Traction battery cooling system, battery pack, and vehicle

Abstract

Disclosed in the present disclosure are a traction battery cooling system, a battery pack, and a vehicle. The traction battery cooling system comprises a first cooling subsystem, a second cooling subsystem and a lines group, wherein the first cooling subsystem comprises a first flow distribution channel, a first coolant intake port and a first coolant return port; the first coolant intake port is in communication with an inlet of the first flow distribution channel, and the first coolant return port is in communication with an outlet of the first flow distribution channel; the second cooling subsystem comprises a second flow distribution channel, a main distribution area, a main return area, a second coolant intake port, a second coolant return port, a third coolant intake port and a third coolant return port; the main distribution area is in communication with an inlet of the second flow distribution channel, and the main return area is in communication with an outlet of the second flow distribution channel; and the second coolant intake port and the third coolant intake port are both in communication with the main distribution area, and the second coolant return port and the third coolant return port are both in communication with the main return area. In this way, the uniformity of coolant flow distribution at the bottom and top is effectively improved, while ensuring high heat dissipation efficiency.

Description

Power battery cooling system, battery pack and vehicle

[0001] Cross-reference to related applications

[0002] This disclosure is based on and claims priority to Chinese Patent Application No. 202411909396.1, filed on December 23, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to the field of automotive technology, specifically to a power battery cooling system, a battery pack, and a vehicle. Background Technology

[0004] Typically, battery packs provide power to electric devices. Taking electric vehicles as an example, a battery pack consists of a certain number of cells arranged in a specific pattern. For the cells assembled in the battery pack, good heat dissipation is required to achieve reliable and stable thermal management, thereby ensuring the performance, stability, and lifespan of the entire battery pack. A typical solution is to configure cooling systems at both the bottom and top of the battery pack. These bottom and top cooling systems are usually connected in series or parallel within a liquid cooling system. For series cooling schemes, the system flow resistance is relatively high, affecting the system's heat dissipation efficiency; for parallel cooling schemes, the distribution piping is more complex, leading to uneven flow distribution.

[0005] In view of this, there is an urgent need to provide solutions for cooling existing battery packs to overcome the aforementioned shortcomings. Summary of the Invention

[0006] To address the aforementioned technical issues, this disclosure provides a power battery cooling system, a battery pack, and a vehicle. Through system optimization of the battery pack cooling scheme, the uniformity of liquid cooling flow distribution at the bottom and top is effectively improved while ensuring good heat dissipation efficiency.

[0007] The first aspect of this disclosure provides a power battery cooling system, which includes a first cooling subsystem, a second cooling subsystem, and a piping assembly. The first and second cooling subsystems each have a heat exchange area, with one subsystem positioned at the top of the battery pack and the other at the bottom. The first cooling subsystem includes a first branch channel, a first liquid inlet, and a first liquid return port. The first liquid inlet is connected to the inlet of the first branch channel, and the first liquid return port is connected to the outlet of the first branch channel. The second cooling subsystem includes a second branch channel, a main branch area, a main return area, a second liquid inlet, a second liquid return port, a third liquid inlet, and a third liquid return port. The main branch area is connected to the inlet of the second branch channel, and the main return area is connected to the outlet of the second branch channel. The second and third liquid inlets are respectively connected to the main branch area, and the second and third liquid return ports are respectively connected to the main return area. The third liquid inlet and the first liquid inlet, as well as the first and third liquid return ports, are respectively connected via the piping assembly. With this configuration, the two subsystems (the first cooling subsystem and the second cooling subsystem) used for top and bottom cooling heat dissipation are coupled in series and parallel. Based on the total distribution area configured on the side of the second cooling subsystem (bottom cold plate), it can achieve uniform flow distribution in its own second distribution channel and also achieve uniform flow distribution to the first distribution channel on the side of the first cooling subsystem (top cooling system). At the same time, based on the total return area configured on the side of the second cooling subsystem, it can achieve return flow in its own second distribution channel and also achieve return flow in the first distribution channel on the side of the first cooling subsystem. The two subsystems can obtain a relatively uniform distribution of coolant flow within the heat exchange area, thereby ensuring good heat dissipation efficiency.

[0008] In some embodiments, the piping assembly is located on the same end side as the first liquid inlet and first liquid return interface of the first cooling subsystem, and the second liquid inlet, second liquid return interface, third liquid inlet, and third liquid return interface of the second cooling subsystem. This arrangement of the piping assembly on the same end side as the interfaces of the first and second cooling subsystems—for example, but not limited to, the piping assembly can be positioned above the main distribution area and the main return area of ​​the first cooling subsystem—effectively improves integration and further mitigates the adverse effects of complex branch piping on flow resistance. Furthermore, the use of a piping assembly located on the same end side as the main distribution area and the main return area effectively reduces the flow resistance of the entire power battery cooling system, further improving heat dissipation efficiency.

[0009] In some embodiments, the first cooling subsystem includes multiple sets of cold plate assemblies, with a first flow channel formed inside each cold plate assembly, and a first liquid inlet and a first liquid return interface provided on each cold plate assembly; the cold plate assemblies are arranged sequentially along a second direction to form the heat exchange area of ​​the first cooling subsystem. In some embodiments, the number of cold plate assemblies can be selected as needed, for example, but not limited to two or more, which can improve the uniformity of flow distribution among the cold plate assemblies.

[0010] In some embodiments, the cold plate assembly includes a first current collector, a second current collector, a shunt harmonica tube, and a return harmonica tube. One end of the shunt harmonica tube and the return harmonica tube are inserted into the first current collector, and the other end is inserted into the second current collector. The tube bodies of the shunt harmonica tube and the return harmonica tube extend along a first direction and are spaced apart in a second direction. A first liquid inlet and a first liquid return outlet are disposed on the first current collector. The first direction and the second direction are two directions within the cell arrangement plane. In practical applications, the first current collector may include a first cavity and a second cavity separated from each other. The first liquid inlet and the shunt harmonica tube communicate with the first cavity of the first current collector, and the first liquid return outlet and the return harmonica tube communicate with the second cavity of the first current collector. In this way, the low-temperature coolant can enter the first chamber of the first collector through the first inlet port and flow into the distribution harmonica tube. After reaching the second collector, it flows back to the second chamber of the first collector through the return harmonica tube. The high-temperature coolant that has completed heat exchange flows out through the first return port, which can further improve the uniformity of distribution.

[0011] In some embodiments, the first collector has two first cavities, which are respectively located on both sides of the second cavity of the first collector. Overall, while achieving good flow distribution uniformity, the flow resistance within the cold plate assembly can be further rationally controlled.

[0012] In some embodiments, the second collector includes a first chamber and a second chamber that are separated from each other, and a plurality of both the diversion harmonica tubes and the return harmonica tubes. In a second direction, a portion of the plurality of diversion harmonica tubes and the plurality of return harmonica tubes communicate with the first chamber of the second collector, and another portion communicates with the second chamber of the second collector. This avoids turbulence that could affect the flow of coolant within the second collector, thereby improving heat exchange efficiency.

[0013] In some embodiments, the second cooling subsystem includes a flow channel plate and a heat exchange plate. The flow channel plate has grooves corresponding to the second branch flow channel, the main branch area, and the main return area, respectively. The heat exchange plate is stacked on the surface of the grooves on the flow channel plate, enclosing the second branch flow channel, the main branch area, and the main return area. A second liquid inlet, a second liquid return, a third liquid inlet, and a third liquid return are disposed on the heat exchange plate, and the heat exchange plate forms the heat exchange area of ​​the second cooling subsystem. It features a simple and compact structure and excellent temperature uniformity.

[0014] In practical applications, the number of the third liquid inlet and the third liquid return are the same as the number of the cold plate assemblies in the first cooling subsystem.

[0015] In some embodiments, in the first direction, the main distribution area is located close to the second branch channel, and the main return area is located on the side of the main distribution area away from the second branch channel. This arrangement makes full use of the available space and has good integration.

[0016] In some embodiments, the second flow channel includes multiple sub-flow channels. In the second direction, the upstream flow channel section with inlet of each sub-flow channel is located in the middle region of the heat dissipation area, and the downstream flow channel section with outlet of each sub-flow channel is located on both sides of the heat dissipation area. In this way, the low-temperature coolant entering each sub-flow channel through the inlet first cools the cells located in the middle with relatively poor heat dissipation conditions, and then cools the cells located on the sides, thus preventing thermal runaway. Overall, the temperature of each cell tends to be more uniform.

[0017] In some embodiments, in the second direction, the inlet of each sub-channel of the second branch channel may be located in the middle, and correspondingly, the outlet of each sub-channel of the second branch channel is located on both sides of the inlet, and the total return region surrounds the two ends of the total branch region in the second direction to communicate with each outlet of the second branch channel respectively.

[0018] In some embodiments, the piping assembly further includes a first pipe, a second pipe, a third pipe, and a fourth pipe. One end of the first pipe is connected to the second liquid inlet port, and the other end is used to connect to the output pipe of the system's liquid cooling circuit. One end of the second pipe is connected to the second liquid return port, and the other end is used to connect to the recovery pipe of the system's liquid cooling circuit. The third pipe is connected between the third liquid inlet port and the first liquid inlet port, and the fourth pipe is connected between the first liquid return port and the third liquid return port. This forms a piping assembly with external connections, providing good operability.

[0019] In some embodiments, in a first direction, the piping group is located on the same end side as the first liquid inlet and first liquid return interface of the first cooling subsystem, and the second liquid inlet, second liquid return interface, third liquid inlet and third liquid return interface of the second cooling subsystem.

[0020] A second aspect of this disclosure provides a battery pack comprising a plurality of sequentially arranged battery cells and a power battery cooling system as described above.

[0021] A third aspect of this disclosure provides a vehicle including a battery pack employing the battery pack described above. Attached Figure Description

[0022] Figure 1 is a schematic diagram of the overall structure of a battery pack provided in an embodiment of this disclosure;

[0023] Figure 2 is an exploded view of the assembly of the power battery cooling system shown in Figure 1.

[0024] Figure 3 is an axial view of a cold plate assembly of a first cooling subsystem provided in an embodiment of this disclosure;

[0025] Figure 4 is an exploded view of the assembly of a second cooling subsystem provided in an embodiment of this disclosure;

[0026] Figure 5 is a front view of the heat spreader shown in Figure 4;

[0027] Figure 6 is a front view of the flow channel plate shown in Figure 4;

[0028] Figure 7 is an isometric view of a pipeline assembly provided in an embodiment of this disclosure;

[0029] Figure 8 is a cross-sectional view of AA in Figure 3;

[0030] Figure 9 is a cross-sectional view of BB in Figure 3;

[0031] Figure 10 is an exploded view of the assembly of a first pipeline provided in an embodiment of this disclosure;

[0032] Figure 11 is an exploded view of the assembly of a second pipeline provided in an embodiment of this disclosure;

[0033] Figure 12 is an isometric view of a flange provided in an embodiment of this disclosure;

[0034] Figure 13 is a schematic diagram of the assembly relationship between the flange and the battery pack shown in Figure 12;

[0035] Figure 14 is an exploded view of the assembly of a third pipeline provided in an embodiment of this disclosure;

[0036] Figure 15 is an exploded view of the assembly of a fourth pipeline provided in an embodiment of this disclosure.

[0037] Reference numerals: 100, Battery pack; 10, Cooling system; 20, Housing frame; 30, Protective plate; 1, First cooling subsystem; 11, First distribution channel; 111, First collector; 1111, First sealing plate; 112, Second collector; 1121, Second sealing plate; 113, Distribution harmonica tube; 114, Return harmonica tube; 12, First liquid inlet; 13, First liquid return; 2, Second cooling subsystem; 211, Flow channel plate; 212, Heat spreader plate; 21, Second distribution channel; 22, Main distribution area; 23, Main return area; 25, Second liquid inlet; 26, Second liquid return; 27, Third liquid inlet; 28, Third liquid return; 29, Reinforcing groove; 210, Reinforcing rib; 3. Piping Assembly; 31. First Pipe; 311. First Pipe First Female Connector; 312. First Pipe Connecting Pipe; 313. First Pipe Second Female Connector; 314. First Pipe Fireproof Sheath; 32. Second Pipe; 321. Second Pipe First Female Connector; 322. Second Pipe Connecting Pipe; 323. Second Pipe Second Female Connector; 324. Second Pipe Fireproof Sheath; 33. Third Pipe; 331. Third Pipe First Female Connector; 332. Third Pipe Connecting pipe; 333, Second female plug of the third pipe; 334, Fireproof sleeve of the third pipe; 34, Fourth pipe; 341, First female plug of the fourth pipe; 342, Connecting pipe of the fourth pipe; 343, Second female plug of the fourth pipe; 344, Fireproof sleeve of the fourth pipe; 35, Flange; 351, Flange face; 352, Flange faucet; 353, Male connector of the flange pipe; 354, Flange sealing ring; 355, Bolt mounting hole; 356, Bolt. Detailed Implementation

[0038] To enable those skilled in the art to better understand the technical solutions of this disclosure, the disclosure will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0039] Please refer to Figures 1 and 2, wherein Figure 1 is a schematic diagram of the overall structure of a battery pack provided in an embodiment of this disclosure, and Figure 2 is an exploded view of the assembly of the power battery cooling system shown in Figure 1.

[0040] The battery pack 100 provided in this embodiment includes a plurality of battery cells (not shown in the figure) and a cooling system 10 arranged sequentially within the casing frame 20. In specific implementations, the battery cells can be square or cylindrical, and this embodiment does not limit the specific implementation. For ease of description, two directions are defined in the plane in which the multiple battery cells are arranged: a first direction X and a second direction Y, and a direction perpendicular to the plane in which the battery cells are arranged is defined as a third direction Z, which is also the vertical direction of the battery pack 100 in the illustrated state.

[0041] Figure 1 shows a schematic diagram of one usage state of the battery pack. The second cooling subsystem 2 of the cooling system 10 is located at the top, that is, on the side where the battery pack 100 is mounted on the vehicle chassis; the first cooling subsystem 1 is fitted with the protective plate 30, which provides protection based on the protective plate 30 located at the bottom of the battery pack. In this state, the battery cells are inverted.

[0042] In other possible implementations, the second cooling subsystem 2 can also be fitted to the protective plate 30, while the first cooling subsystem 1 is adjacent to the battery cover. In this state, the battery cell is in an upright position.

[0043] Referring to Figure 2, the cooling system includes a first cooling subsystem 1, a second cooling subsystem 2, and a piping assembly 3. The first cooling subsystem 1 and the second cooling subsystem 2 each have a heat exchange surface. One of the first cooling subsystem 1 and the second cooling subsystem 2 is located at the top of the battery pack 100, and the other is located at the bottom of the battery pack 100. Here, "heat exchange surface" refers to a surface extending along the plane of the battery cell arrangement for cooling and heat exchange on the cell side. This "heat exchange surface" includes the case of a continuous heat exchange surface, and also includes the case of a multiple heat exchange surfaces spaced apart. Here, "top" refers to the side of the battery pack 100 where the battery cell terminals are located, and "bottom" refers to the side of the battery pack 100 opposite to the battery cell terminals. In some embodiments, as shown in FIG2, a first cooling subsystem 1 may be disposed on the top of the battery pack 100, and its heat exchange area includes a plurality of heat exchange surfaces spaced apart by each bellows tube, for cooling the terminal posts at the top of each battery cell; a second cooling subsystem 2 may be disposed on the bottom of the battery pack 100, and its heat exchange area is a continuous heat exchange surface provided by a heat spreader, for cooling the bottom of each battery cell. It should be understood that in other specific implementations, the first cooling subsystem 1 and the second cooling subsystem 2 may also be disposed in opposite directions relative to the battery cells, that is, the first cooling subsystem 1 is disposed on the bottom of the battery pack 100 and the second cooling subsystem 2 is disposed on the top of the battery pack 100, and can also cool and dissipate heat to the battery cells on the corresponding side through their respective heat exchange areas. This disclosure does not limit the scope of the embodiments.

[0044] The first cooling subsystem 1 includes multiple first branch channels 11, a first liquid inlet 12, and a first liquid return 13. Please also refer to Figure 3, which is an isometric schematic diagram of a first cooling subsystem provided in an embodiment of this disclosure.

[0045] Multiple first distribution channels 11 are arranged within the heat exchange area, and the multiple first distribution channels 11 can provide a relatively uniform coolant flow rate to the top of each cell. In the first direction X, the first liquid inlet 12 and the first liquid return 13 are located at one end of the first distribution channel 11, wherein the first liquid inlet 12 is connected to the inlet of the first distribution channel 11, and the first liquid return 13 is connected to the outlet of the first distribution channel 11.

[0046] The second cooling subsystem 2 includes multiple second branch channels 21, a main branch area 22, a main return area 23, a second liquid inlet 25, a second liquid return interface 26, a third liquid inlet 27, and a third liquid return interface 28. Please refer to Figures 4, 5, and 6 together. Figure 4 is an exploded view of the assembly of a second cooling subsystem provided in an embodiment of this disclosure. Figure 5 is a front view of the heat spreader plate shown in Figure 4, and Figure 6 is a front view of the flow channel plate shown in Figure 4.

[0047] Multiple second distribution channels 21 are arranged within the heat exchange area, providing a relatively uniform coolant flow rate to the bottom of each cell. In the first direction X, the main distribution area 22 and the main return area 23 are located at one end of the second distribution channels 21. The main distribution area 22 is connected to the inlet of the multiple second distribution channels 21, so that the low-temperature coolant flowing into the main distribution area 22 flows to the multiple second distribution channels 21; the main return area 23 is connected to the outlet of the multiple second distribution channels 21, so that the high-temperature coolant that has completed heat exchange with the cell side flows back to the main return area 23. The second liquid inlet 25 and the third liquid inlet 27 are respectively connected to the main distribution area 22, and the second liquid return 26 and the third liquid return 28 are respectively connected to the main return area 23.

[0048] In other possible implementations, the number of first distribution channels 11 on the first cooling subsystem 1 side and second distribution channels 21 on the second cooling subsystem 2 side can be determined according to the overall product design requirements. For example, one first distribution channel 11 can be provided on the first cooling subsystem 1 side to dissipate heat from the top of each cell; and one second distribution channel 21 can be provided on the second cooling subsystem 2 side to dissipate heat from the bottom of each cell. This disclosure does not limit the scope of the embodiments.

[0049] The pipeline assembly 3 includes a first pipeline 31, a second pipeline 32, a third pipeline 33, and a fourth pipeline 34. Please refer to Figures 2 and 7, where Figure 7 is an isometric view of a pipeline assembly provided in an embodiment of this disclosure. In the first direction X, the pipeline assembly 3 is located on the same end as the first liquid inlet 12 and the first liquid return 13 of the first cooling subsystem 1, and the second liquid inlet 25, the second liquid return 26, the third liquid inlet 27, and the third liquid return 28 of the second cooling subsystem 2.

[0050] One end of the first pipe 31 is connected to the second liquid inlet 25 of the second cooling subsystem 2, and the other end is used to connect to the coolant output pipe of the system liquid cooling circuit (not shown in the figure). The low-temperature coolant provided by the system liquid cooling circuit can be transported to the total distribution area 22 on the side of the second cooling subsystem 2 via the first pipe 31 and the second liquid inlet 25. One end of the second pipe 32 is connected to the second liquid return 26 of the second cooling subsystem 2, and the other end is used to connect to the coolant recovery pipe of the system liquid cooling circuit. The high-temperature coolant collected in the total return area 23 on the side of the second cooling subsystem 2 can be transported to the system liquid cooling circuit via the second liquid return 26 and the second pipe 32.

[0051] The third pipe 33 is connected between the third liquid inlet 27 of the second cooling subsystem 2 and the first liquid inlet 12 of the first cooling subsystem 1, and is used to transport the low-temperature coolant flowing into the main distribution area 22 of the second cooling subsystem 2 to the first cooling subsystem 1; that is, part of the low-temperature coolant flowing into the main distribution area 22 flows to the second branch channel 21 of the second cooling subsystem 2, and the other part flows to the first branch channel 11 of the first cooling subsystem 1.

[0052] The fourth pipe 34 is connected between the first return liquid interface 13 of the first cooling subsystem 1 and the third return liquid interface 28 of the second cooling subsystem 2. It is used to transport the high-temperature coolant that has completed heat exchange to the total return area 23 on the side of the second cooling subsystem 2. That is, it is combined with the high-temperature coolant flowing back from the second branch channel 21 in the total return area 23 and then transported to the system liquid cooling circuit.

[0053] With this configuration, the two subsystems (first cooling subsystem 1 and second cooling subsystem 2) used for top and bottom cooling heat dissipation are coupled in series and parallel. Based on the total distribution area 22 configured on the side of the second cooling subsystem 2 (bottom cold plate), it can achieve uniform flow distribution to each second branch channel 21 on its own side, and also achieve uniform flow distribution to each first branch channel 11 on the side of the first cooling subsystem 1 (top cooling system). At the same time, based on the total return area 23 configured on the side of the second cooling subsystem 2, it can achieve return flow to each second branch channel 21 on its own side, and also achieve return flow to each first branch channel 11 on the side of the first cooling subsystem 1. With the help of the pipe group 3 located on the same end side as the total distribution area 22 and the total return area 23, the flow resistance of the entire power battery cooling system can be effectively reduced, and the two subsystems can obtain a coolant flow rate that tends to be uniformly distributed within the heat exchange area.

[0054] In addition, in the power battery cooling system provided in this embodiment, the pipe assembly 3 and the interfaces (first liquid inlet interface 12, first liquid return interface 13, second liquid inlet interface 25, second liquid return interface 26, third liquid inlet interface 27 and third liquid return interface 28) of the first cooling subsystem 1 and the second cooling subsystem 2 are arranged on the same end side in the first direction X. For example, but not limited to, the pipe assembly 3 can be arranged above the total distribution area 22 and the total return area 23 of the second cooling subsystem 2, which can effectively improve the integration and further avoid the adverse effects of the complex shunt pipe on the flow resistance.

[0055] To better understand the technical solutions and effects of this disclosure, without loss of generality, the specific embodiments will be described in detail below with reference to the accompanying drawings.

[0056] Referring to Figures 2, 3, 8, and 9, where Figure 8 is a cross-sectional view AA in Figure 3 and Figure 9 is a cross-sectional view BB in Figure 3, in some embodiments, the first cooling subsystem 1 includes three sets of cold plate assemblies, with a first flow channel 11 formed inside the cold plate assemblies. Each cold plate assembly is sequentially arranged in the second direction Y, forming the heat exchange area of ​​the first cooling subsystem 1. In other specific implementations, the number of cold plate assemblies can be selected as needed, for example, but not limited to two or more others. This disclosure does not limit the scope of the embodiments.

[0057] As shown in Figure 3, the cold plate assembly is provided with a first inlet port 12 for coolant to flow in and a first return port 13 for coolant to flow out. These are connected to the second cooling subsystem 2 via corresponding third pipes 33 and fourth pipes 34, respectively, which improves the uniformity of coolant distribution among the cold plate assemblies. Here, the first inlet port 12 and the first return port 13 can be male connectors, and female connectors can be configured on the corresponding third pipes 33 and fourth pipes 34. The specific configuration can be determined as needed and will not be elaborated further here.

[0058] To further improve the uniformity of coolant distribution, the cold plate assembly includes a first current collector 111, a second current collector 112, multiple shunt harmonica tubes 113, and multiple return harmonica tubes 114. The tubes of the shunt harmonica tubes 113 and the return harmonica tubes 114 extend along the first direction X, and their total length can cover all the cells in the battery pack. One end of each harmonica tube is inserted into the first current collector 111, and the other end of each harmonica tube is inserted into the second current collector 112. The shunt harmonica tubes 113 and the return harmonica tubes 114 are arranged alternately in the second direction Y to achieve coolant distribution.

[0059] Each cold plate assembly has a first liquid inlet 12 and a first liquid return 13 disposed on a first collector 111. The first collector 111 includes a first cavity and a second cavity separated by a first sealing plate 1111. The first liquid inlet 12 communicates with the first cavity of the first collector 111, and the diversion harmonica tube 113 communicates with the first cavity. The first liquid return 13 communicates with the second cavity of the first collector 111, and the return harmonica tube 114 communicates with the second cavity. Low-temperature coolant can enter the first cavity of the first collector 111 through the first liquid inlet 12 and flow into the diversion harmonica tubes 113. After reaching the second collector 112, it flows back to the second cavity of the first collector 111 through the return harmonica tubes 114. The high-temperature coolant that has completed heat exchange flows out through the first liquid return 13.

[0060] In this embodiment, the first collector 111 includes two first chambers and one second chamber. Two first liquid inlet ports 12 are provided, each corresponding to one of the first chambers. The openings of the two first liquid inlet ports 12 face the second cooling subsystem 2 in the third direction Z, and the first liquid return port 13 faces outward in the first direction X, which has good assembly processability.

[0061] As shown in Figure 8, in the second direction Y, the second cavity is located in the middle, and the two first cavities are located on both sides of the second cavity, with adjacent cavities separated. Correspondingly, the return harmonica tube 114, which communicates with the second cavity of the first collector 111, is located in the middle, and the diversion harmonica tubes 113, which communicate with the first cavity of the first collector 111, are located on both sides of the return harmonica tube 114. Overall, while achieving good flow uniformity, the flow resistance within the cold plate assembly can be further rationally controlled.

[0062] In a specific implementation, the second collector 112 may also include a first cavity and a second cavity separated by a second sealing plate 1121, as shown in Figure 9. In the second direction Y, a portion of the plurality of branch harmonica tubes 113 and the plurality of return harmonica tubes 114 are connected to the first cavity of the second collector 112, and another portion of the plurality of branch harmonica tubes 113 and the plurality of return harmonica tubes 114 are connected to the second cavity of the second collector 112. In this way, turbulence that affects the flow of coolant can be avoided within the second collector 112.

[0063] In this embodiment, the cold plate assembly has two flow-diverting harmonica tubes 113 and two return harmonica tubes 114. However, in other specific implementations, the actual number of flow-diverting harmonica tubes 113 and 114 may be one, for example, but not limited to, one. This can be determined based on the overall product design requirements. This disclosure does not limit the scope of the embodiment.

[0064] In addition, for the diversion harmonica tube 113 and the return harmonica tube 114, the width of each harmonica tube can be 40mm to 60mm, the height can be 3mm to 5mm, and the distance between two adjacent harmonica tubes can be between 30mm and 100mm, so as to form a reliable smoke and exhaust channel.

[0065] In addition, the harmonica tubes can be made of plastic or aluminum alloy. In specific implementation, except for the first liquid inlet 12 and the two first liquid return 13, the other components can be coated with a fireproof and insulating coating, which can still maintain insulation performance after high-intensity flame impact, for example, 1000℃ flame impact for 15 minutes, DC 4000V, leakage current <1mA.

[0066] As shown in Figures 4, 5 and 6, the second cooling subsystem 2 includes a flow channel plate 211 and a heat exchange plate 212. The flow channel plate 211 has grooves that correspond to the second branch flow channel 21, the main branch area 22 and the main return area 23, respectively. The heat exchange plate 212 is stacked on the surface of the grooves on the flow channel plate 211, forming the second branch flow channel 21, the main branch area 22 and the main return area 23, respectively. The heat exchange area of ​​the second cooling subsystem 2 is formed by the heat exchange plate 212.

[0067] In this embodiment, the second liquid inlet 25, the second liquid return 26, the third liquid inlet 27, and the third liquid return 28 are disposed on the temperature distribution plate 212 and are connected to the main distribution area 22 and the main return area 23 respectively through through holes on the temperature distribution plate 212. The number of third liquid inlet ports 27 and third liquid return ports 28 is the same as that of the cold plate assembly, and they are arranged one-to-one, as shown in Figures 4 and 5. There are three third liquid inlet ports 27 and three third liquid return ports 28, which can be connected to the corresponding cold plate assemblies through the corresponding third pipe 33 and fourth pipe 34.

[0068] Similarly, the third liquid inlet port 27 and the third liquid return port 28 can be male connectors, and female connectors can be configured on the corresponding third pipeline 33 and fourth pipeline 34 sides, which can be determined according to needs. The second liquid inlet port 25 and the second liquid return port 26 can also be male connectors, and female connectors can be configured on the corresponding first pipeline 31 and second pipeline 32 sides.

[0069] As shown in Figure 6, in the first direction X, the main distribution area 22 is set close to the second branch channel 21, and the main return area 23 is located on the side of the main distribution area 22 away from the second branch channel 21, making full use of the available space and having a good degree of integration.

[0070] To further improve the uniformity of heat distribution, the second distribution channel 21 includes multiple sub-channels. In the second direction Y, the upstream channel section with an inlet is located in the middle region of the heat dissipation area, while the downstream channel section with an outlet is located on both sides of the heat dissipation area. In this way, the low-temperature coolant entering each sub-channel through the inlet first cools the cells in the middle where the heat dissipation conditions are relatively poor, and then cools the cells on the sides, thus preventing thermal runaway. Overall, the temperature of each cell tends to be more uniform.

[0071] In other words, in the second direction Y, the inlets of each sub-channel of the second branch channel 21 are located in the middle, and the outlets of each sub-channel of the second branch channel 21 are located on both sides of the inlet. Based on this, the total return region 23 surrounds both ends of the total branch region 22 to communicate with each outlet of the second branch channel 21 respectively.

[0072] In a specific implementation, each sub-channel can be arranged in a roundabout and tortuous manner, for example, but not limited to, using a 90° bending angle, so that the coolant flowing into each sub-channel of the second branch channel 21 can fully exchange heat with the cell side through the heat exchange plate 212.

[0073] Furthermore, to improve the load-bearing strength of the second cooling subsystem 2, reinforcing grooves 29 can be provided on the flow channel plate 211. In the second direction Y, the reinforcing grooves 29 are respectively provided on both sides of the second branch channel 21. These reinforcing grooves 29 can be manufactured using the same process as the second branch channel 21, and their shape is equivalent to a dummy flow channel with no coolant flowing inside. This effectively enhances the load-bearing strength of the plate.

[0074] In a specific implementation, the reinforcing groove 29 can also be set at a position within the plate surface where the second branch channel 21 is not provided. Simultaneously, reinforcing ribs 210 can be provided within the grooves of the main branch area 22 and the main return area 23 to further increase the local plate strength while satisfying the function of fluid interconnection.

[0075] As shown in Figure 7, the number of third pipes 33 and fourth pipes 34 in pipe group 3 is the same as the number of cold plate assemblies, and they are set one-to-one. In this embodiment, three third pipes 33 and three fourth pipes 34 are set to realize the connection between the main distribution area 22 and the main return area 23 on the side of the second cooling subsystem 2 and the cold plate assemblies on the side of the first cooling subsystem 1.

[0076] Referring to Figures 7 and 10, where Figure 10 is an exploded view of the assembly of a first pipeline according to an embodiment of this disclosure, the first pipeline 31 includes a first female connector 311, a first connecting pipe 312, and a second female connector 313. The two ends of the first connecting pipe 312 are connected to the first female connector 311 and the second female connector 313, respectively. The opening of the first female connector 311 can face the side opposite to the battery pack in the first direction X, for connection to the system liquid cooling circuit side. The opening of the second female connector 313 can face the second cooling subsystem 2 in the third direction Z, for connection to the second liquid inlet 25 on the side of the second cooling subsystem 2.

[0077] To facilitate assembly, the first pipe connection 312 is a flexible pipe, such as, but not limited to, a corrugated pipe or a flexible hose made of elastic material. Furthermore, the first pipe 31 may also include a first pipe fireproof sleeve 314 that wraps around the first pipe connection 312 to improve reliability. Additionally, an NTC can be installed on the second female connector 313 of the first pipe to detect the temperature of the coolant in the input pipe.

[0078] Referring to Figures 7 and 11, where Figure 11 is an exploded view of the assembly of a second pipeline according to an embodiment of this disclosure, the second pipeline 32 includes a first female connector 321, a connecting pipe 322, and a second female connector 323. The two ends of the connecting pipe 322 are connected to the first female connector 321 and the second female connector 323, respectively. The opening of the first female connector 321 can face the side opposite to the battery pack in the first direction X, for connection to the system liquid cooling circuit side. The opening of the second female connector 323 can face the second cooling subsystem 2 in the third direction Z, for connection to the second return interface 26 on the second cooling subsystem 2 side.

[0079] To facilitate assembly, the second pipe connection 322 is a flexible pipe, such as, but not limited to, a corrugated pipe or a flexible hose made of elastic material. Furthermore, the second pipe 32 may also include a fire-resistant sleeve 324 that wraps around the second pipe connection 322 to improve reliability. Additionally, an NTC can be installed on the second female connector 323 of the second pipe to detect the temperature of the coolant in the output pipe.

[0080] In a specific implementation, the first pipe 31 and the second pipe 32 can be connected to the liquid cooling circuit side of the system via a flange 35. Please refer to Figures 7 and 12 together, where Figure 12 is an isometric view of a flange provided in an embodiment of this disclosure. The flange 35 includes a flange face 351, a flange water nozzle 352, and a flange pipe male connector 353. In the first direction X, the flange water nozzle 352 and the flange pipe male connector 353 are respectively located on both sides of the flange face 351. The flange water nozzle 352 is used to connect to the coolant inlet and outlet pipes of the vehicle's system liquid cooling circuit. The first female connector 311 of the first pipe 31 and the first female connector 321 of the second pipe 32 are respectively connected to the corresponding flange pipe male connector 353.

[0081] The flange face 351 has a grooved structure for installing the flange sealing ring 354, and the flange face 351 also has bolt mounting holes 355; please refer to Figure 13, which is a schematic diagram of the assembly relationship between the flange and the battery pack shown in Figure 12. After assembly, most of the flange water nozzle 352 is located outside the battery pack for mating with the vehicle's inlet and outlet water pipes, and the remaining part is located inside the battery pack. The flange face 351 is tightly fitted to the inner wall of the battery pack housing frame, and is sealed by the flange sealing ring 354. It is locked to the battery pack housing frame 20 by bolts 356 inserted into the bolt mounting holes 355.

[0082] In a specific implementation, the first female connector 311 of the first pipeline can be directly connected to the system liquid cooling circuit. This disclosure does not limit the scope of the embodiments.

[0083] Referring to Figures 7 and 14, where Figure 14 is an exploded view of the assembly of a third pipeline according to an embodiment of this disclosure, the third pipeline 33 includes two first female connectors 331, two connecting pipes 332, and a second female connector 333. The second female connector 333 is a T-junction, with its two side interfaces connected to the corresponding first female connectors 331 via a connecting pipe 332. The second female connector 333 faces the second cooling subsystem 2 in the Z-direction to connect to the third liquid inlet 27 on the second cooling subsystem 2 side. The two first female connectors 331 face the first cooling subsystem 1 in the Z-direction to connect to the two first liquid inlets 12 of the corresponding cold plate assembly.

[0084] To facilitate assembly, the third pipe connection 332 is a flexible pipe, such as, but not limited to, a corrugated pipe or a flexible hose made of elastic material. Furthermore, the third pipe 33 may also include two fire-resistant sleeves 334, each wrapped around the outside of the third pipe connection 332, to improve reliability.

[0085] Referring to Figures 7 and 15, where Figure 15 is an exploded view of the assembly of a fourth pipeline according to an embodiment of this disclosure, the fourth pipeline 34 includes a first female connector 341, a connecting pipe 342, and a second female connector 343. The two ends of the connecting pipe 342 are connected to the first female connector 341 and the second female connector 343, respectively. The opening of the first female connector 341 can face the battery pack in the first direction X to connect to the first return interface 13 of the corresponding cold plate assembly. The opening of the second female connector 343 can face the second cooling subsystem 2 in the third direction Z to connect to the third return interface 28 on the side of the second cooling subsystem 2.

[0086] To facilitate assembly, the fourth conduit connection 342 is a flexible conduit, such as, but not limited to, a corrugated conduit or a flexible hose made of elastic material. Furthermore, the fourth conduit 34 may also include a fourth conduit fireproof sleeve 344 that wraps around the fourth conduit connection 342 to improve reliability.

[0087] Specifically, the circulation path of the coolant in the power battery cooling system is as follows:

[0088] First, coolant enters the first pipe 31 through the flange; second, coolant flows into the main distribution area 22 via the first pipe 31 and the second inlet port 25 on the side of the second cooling subsystem 2; third, coolant circulates through the main distribution area 22, with a first portion circulating within the second cooling subsystem 2 (bottom cooling system) via the second branch channel 21, and a second portion flowing into the third pipe 33 via the third inlet port 27; fourth, after the first portion of coolant has circulated in the second cooling subsystem 2, it flows to the main return area 23 of the second cooling subsystem 2; the second portion of coolant flows to the first cooling subsystem 1 (top cooling system) via the third pipe 33 and the first inlet port 12. (System); Fifth step, the second part of the coolant is split into two parts again, and is split into two branch harmonica tubes 113 through the two first inlet ports 12 of the first collector 111. The two parts of coolant flowing into the two branch harmonica tubes 113 flow back to the first collector 111 through the second collector 112 and the return harmonica tube 114, and flow to the fourth pipe 34 through the first return port 13; Sixth step, the coolant in the fourth pipe 34 flows to the main return area 23 through the third return port 28 on the side of the second cooling subsystem 2, and merges with the first part of the coolant; Seventh step, the merged coolant flows out of the cooling system through the second return port 26 and the second pipe 32 through another flange.

[0089] In addition to the aforementioned implementation scheme of the power battery cooling system, this disclosure also provides a vehicle including a battery pack 100, which employs the power battery cooling system 10 as described above. Based on this power battery cooling system, on the one hand, it can effectively improve the uniformity of the liquid cooling flow distribution at the bottom and top, avoid the adverse effects of complex shunt pipelines on flow resistance, and on the other hand, it can improve the integration.

[0090] It should be understood that other functional components of the vehicle can be implemented using existing technology, so they will not be described in detail here.

[0091] Furthermore, the ordinal numbers "first" and "second," etc., used herein are only for describing the composition or structure of the same function in the technical solution. It is understood that the use of the aforementioned ordinal numbers does not constitute a limitation on the understanding of the technical solution claimed in this disclosure.

[0092] In this disclosure, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," "fixing," etc., 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 disclosure according to the specific circumstances.

[0093] In the description of this disclosure, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this disclosure. In this disclosure, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this disclosure, as well as the features of different embodiments or examples.

[0094] The above are merely embodiments of this disclosure. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of this disclosure, and these improvements and modifications should also be considered within the scope of protection of this disclosure.

Claims

1. A power battery cooling system, characterized in that, It includes a first cooling subsystem, a second cooling subsystem, and a piping assembly; the first cooling subsystem and the second cooling subsystem each have a heat exchange area, and one of the first cooling subsystem and the second cooling subsystem is used to be installed at the top of the battery pack, and the other is used to be installed at the bottom of the battery pack; The first cooling subsystem includes a first flow channel, a first liquid inlet, and a first liquid return port; the first liquid inlet is connected to the inlet of the first flow channel, and the first liquid return port is connected to the outlet of the first flow channel. The second cooling subsystem includes a second branch channel, a main branch area, a main return area, a second liquid inlet, a second liquid return interface, a third liquid inlet, and a third liquid return interface; the main branch area is connected to the inlet of the second branch channel, and the main return area is connected to the outlet of the second branch channel; the second liquid inlet and the third liquid inlet are respectively connected to the main branch area, and the second liquid return interface and the third liquid return interface are respectively connected to the main return area; The third liquid inlet and the first liquid inlet, as well as the first liquid return and the third liquid return, are respectively connected through the pipeline group.

2. The power battery cooling system according to claim 1, characterized in that, The pipeline assembly is located on the same end as the first liquid inlet and the first liquid return port of the first cooling subsystem, and the second liquid inlet, the second liquid return port, the third liquid inlet port, and the third liquid return port of the second cooling subsystem.

3. The power battery cooling system according to claim 1 or 2, characterized in that, The first cooling subsystem includes multiple sets of cold plate assemblies, the first flow channel is formed inside each of the cold plate assemblies, and the cold plate assembly is provided with the first liquid inlet and the first liquid return interface; each of the cold plate assemblies is arranged sequentially along the second direction.

4. The power battery cooling system according to claim 3, characterized in that, The cold plate assembly includes a first collector, a second collector, a diversion harmonica tube, and a return harmonica tube. One end of the diversion harmonica tube and the return harmonica tube are inserted into the first collector, and the other end is inserted into the second collector. The tube bodies of the diversion harmonica tube and the return harmonica tube extend along a first direction and are arranged at intervals in a second direction. The first liquid inlet and the first liquid return outlet are disposed on the first collector.

5. The power battery cooling system according to claim 4, characterized in that, The first collector includes a first chamber and a second chamber that are separated. The first inlet port and the diversion harmonica tube are connected to the first chamber of the first collector, and the first return port and the return harmonica tube are connected to the second chamber of the first collector.

6. The power battery cooling system according to claim 5, characterized in that, The first collector has two first cavities, which are located on both sides of the second cavity of the first collector.

7. The power battery cooling system according to claim 4, 5, or 6, characterized in that, The second collector includes a first cavity and a second cavity that are separated. There are multiple shunt harmonica tubes and multiple return harmonica tubes. In the second direction, a portion of the multiple shunt harmonica tubes and multiple return harmonica tubes are connected to the first cavity of the second collector, and another portion is connected to the second cavity of the second collector.

8. The power battery cooling system according to any one of claims 1 to 7, characterized in that, The second cooling subsystem includes a flow channel plate and a heat exchange plate. The flow channel plate includes grooves corresponding to the second branch flow channel, the main branch area, and the main return area. The heat exchange plate is stacked on the surface of the flow channel plate where the grooves are formed, enclosing the second branch flow channel, the main branch area, and the main return area. The second liquid inlet, the second liquid return, the third liquid inlet, and the third liquid return are disposed on the heat exchange plate, and the heat exchange plate forms the heat exchange area of ​​the second cooling subsystem.

9. The power battery cooling system according to any one of claims 1 to 8, characterized in that, The number of the third liquid inlet and the third liquid return are the same as the number of the cold plate assemblies in the first cooling subsystem.

10. The power battery cooling system according to any one of claims 1 to 8, characterized in that, In the first direction, the main distribution area is located close to the second branch channel, and the main return area is located on the side of the main distribution area away from the second branch channel.

11. The power battery cooling system according to any one of claims 1 to 10, characterized in that, The second flow channel includes multiple sub-flow channels. In the second direction, the upstream flow channel section with an inlet of each sub-flow channel is located in the middle region of the heat dissipation area of ​​the second cooling subsystem, and the downstream flow channel section with an outlet of each sub-flow channel is located in the two side regions of the heat dissipation area of ​​the second cooling subsystem.

12. The power battery cooling system according to claim 11, characterized in that, In the second direction, the inlet of each sub-channel of the second branch channel is located in the middle, and the outlet of each sub-channel of the second branch channel is located on both sides of the inlet; the total return region surrounds the two ends of the total branch region in the second direction.

13. The power battery cooling system according to any one of claims 1 to 12, characterized in that, The pipeline group includes a first pipeline, a second pipeline, a third pipeline and a fourth pipeline. One end of the first pipeline is connected to the second liquid inlet interface, and the other end is used to connect to the output pipeline of the system liquid cooling circuit. One end of the second pipeline is connected to the second return liquid interface, and the other end is used to connect to the recovery pipeline of the system liquid cooling circuit; the third pipeline is connected between the third liquid inlet interface and the first liquid inlet interface, and the fourth pipeline is connected between the first return liquid interface and the third return liquid interface.

14. The power battery cooling system according to claim 13, characterized in that, In the first direction, the piping group is located on the same end side as the first liquid inlet and the first liquid return port of the first cooling subsystem, and the second liquid inlet, the second liquid return port, the third liquid inlet and the third liquid return port of the second cooling subsystem.

15. A battery pack, characterized in that, The battery pack includes a plurality of cells arranged in sequence and a cooling system, wherein the cooling system is the power battery cooling system according to any one of claims 1 to 14.

16. A vehicle, characterized in that, The vehicle includes a battery pack, which employs the battery pack described in claim 15.

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