Integrated busbar with temperature control function and battery pack

Abstract

The application provides an integrated busbar with temperature control function, which comprises a plastic support, a busbar assembly and an FPC assembly. The busbar assembly comprises series conductive buses and output pole conductive buses. The series conductive buses and the output pole conductive buses are respectively embedded in the plastic support. The FPC assembly is arranged on the surface of the plastic support and is electrically connected with the series conductive buses and the output pole conductive buses. The series conductive buses are welded with the pole posts of two adjacent battery cells. The plastic support is provided with a support bridge for supporting the series conductive buses. At least part of the series conductive buses is closely combined with the upper surface of the support bridge. The plastic support is internally provided with a first liquid cooling channel. The first liquid cooling channel is arranged around the periphery of the series conductive buses. The first liquid cooling channel passes through the inside of the support bridge. The first liquid cooling channel is filled with cooling liquid for heat conduction with the series conductive buses. The application further provides a battery pack.

Description

Technical Field

[0001] This invention relates to the field of battery technology, and in particular to an integrated busbar and battery pack with integrated temperature control function. Background Technology

[0002] Currently, with the increasing demands for driving range in new energy vehicles and the widespread adoption of 2C, 3C, and higher-speed charging technologies, power battery systems are developing towards higher energy density and greater charge / discharge rates. Against this backdrop, lightweight battery pack design and efficient management of the large amounts of heat generated during high-rate charging and discharging have become key challenges for the industry's technological development.

[0003] In existing technologies, the thermal management solutions for battery modules generally adopt a structure in which a liquid cooling plate is independently installed above the integrated busbar (CCS). In this structure, the liquid cooling plate and the integrated busbar are designed separately, meaning that the battery's heating unit, liquid cooling plate, and signal acquisition module (such as the FPC component) are mostly independent and separate components. However, this separate design has many inherent drawbacks: First, the independent installation of each functional component results in a complex battery module structure and a large number of parts, which not only increases the overall weight and volume and reduces the energy density of the battery pack, but also occupies the already limited space resources, thus restricting the improvement of the vehicle's range. Secondly, the split structure results in higher thermal resistance and lower heat transfer efficiency between the liquid cooling plate and the battery cell. Especially during high-rate charging and discharging at 3C and above, the cooling effect on the busbar is very limited, making it difficult to control the temperature of the integrated busbar within a safe range below 60°C, which affects the cycle life and fast charging performance of the battery system. Furthermore, the split structure has the problem of poor temperature uniformity. Thermally conductive adhesive is usually required between the liquid cooling plate and the integrated busbar to improve heat conduction. However, the thermally conductive adhesive is prone to uneven application and the thickness is difficult to control, which generates contact thermal resistance and affects the effective transfer of heat. Furthermore, the split structure means that components such as liquid cooling plates, thermal conductive adhesives, busbars, and FPC modules must be installed independently within the battery pack. The assembly process is cumbersome and requires high precision, which not only increases production costs but also affects assembly efficiency and product consistency and reliability. Summary of the Invention

[0004] The purpose of this invention is to provide an integrated busbar and battery pack with integrated temperature control function, which aims to solve or at least partially solve the shortcomings of the above-mentioned background technology. It integrates liquid cooling channels into the integrated busbar, realizing the integration of heating, heat dissipation and information acquisition functions, significantly reducing the number of parts, simplifying the assembly process of battery modules, effectively reducing the overall volume and weight of battery pack, increasing the energy density of battery pack, improving the assembly efficiency of battery pack, and reducing the production cost of battery pack.

[0005] This invention provides an integrated busbar with integrated temperature control function, including a plastic bracket, a busbar assembly, and an FPC assembly. The busbar assembly includes a series conductive bus and an output conductive bus, which are respectively embedded in the plastic bracket. The FPC assembly is disposed on the surface of the plastic bracket and electrically connected to the series conductive bus and the output conductive bus. The series conductive bus is located on both sides of the plastic bracket along its width direction and is exposed on the upper and lower surfaces of the plastic bracket. The series conductive bus is simultaneously welded to the terminals of two adjacent battery cells. The plastic bracket is provided with a support bridge for supporting the series conductive bus, and at least a portion of the series conductive bus is tightly fitted to the upper surface of the support bridge. A first liquid cooling channel is formed inside the plastic bracket. The first liquid cooling channel is arranged at least around the periphery of the series conductive bus and passes through the interior of the support bridge. The first liquid cooling channel is filled with coolant for heat conduction with the series conductive bus.

[0006] Furthermore, the first liquid cooling channel is manufactured using an air-assisted injection molding process.

[0007] Furthermore, the first liquid cooling channel has two heat-conducting sections and a connecting section connecting the two heat-conducting sections. The two heat-conducting sections are located on both sides of the plastic support along the width direction. The heat-conducting sections are arranged around the periphery of the series conductive busbar and pass through the interior of the support bridge.

[0008] Furthermore, the heat-conducting section is in a continuous S-shape.

[0009] Furthermore, the plastic bracket is provided with a first liquid inlet and a first liquid outlet, which are respectively connected to the ends of the two heat-conducting sections.

[0010] Furthermore, the series-connected busbar has two welded portions that are welded to the terminals of the battery cell and a bent portion that connects the two welded portions. The upper surface of the support bridge is a smooth curved surface, and the lower surface of the bent portion is in close contact with the upper surface of the support bridge.

[0011] Furthermore, the series conductive busbar is made of O-state 1 series aluminum.

[0012] Furthermore, a second liquid cooling channel is provided inside the plastic bracket, and the second liquid cooling channel is located below the FPC assembly.

[0013] Furthermore, the second liquid cooling channel is connected to the first liquid cooling channel.

[0014] The present invention also provides a battery pack including the aforementioned integrated busbar with integrated temperature control function.

[0015] This invention provides an integrated busbar with integrated temperature control function. By creating a first liquid cooling channel inside a plastic bracket and combining the first liquid cooling channel with a support bridge, and by embedding a busbar assembly inside the plastic bracket, the liquid cooling plate, plastic bracket, and busbar assembly are integrated into one unit. This makes the integrated busbar with integrated temperature control function compact in structure, significantly reducing the number of parts and simplifying the assembly process of the battery module. It not only effectively reduces the overall volume and weight of the battery pack and increases the energy density of the battery pack, but also improves the assembly efficiency of the battery pack and reduces the production cost of the battery pack. Through the cooperation of the plastic bracket, coolant, busbar assembly, and FPC assembly, the integrated busbar with integrated temperature control function realizes the integration of heating, heat dissipation, and information acquisition functions. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the structure of an integrated busbar with integrated temperature control function according to the present invention.

[0018] Figure 2 for Figure 1 A magnified diagram of point A in the middle.

[0019] Figure 3 for Figure 1 The diagram shown omits the busbar assembly in the plastic support structure.

[0020] Figure 4 for Figure 3 A magnified diagram of point B in the middle.

[0021] Figure 5 for Figure 3 The diagram shows the internal liquid cooling channels of the plastic support shown.

[0022] Figure 6 for Figure 2 The diagram shows a partial cross-sectional view of the plastic support and the battery cell in conjunction.

[0023] Figure 7 for Figure 1The diagram shows a series conductive busbar.

[0024] Figure 8 This is a manufacturing process flow diagram of an integrated busbar with integrated temperature control function according to the present invention.

[0025] The attached diagram lists the components represented by each number as follows: 10. Plastic bracket; 11. Support bridge; 12. First liquid cooling channel; 121. Heat-conducting section; 122. Connecting section; 13. Second liquid cooling channel; 14. First liquid inlet; 15. First liquid outlet; 16. Clearance hole; 20. Busbar assembly; 21. Series conductive busbar; 211. Bending part; 212. Welding part; 22. Output electrode conductive busbar; 30. FPC assembly; 31. FPC acquisition board; 311. Signal acquisition branch; 312. Connecting piece; 40. Connector; 50. Battery cell. Detailed Implementation

[0026] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are merely some, not all, of the embodiments of the present invention. Based on the description of the present invention, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of the present invention.

[0027] Unless otherwise explicitly specified and limited, the terms "setup," "installation," and "connection" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium. Those skilled in the art can understand the specific meaning of these terms based on the specific circumstances.

[0028] The terms “upper,” “lower,” “left,” “right,” “front,” “back,” “top,” “bottom,” “inner,” and “outer,” etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use. They are only for the convenience of description and simplification, 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 the present invention.

[0029] The terms “first,” “second,” “third,” etc., are used merely to distinguish elements with similar properties, not to indicate or imply relative importance or a specific order.

[0030] The terms “include,” “comprising,” or any other variation thereof are intended to cover non-exclusive inclusion, which includes not only the elements listed but also other elements not expressly listed.

[0031] Please see Figures 1-4 and Figure 6 An integrated busbar with integrated temperature control function includes a plastic bracket 10, a busbar assembly 20, and an FPC assembly 30. The busbar assembly 20 includes a series conductive bus 21 and an output conductive bus 22. The series conductive bus 21 and the output conductive bus 22 are respectively embedded in the plastic bracket 10. The FPC assembly 30 is disposed on the surface of the plastic bracket 10 and is electrically connected to the series conductive bus 21 and the output conductive bus 22.

[0032] More specifically, the FPC assembly 30 includes an FPC acquisition board 31 and a temperature sensor. The FPC acquisition board 31 has multiple signal acquisition branches 311, which are electrically connected to each series busbar 21 and each output busbar 22 via connecting pieces 312. The temperature sensor is mounted on the FPC acquisition board 31 and is used to monitor the temperature inside the battery pack. In this embodiment, the temperature sensor is an NTC sensor. An NTC sensor is a component that measures temperature by utilizing the characteristic that the resistance value decreases significantly with increasing temperature. It has the advantages of high sensitivity, fast response, low cost, and small size, making it very suitable for monitoring temperature changes inside the battery pack. In addition, one end of the FPC acquisition board 31 is electrically connected to a connector 40, so the FPC acquisition board 31 can transmit the voltage data of each cell 50 and the temperature data inside the battery pack to the BMS (Battery Management System) in real time, thereby realizing the signal acquisition and transmission function of the integrated busbar with integrated temperature control function.

[0033] The series conductive bus 21 is located on both sides of the plastic bracket 10 along its width direction, and the series conductive bus 21 is exposed on the upper and lower surfaces of the plastic bracket 10. The series conductive bus 21 is also welded to the terminals of two adjacent battery cells 50. The bus assembly 20 includes two output conductive buses 22, which are located at both ends of the plastic bracket 10 along its length direction and are electrically connected to external circuits.

[0034] The plastic bracket 10 is provided with a support bridge 11 for supporting the series conductive bus 21, and at least a portion of the series conductive bus 21 is in close contact with the upper surface of the support bridge 11.

[0035] The plastic bracket 10 has a first liquid cooling channel 12 inside. The first liquid cooling channel 12 is arranged around the periphery of the series conductive busbar 21 and passes through the interior of the support bridge 11.

[0036] The first liquid cooling channel 12 is filled with a coolant for heat conduction with the series conductive busbar 21, wherein the coolant is a 50% ethylene glycol aqueous solution.

[0037] When the battery pack is charging and discharging, the cell 50 releases a large amount of heat. Since the series conductive bus 21 is welded to the terminal of the cell 50, the heat inside the cell 50 is conducted to the series conductive bus 21. The temperature of the series conductive bus 21 rises sharply with the increase of the charging rate. Since the first liquid cooling channel 12 passes through the support bridge 11 that is in close contact with the series conductive bus 21 and is arranged at least around the periphery of the series conductive bus 21, the coolant in the first liquid cooling channel 12 can quickly carry away the heat of the series conductive bus 21, thereby reducing the temperature of the cell 50 and keeping the temperature of the cell 50 within the normal range, so as to ensure that the battery pack is always kept in the optimal operating temperature range.

[0038] When the battery pack is in a low-temperature environment, the coolant is heated by an external heat pump. The coolant can quickly heat the series conductive bus 21. Since the series conductive bus 21 is welded to the terminal of the cell 50, the heat of the series conductive bus 21 can be quickly conducted to the inside of the cell 50 through the terminal, so that the temperature of the cell 50 is maintained within the normal range, thus ensuring that the battery pack is always kept in the optimal operating temperature range.

[0039] As described above, the integrated busbar with integrated temperature control function provided by the present invention integrates the functions of heating, heat dissipation, and information acquisition by opening a first liquid cooling channel 12 inside the plastic bracket 10 and combining the first liquid cooling channel 12 with the support bridge 11, and embedding the busbar assembly 20 inside the plastic bracket 10. The liquid cooling plate, plastic bracket 10, and busbar assembly 20 are integrated into one, making the structure of the integrated busbar with integrated temperature control function compact, significantly reducing the number of parts, simplifying the assembly process of the battery module, effectively reducing the overall volume and weight of the battery pack, increasing the energy density of the battery pack, improving the assembly efficiency of the battery pack, and reducing the production cost of the battery pack. Through the cooperation of the plastic bracket 10, coolant, busbar assembly 20, and FPC assembly 30, the integrated busbar with integrated temperature control function realizes the integration of heating function, heat dissipation function, and information acquisition function.

[0040] Furthermore, in this embodiment, the series busbar 21 and the output busbar 22 are respectively embedded in the plastic bracket 10 through a coating process, thereby realizing that the busbar assembly 20 and the plastic bracket 10 form a single integral component.

[0041] It should be noted that the injection molding process refers to first placing a pre-made part (called an insert) into the mold, then closing the mold, and injecting molten plastic into the cavity. The molten plastic will flow and surround a specific part of the insert. After cooling, the insert and the plastic will be firmly bonded together to form an inseparable integrated component.

[0042] By using an injection molding process to encapsulate the busbars onto the plastic bracket 10, the busbar assembly 20 and the plastic bracket 10 can be highly integrated and unified, further improving the connection stability between the busbar assembly 20 and the plastic bracket 10. This also improves the insulation reliability of the plastic bracket 10. In addition, it can eliminate the subsequent assembly process of the busbar assembly 20 and the plastic bracket 10, thereby improving the assembly efficiency of the battery pack.

[0043] Furthermore, in this embodiment, the first liquid cooling channel 12 is manufactured by gas-assisted injection molding, thereby integrating the first liquid cooling channel 12 into the plastic bracket 10.

[0044] It should be noted that gas-assisted injection molding is an advanced injection molding technology. Its core principle is: in the traditional injection molding process, high-pressure inert gas (usually nitrogen) is injected into the molten plastic in the mold cavity. The gas is used to push and fill the space formed by the molten plastic in the mold cavity, and form a hollow channel.

[0045] The first liquid cooling channel 12, which is processed by gas-assisted injection molding, has a smooth inner wall, which helps to reduce the flow resistance of the coolant in the first liquid cooling channel 12; and it also makes the wall thickness of the first liquid cooling channel 12 uniform, which helps to improve the sealing reliability of the first liquid cooling channel 12 to prevent coolant leakage.

[0046] Please see Figure 5 The first liquid cooling channel 12 has two heat-conducting sections 121 and a connecting section 122 connecting the two heat-conducting sections 121. The two heat-conducting sections 121 are located on both sides of the plastic bracket 10 along the width direction. The heat-conducting sections 121 are arranged around the periphery of the series conductive busbar 21 at least, and the heat-conducting sections 121 pass through the interior of the support bridge 11.

[0047] Furthermore, in this embodiment, the heat-conducting section 121 is in the form of a continuous S-shape. By setting the heat-conducting section 121 to a continuous S-shape, on the one hand, the continuous S-shape can adapt well to the layout of the series conductive busbar 21, ensuring that the heat-conducting section 121 passes through the interior of the support bridge 11, and also allowing the heat-conducting section 121 to uniformly cover a portion of the periphery of the series conductive busbar 21, which helps to reduce heat exchange dead zones and thus improve the temperature uniformity within the battery pack; on the other hand, the continuous S-shape can extend the length of the heat-conducting section 121, increasing its heat exchange area and time with the series conductive busbar 21, thereby improving the heat exchange efficiency of the first liquid cooling channel 12.

[0048] Please see Figure 1The plastic support 10 is provided with a first liquid inlet 14 and a first liquid outlet 15, which are respectively connected to the ends of the two heat-conducting sections 121. The first liquid inlet 14 and the first liquid outlet 15 are located on the same side along the length of the plastic support 10. This arrangement can reduce the length and complexity of the external pipelines connected to the first liquid inlet 14 and the first liquid outlet 15, making the battery pack structure more compact. In addition, the fact that the first liquid inlet 14 and the first liquid outlet 15 are located on the same side can promote the formation of a longer flow path in the first liquid cooling channel 12, which helps to reduce the temperature difference between different areas of the plastic support 10.

[0049] Please see Figure 4 , Figure 6 and Figure 7 The series-connected busbar 21 has two welded portions 212 that are welded to the terminals of the battery cell 50 and a bent portion 211 that connects the two welded portions 212. The upper surface of the support bridge 11 is a smooth curved surface, and the lower surface of the bent portion 211 is in close contact with the upper surface of the support bridge 11. Since the heat-conducting section 121 of the first liquid cooling channel 12 passes through the interior of the support bridge 11, the close contact between the bent portion 211 and the upper surface of the support bridge 11 helps to reduce the thermal resistance between the coolant and the series-connected busbar 21. In addition, by setting the upper surface of the support bridge 11 to a smooth curved surface, the heat exchange area between the coolant and the series-connected busbar 21 can be increased, thereby improving the heat exchange efficiency between the coolant and the series-connected busbar 21.

[0050] Furthermore, the series conductive bus 21 is made of O-temper 1-series aluminum. It should be noted that O-temper 1-series aluminum is characterized by its softness, excellent ductility, and superior conductivity. The use of O-temper 1-series aluminum for the series conductive bus 21 ensures its conductivity; moreover, its softness and excellent ductility allow it to better conform to the upper surface of the support bridge 11, which helps reduce the thermal resistance between the coolant and the series conductive bus 21, thereby improving the heat exchange efficiency between the coolant and the series conductive bus 21.

[0051] Please see Figure 3 and Figure 5 The plastic bracket 10 has a second liquid cooling channel 13 inside, which is located below the FPC component 30 and between the two heat-conducting sections 121. The second liquid cooling channel 13 can perform precise heat exchange for the FPC component 30, greatly improving the temperature uniformity of the FPC acquisition board 31 surface, avoiding localized overheating, and helping to ensure the stability of the FPC component 30 operation.

[0052] Furthermore, in this embodiment, the second liquid cooling channel 13 is connected to the first liquid cooling channel 12, and the first liquid cooling channel 12 and the second liquid cooling channel 13 share the same coolant, first inlet 14, and first outlet 15.

[0053] In another embodiment, the second liquid cooling channel 13 is independent of the first liquid cooling channel 12. The plastic bracket 10 is provided with a second liquid inlet and a second liquid outlet, which are respectively connected to the second liquid cooling channel 13. The second liquid cooling channel 13 is filled with coolant for heat conduction with the FPC component 30.

[0054] For more details, please see Figure 3 The plastic bracket 10 has a relief hole 16 for avoiding the pressure relief valve of the battery cell 50.

[0055] Please see Figure 8 To better understand the technical solution of the present invention, the manufacturing process of the integrated busbar with integrated temperature control function of the present invention will be described below: (1) FPC component preparation: Cut the substrate material and sequentially perform the following processes on the substrate material: dry film / printing dry film, etching, micro-etching for cleaning, copper plating, reinforcement, lamination, baking and curing, OSP, solder paste printing, SMT placement, UV adhesive application, and UV curing to prepare FPC component 30.

[0056] (2) Plastic bracket preparation: A plastic bracket 10 with embedded conductive busbars and integrated liquid cooling channels is prepared by encapsulation process and gas-assisted injection molding process; wherein, the material of the plastic bracket 10 can be PPS (polyphenylene sulfide) or PPO (polyphenylene sulfide).

[0057] (3) Assemble the FPC component and plastic bracket: Fix the FPC component 30 to the plastic bracket 10 by hot riveting, and then weld the signal acquisition branch 311 of the FPC to the busbar by laser welding or ultrasonic welding process; if ultrasonic welding process is used, the weld point between the signal acquisition branch 311 and the busbar needs to be coated with UV glue.

[0058] (4) Testing and packaging: The integrated busbar with integrated temperature control function is subjected to EOL electrical testing, AVI visual inspection, and full inspection before being packaged.

[0059] In addition, the present invention also provides a battery pack including an integrated busbar with integrated temperature control function in any of the above embodiments.

[0060] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention 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 the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. An integrated busbar with integrated temperature control function, characterized in that, The device includes a plastic support (10), a bus assembly (20), and an FPC assembly (30). The bus assembly (20) includes a series bus (21) and an output bus (22). The series bus (21) and the output bus (22) are respectively embedded in the plastic support (10). The FPC assembly (30) is disposed on the surface of the plastic support (10) and is electrically connected to the series bus (21) and the output bus (22). The series conductive bus (21) is located on both sides of the plastic bracket (10) along the width direction, and the series conductive bus (21) is exposed on the upper and lower surfaces of the plastic bracket (10). The series conductive bus (21) is simultaneously welded to the poles of two adjacent cells (50). The plastic bracket (10) is provided with a support bridge (11) for supporting the series conductive bus (21). At least a portion of the series conductive bus (21) is in close contact with the upper surface of the support bridge (11). The plastic bracket (10) has a first liquid cooling channel (12) inside. The first liquid cooling channel (12) is arranged around the periphery of the series conductive bus (21) and passes through the interior of the support bridge (11). The first liquid cooling channel (12) is filled with coolant for heat conduction with the series conductive bus (21).

2. The integrated busbar with integrated temperature control function as described in claim 1, characterized in that, The first liquid cooling channel (12) is manufactured by gas-assisted injection molding process.

3. The integrated busbar with integrated temperature control function as described in claim 1, characterized in that, The first liquid cooling channel (12) has two heat-conducting sections (121) and a connecting section (122) connecting the two heat-conducting sections (121). The two heat-conducting sections (121) are located on both sides of the plastic bracket (10) along the width direction. The heat-conducting sections (121) are arranged around the periphery of the series conductive bus (21) at least, and the heat-conducting sections (121) pass through the interior of the support bridge (11).

4. The integrated busbar with integrated temperature control function as described in claim 3, characterized in that, The heat-conducting section (121) is in a continuous S-shape.

5. The integrated busbar with integrated temperature control function as described in claim 3, characterized in that, The plastic bracket (10) is provided with a first liquid inlet (14) and a first liquid outlet (15), and the first liquid inlet (14) and the first liquid outlet (15) are respectively connected to the ends of the two heat-conducting sections (121).

6. The integrated busbar with integrated temperature control function as described in claim 1, characterized in that, The series conductive bus (21) has two welded parts (212) that are welded to the poles of the battery cell (50) and a bent part (211) that connects the two welded parts (212). The upper surface of the support bridge (11) is a smooth curved surface, and the lower surface of the bent part (211) is in close contact with the upper surface of the support bridge (11).

7. The integrated busbar with integrated temperature control function as described in claim 1, characterized in that, The series conductive bus (21) is made of O-state 1 series aluminum.

8. The integrated busbar with integrated temperature control function as described in claim 1, characterized in that, The plastic bracket (10) has a second liquid cooling channel (13) inside, and the second liquid cooling channel (13) is located below the FPC assembly (30).

9. The integrated busbar with integrated temperature control function as described in claim 8, characterized in that, The second liquid cooling channel (13) is connected to the first liquid cooling channel (12).

10. A battery pack, characterized in that, The integrated busbar includes the integrated temperature control function as described in any one of claims 1 to 9.

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