first insulating film and the second insulating film, and the output bars and the connection bars are exposed through the first welding holes.

[0031] In one embodiment, the busbar assembly further includes an FPC, which is disposed on the first insulating film; a collection nickel sheet is disposed on the FPC, and a second welding hole is provided through the first insulating film, and the second welding hole is used to expose the collection nickel sheet.

[0032] In one embodiment, a notch for accommodating the FPC is formed on a side wall of the positioning groove.

[0033] In one embodiment, in a direction away from the battery core, a maximum distance between the support rib and the output row is smaller than a maximum distance between the support rib and a top surface of the limiting protrusion.

[0034] Please refer to Figures 1 to 11. A busbar assembly is used in cylindrical power battery modules. The structure of the battery cell 20 is shown in Figure 10. The positive terminal 201 and the negative terminal 202 of the battery cell 20 are both arranged toward the side of the busbar assembly 1. The busbar assembly 1 includes an arrangement portion, a first insulating film 12, a second insulating film 16, and positioning plates 15a and 15b. The first insulating film 12 is attached to the side of the arrangement portion facing away from the battery cell 20, and the second insulating film 16 is attached to the side of the arrangement portion facing the battery cell 20. The first insulating film 12 and the second insulating film 16 herein include, but are not limited to, PET films. The first insulating film 12 and the second insulating film 16 shown in Figure 2 are used to bond and fix the various components of the arrangement portion in the upper and lower directions to form an integrated busbar assembly 1 as shown in Figure 1.

[0035] Specifically, the arrangement portion includes output rows 13a, 13b and connecting rows 14. Several connecting rows 14 are arranged between the two output rows 13a, 13b. The output rows include interconnected inter-module welding portions 131 and intra-module welding portions 132. The output rows are arranged on a side of the positioning plate facing away from the battery cell 20. The positioning plate is provided with support ribs 152, and the inter-module welding portions 131 abut against the support ribs 152. In this embodiment, the copper bus or aluminum bus used to connect two adjacent battery modules in series is welded to the inter-module welding portion 131, as shown in Figure 2. The support ribs 152 on the positioning plate can support the output bus upward so that the output bus, i.e., the inter-module welding portion 131, can be away from the main structure of the positioning plate. Therefore, when the inter-module welding portion 131 is welded, the inter-module welding portion 131 is heated and only affects the support ribs 152, thereby preventing the high temperature of the module assembly welding portion from burning the main structure of the positioning plate during welding, which can well ensure the structural strength and insulation performance of the main structure of the positioning plate, and ensure the product yield of the bus assembly 1.

[0036] In this embodiment, the positioning plate is arranged at the output row position, that is, the positioning plate is at the two ends of the bus assembly 1, which can enhance the structural strength of the bus assembly 1 to a certain extent and facilitate the production, transportation and assembly of the bus assembly 1.

[0037] As shown in Figures 2 and 11, the connecting bar 14 includes multiple conductive units 141. Each conductive unit 141 includes a positive electrode portion 1411 and a negative electrode portion 1412 that are interconnected. The conductive units 141 are used to connect two adjacent battery cells 20 in series. Specifically, the positive electrode portion 1411 of the conductive unit 141 is welded to the positive terminal 201 of one battery cell 20, and the negative electrode portion 1412 of the same conductive unit 141 is welded to the negative terminal 202 of the other battery cell 20. Multiple connecting bars 14 are arranged along the length of the battery module.

[0038] In this embodiment, as shown in Figures 2, 7, and 8, the output rows are correspondingly arranged at the two ends of the battery module in the longitudinal direction. The output row at the positive output end of the battery module is the positive output row 13a, and the output row at the negative output end of the battery module is the negative output row 13b. The output rows are provided with a number of connecting pieces equal to the number of conductive units 141 constituting a single connecting row 14. The connecting piece on the negative output row 13b is a negative connecting piece 133b, which is used to connect to the negative terminal 202 of the battery cell 20 at the negative output end of the battery module. The connecting piece on the positive output row 13a is a positive connecting piece 133a, which is used to connect to the positive terminal 201 of the battery cell 20 at the positive output end of the battery module.

[0039] In this embodiment, within a single battery module, the intra-module weld 132 extends toward the adjacent battery cell 20, and the thickness of the inter-module weld 131 is greater than the thickness of the intra-module weld 132. There are four intra-module welds 132, equal in number to the conductive units 141 that comprise a single connecting row 14, and they are arranged one-to-one with the connecting tabs. Specifically, the connecting tab is integrally provided at the end of the intra-module weld 132 facing the battery cell 20.

[0040] Furthermore, as shown in Figures 2 to 6, the positioning plate corresponding to the positive output row 13a is called the positive positioning plate 15a, and the positioning plate corresponding to the negative output row 13b is called the negative positioning plate 15b. Specifically, the positioning plates are provided with positioning slots 151, into which the inter-module welds 131 are embedded; support ribs 152 are provided on the inner walls of positioning slots 151. These positioning slots 151 allow for the output rows to be positioned and connected, facilitating assembly of the two.

[0041] Furthermore, a first heat rivet hole 1311 is provided through the inter-module welding portion 131, and a first heat rivet stud 153 is provided in the positioning groove 151 to cooperate with the first heat rivet hole 1311. The first heat rivet stud 153 and the first heat rivet hole 1311 can achieve precise matching and fixation between the output row and the positioning plate.

[0042] At the same time, corresponding second heat rivet holes 18 are provided through the in-module weld portion 132, the first insulating film 12, and the second insulating film 16, and second heat rivet studs 154 are provided on the positioning plate to cooperate with the second heat rivet holes 18. As shown in Figures 1 and 2, in this embodiment, the area of ​​the positioning plate corresponding to the in-module weld portion 132 is located below the second insulating film 16. The second heat rivet studs 154 here pass through the first insulating film 12 and the second insulating film 16 from bottom to top, thereby achieving a precise connection between the positioning plate and the overall structure consisting of the first insulating film 12, the array portion, and the second insulating film 16.

[0043] As shown in Figures 3 and 5, the support rib 152 includes a longitudinal support portion 1521 and a transverse support portion 1522, wherein the longitudinal support portion 1521 is provided on the bottom wall of the positioning groove 151, and the transverse support portion 1522 is provided on the inner side wall of the positioning groove 151. In this embodiment, preferably, the longitudinal support portion 1521 provides an upward support force for the inter-module welding portion 131 on the bottom wall of the positioning groove 151 to protect the bottom wall of the positioning groove 151 from burning; correspondingly, the transverse support portion 1522 provides a support force for the inter-module welding portion 131 on the inner side wall of the positioning groove 151 in a direction parallel to the bottom wall of the positioning groove 151 to protect the inner side wall of the positioning groove 151 from burning.

[0044] In this embodiment, the layout structure of the longitudinal support portion 1521 on the bottom wall of the positioning groove 151 and the local structure of the transverse support portion 1522 on the inner wall of the positioning groove 151 are preferred implementations. In other embodiments, the layout can be appropriately adjusted as needed to achieve the aforementioned support function for the inter-module welding portion 131.

[0045] As shown in Figures 4 and 6, an annular limiting rib 156 for limiting the battery cell 20 is provided on one side of the positioning plate facing the battery cell 20, and an electrode hole 155 is provided in the area surrounded by the annular limiting rib 156 for exposing the positive terminal 201 and the negative terminal 202 of the battery cell 20 toward the output row and the connecting row 14. The annular limiting rib 156 here is used to limit the clamping of the battery cell 20 as shown in Figure 10. After the busbar assembly 1 and the battery cell 20 are assembled, the positive terminal 201 and the negative terminal 202 of the battery cell 20 at the end of the battery module pass through the electrode hole 155 and abut against the connecting piece of the output row. At the same time, the electrode hole 155 can assist in the positioning and assembly of the busbar assembly 1 and the battery cell 20 during the process of assembling the busbar assembly 1 and the battery cell 20 to form a battery module.

[0046] As shown in Figure 2, first welding holes 17 are provided through the first insulating film 12 and the second insulating film 16, and the output bar and the connecting bar 14 are exposed through the first welding holes 17. The first welding holes 17 here can ensure that the conductive unit 141, that is, the connecting bar 14, is welded to the battery cell 20 while ensuring insulation between other parts of the connecting bar 14 and the battery cell 20, thereby improving the safety of the busbar assembly 1 during use. The first welding holes 17 here can assist in positioning during the assembly process of the busbar assembly 1 and the battery cell 20, which is conducive to improving the assembly accuracy of the busbar assembly 1 and the battery cell 20. In this embodiment, the first welding holes 17 on the first insulating film 12 and the first welding holes 17 on the second insulating film 16 are provided correspondingly.

[0047] As shown in Figures 1 to 3, in order to monitor the battery module, the busbar assembly 1 also includes an FPC11, which is arranged on the first insulating film 12; a collection nickel sheet 111 is provided on the FPC11, and a second welding hole 121 is provided through the first insulating film 12, and the second welding hole 121 is used to expose the collection nickel sheet 111. Optionally, the FPC11 is adhered to a side of the first insulating film 12 away from the arrangement portion. The collection nickel sheet 111 is welded to the arrangement portion through the second welding hole 121 for collecting the voltage signal of the battery module. At the same time, an NTC112 is also provided on the FPC11, and the NTC112 is connected to the arrangement portion through the second welding hole 121 for collecting the temperature signal of the battery module.

[0048] Furthermore, as shown in Figures 2 and 3, a notch 1511 is formed on the sidewall of the positioning groove 151 for accommodating the FPC 11. In this embodiment, the output end of the FPC 11 extends from the positive positioning plate 15a. The notch 1511 formed on the sidewall of the positioning groove 151 on the positive positioning plate 15a can prevent the FPC 11 from interfering with the positive positioning plate 15a and facilitate the positioning and assembly of the FPC 11 on the positive positioning plate 15a.

[0049] It is understandable that when the output end of the FPC 11 extends from the negative electrode positioning plate 15 b , the side wall of the positioning groove 151 on the negative electrode positioning plate 15 b is also provided with the above-mentioned notch 1511 .

[0050] This embodiment also provides a battery module, comprising a battery cell 20 and the aforementioned busbar assembly 1. The busbar assembly 1 and the battery cell 20 of the battery module are easy to assemble and highly safe.

[0051] This embodiment also provides a battery pack comprising a series connection bar (not shown) and the aforementioned battery modules. The series connection bar is used to connect two adjacent battery modules in series. The series connection bar is connected to the inter-module weld 131. A positioning plate is provided with a limiting protrusion 157 on a side facing away from the battery cells 20. The limiting protrusion 157 extends away from the battery cells 20 and is located on at least two sides of the series connection bar. In the direction away from the battery cells 20, the top surface of the limiting protrusion 157 is higher than the series connection bar. As shown in FIG9 , the limiting protrusions 157 on at least two sides of the series connection bar can pre-position the series connection bar, facilitating the positioning and installation of the series connection bar during the series connection of two adjacent battery modules, thereby improving the assembly accuracy of the series connection bar. Preferably, the limiting protrusions 157 are provided at least at the four corners of the positioning slot 151. Along the length of the battery module, a limiting space is formed between two adjacent limiting protrusions 157 to accommodate the series connection bar.

[0052] Furthermore, in the direction away from the battery cell 20, the maximum distance between the support rib 152 and the output row is less than the maximum distance between the support rib 152 and the top surface of the limiting protrusion 157. This arrangement ensures that after the output row is assembled to the support rib 152, the extended protrusion can play a role in positioning the series row.

Claims

1. A busbar assembly, applied to a battery module, comprising: A row group portion, comprising an output row and a connection row (14), wherein a plurality of the connection rows (14) are arranged between two of the output rows, and the output row comprises an inter-module welding portion (131) and an intra-module welding portion (132) that are connected to each other; A positioning plate, the output row is arranged on a side of the positioning plate away from the battery cell (20), a support rib (152) is arranged on the positioning plate, and the inter-module welding portion (131) abuts against the support rib (152).

2. The busbar assembly according to claim 1, wherein: The output row is located at the end of the battery module in the length direction; In the same battery module, the intra-module welding portion (132) is extended toward the battery cell (20) adjacent thereto, and the thickness of the inter-module welding portion (131) is greater than the thickness of the intra-module welding portion (132).

3. The busbar assembly according to claim 2, wherein: The positioning plate is provided with a positioning groove (151), and the inter-module welding portion (131) is embedded in the positioning groove (151); The supporting rib (152) is arranged on the inner wall of the positioning groove (151).

4. The busbar assembly according to claim 3, wherein: A first heat riveting hole (1311) is provided through the inter-module welding portion (131), and a first heat riveting column (153) cooperating with the first heat riveting hole (1311) is provided in the positioning groove (151).

5. The busbar assembly according to claim 3 or 4, further comprising a first insulating film (12) and a second insulating film (16), wherein the first insulating film (12) is adhered to a side of the arrangement portion facing away from the battery cell (20); and the second insulating film (16) is adhered to a side of the arrangement portion facing the battery cell (20).

6. The busbar assembly according to claim 5, wherein: The in-module welding portion (132), the first insulating film (12) and the second insulating film (16) are provided with second heat riveting holes (18) corresponding to each other, and the positioning plate is provided with second heat riveting columns (154) matching with the second heat riveting holes (18).

7. The busbar assembly according to any one of claims 1 to 4, wherein: An annular limiting rib (156) for limiting the battery cell (20) is provided on one side of the positioning plate facing the battery cell (20), and an electrode hole (155) for exposing the positive terminal (201) and the negative terminal (202) of the battery cell (20) toward the output row and the connection row (14) is provided in the area surrounded by the annular limiting rib (156).

8. The busbar assembly according to claim 3 or 4, wherein: The supporting rib (152) comprises a longitudinal supporting portion (1521) and a transverse supporting portion (1522), wherein the longitudinal supporting portion (1521) is arranged on the bottom wall of the positioning groove (151), and the transverse supporting portion (1522) is arranged on the inner side wall of the positioning groove (151).

9. The busbar assembly according to claim 5, wherein: The first insulating film (12) and the second insulating film (16) are penetrated by first welding holes (17), and the output row and the connection row (14) are exposed through the first welding holes (17).

10. The busbar assembly according to claim 5, wherein: The busbar assembly (1) further comprises an FPC (11), wherein the FPC (11) is arranged on the first insulating film (12); A collection nickel sheet (111) is provided on the FPC (11), and a second welding hole (121) is provided through the first insulating film (12), wherein the second welding hole (121) is used to expose the collection nickel sheet (111).

11. The busbar assembly according to claim 10, wherein: A notch (1511) for accommodating the FPC (11) is provided on the side wall of the positioning groove (151).

12. A battery module, comprising the busbar assembly (1) according to any one of claims 1 to 11.

13. A battery pack, comprising a series connection row and the battery module as claimed in claim 12, wherein the series connection row is used to connect two adjacent battery modules in series; The series row is connected to the inter-module welding portion (131); A limiting protrusion (157) is provided on a side of the positioning plate away from the battery cell (20); the limiting protrusion (157) extends in a direction away from the battery cell (20), and the limiting protrusion (157) is at least located on two sides of the series row; in the direction away from the battery cell (20), the top surface of the limiting protrusion (157) is higher than the series row.

14. The battery pack according to claim 13, wherein: In a direction away from the battery core (20), the maximum distance between the support rib (152) and the output row is smaller than the maximum distance between the support rib (152) and the top surface of the limiting protrusion (157).

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