A power battery cooling system, battery pack and vehicle

Abstract

This invention discloses a power battery cooling system, a battery pack, and a vehicle. The power battery cooling system includes a first cooling subsystem, a second cooling subsystem, and a piping assembly. 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. This configuration effectively improves the uniformity of liquid cooling flow distribution at the bottom and top while ensuring good heat dissipation efficiency.

Description

Technical Field

[0001] This invention relates to the field of automotive technology, specifically to a power battery cooling system, a battery pack, and a vehicle. Background Technology

[0002] 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.

[0003] In view of this, there is an urgent need to provide solutions for cooling existing battery packs in order to overcome the above-mentioned shortcomings. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention 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.

[0005] A first aspect of the present invention provides a power battery cooling system, comprising a first cooling subsystem, a second cooling subsystem, and a piping assembly; the first and second cooling subsystems each have a heat exchange area, one of which is disposed at the top of the battery pack and the other at the bottom of the battery pack; 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, and the first and third liquid return ports are respectively connected through 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.

[0006] Based on the first aspect, the present invention also provides a first embodiment of the first aspect: the pipeline 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. In this way, by configuring the pipeline assembly and the interfaces of the first and second cooling subsystems on the same end side, for example, but not limited to, the pipeline assembly can be located above the main distribution area and the main return area of ​​the first cooling subsystem, which can effectively improve integration and further avoid the adverse effects of complex branch pipelines on flow resistance. Furthermore, by supplementing the pipeline assembly with the main distribution area and the main return area on the same end side, the flow resistance of the entire power battery cooling system can be effectively reduced, further improving heat dissipation efficiency.

[0007] Based on the first aspect, or the first embodiment of the first aspect, the present invention also provides a second embodiment of the first aspect: a first cooling subsystem includes multiple sets of cold plate assemblies, a second flow channel is formed inside each cold plate assembly, and a first liquid inlet and a first liquid return interface are 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. Exemplarily, 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.

[0008] Based on the second embodiment of the first aspect, the present invention also provides a third embodiment of the first aspect: 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 being inserted into the first current collector, and the other end being 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 arranged at intervals in a second direction; a first liquid inlet and a first liquid return outlet are disposed on the first current collector; wherein, the first direction and the second direction are two directions in the cell arrangement plane. In practical applications, the first current collector may include a first cavity and a second cavity that are separated, the first liquid inlet and the shunt harmonica tube communicating with the first cavity of the first current collector, and the first liquid return outlet and the return harmonica tube communicating 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.

[0009] Based on the third embodiment of the first aspect, the present invention also provides a fourth embodiment of the first aspect: the first collector has two first cavities, which are respectively disposed 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.

[0010] Based on the fourth embodiment of the first aspect, the present invention also provides a fifth embodiment of the first aspect: the second collector includes a first cavity and a second cavity 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 are connected to the first cavity of the second collector, and another portion is connected to the second cavity of the second collector. This avoids turbulence affecting the flow of coolant within the second collector, thereby improving heat exchange efficiency.

[0011] Based on the first aspect, the present invention also provides a sixth embodiment of the first aspect: 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, respectively. The heat exchange plate is stacked on the surface of the grooves of 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.

[0012] 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.

[0013] Based on the sixth embodiment of the first aspect, the present invention also provides a seventh embodiment of the first aspect: 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 a better degree of integration.

[0014] Based on the seventh embodiment of the first aspect, the present invention also provides an eighth embodiment of the first aspect: the second flow channel includes multiple sub-flow channels, wherein, 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, 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. In this way, the low-temperature coolant entering each sub-flow channel through the inlet first cools the battery cells located in the middle with relatively poor heat dissipation conditions, and then cools the battery cells located on the sides, thus avoiding thermal runaway. Overall, the temperature of each battery cell tends to be more uniform.

[0015] For example, in the second direction Y, the inlet of each sub-channel of the second branch channel can 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. 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.

[0016] Based on the eighth embodiment of the first aspect, the present invention also provides a ninth embodiment of the first aspect: the pipeline group further 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 port, and the other end is used to connect to the output pipeline of the system's liquid cooling circuit. One end of the second pipeline is connected to the second liquid return port, and the other end is used to connect to the recovery pipeline of the system's liquid cooling circuit. The third pipeline is connected between the third liquid inlet port and the first liquid inlet port, and the fourth pipeline is connected between the first liquid return port and the third liquid return port. Thus, a pipeline group with external connecting pipelines is formed, which has good operability.

[0017] For example, in the first direction X, 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.

[0018] A second aspect of the invention provides a battery pack comprising a plurality of cells arranged in sequence and a cooling system as described above.

[0019] A third aspect of the invention provides a vehicle including a battery pack employing the battery pack described above. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of a battery pack provided in an embodiment of this application;

[0021] Figure 2 for Figure 1 An exploded view of the assembly of the power battery cooling system shown in the figure;

[0022] Figure 3 A schematic diagram of the cold plate assembly of a first cooling subsystem provided in an embodiment of this application;

[0023] Figure 4 An exploded view of the assembly of a second cooling subsystem provided in this application embodiment;

[0024] Figure 5 for Figure 4 The front view of the heat spreader shown;

[0025] Figure 6 for Figure 4 The front view of the flow channel plate shown;

[0026] Figure 7 An isometric view of a piping assembly provided in an embodiment of this application;

[0027] Figure 8 for Figure 3 AA section view in the middle;

[0028] Figure 9 for Figure 3 BB section view in the middle;

[0029] Figure 10 An exploded view of the assembly of a first pipeline provided in an embodiment of this application;

[0030] Figure 11 An exploded view of the assembly of a second pipeline provided in an embodiment of this application;

[0031] Figure 12An isometric drawing of a flange provided for an embodiment of this application;

[0032] Figure 13 for Figure 12 The diagram shows the assembly relationship between the flange and the battery pack.

[0033] Figure 14 An exploded view of the assembly of a third pipeline provided in this application embodiment;

[0034] Figure 15 An exploded view of the assembly of a fourth pipeline provided in an embodiment of this application.

[0035] In the picture:

[0036] Battery pack 100, cooling system 10, casing frame 20, protective plate 30;

[0037] First cooling subsystem 1, first branch channel 11, first collector 111, first sealing plate 1111, second collector 112, second sealing plate 1121, branch harmonica tube 113, return harmonica tube 114, first liquid inlet 12, first liquid return 13;

[0038] Second cooling subsystem 2, flow channel plate 211, heat distribution plate 212, second branch flow channel 21, main branch area 22, main return area 23, second liquid inlet 25, second liquid return interface 26, third liquid inlet 27, third liquid return interface 28, reinforcing groove 29, reinforcing rib 210;

[0039] Piping assembly 3, First pipe 31, First pipe first female connector 311, First pipe connecting pipe 312, First pipe second female connector 313, First pipe fireproof sleeve 314, Second pipe 32, Second pipe first female connector 321, Second pipe connecting pipe 322, Second pipe second female connector 323, Second pipe fireproof sleeve 324, Third pipe 33, Third pipe first female connector 331, Third pipe connecting pipe 332, Third pipe second female connector 333, Third pipe fireproof sleeve 334, Fourth pipe 34, Fourth pipe first female connector 341, Fourth pipe connecting pipe 342, Fourth pipe second female connector 343, Fourth pipe fireproof sleeve 344, Flange 35, Flange face 351, Flange water tap 352, Flange pipe male connector 353, Flange sealing ring 354, Bolt mounting hole 355, Bolt 356. Detailed Implementation

[0040] To enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0041] Please see Figure 1 and Figure 2 ,in, Figure 1 This is a schematic diagram of the overall structure of a battery pack provided in an embodiment of this application. Figure 2 for Figure 1 The diagram shows an exploded view of the power battery cooling system assembly.

[0042] The battery pack 100 provided in this embodiment includes a plurality of battery cells (not shown in the figure) arranged sequentially within the casing frame 20 and a cooling system 10. In specific implementations, the battery cells can be square or cylindrical, and this embodiment does not limit this. For ease of description, two directions are defined in the plane in which the plurality of battery cells are arranged: a first direction X and a second direction Y, and the 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.

[0043] Figure 1 The diagram illustrates 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 into 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.

[0044] 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.

[0045] Combination Figure 2 As shown, 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 being constructed from a single continuous heat exchange surface, and also includes the case of being constructed from 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 other side of the battery pack 100 opposite to the battery cell terminals. For example, as... Figure 2As shown, the first cooling subsystem 1 can be located at the top of the battery pack 100, and its heat exchange area includes multiple heat exchange surfaces spaced apart by each bellows tube, used to cool the terminals at the top of each cell; the second cooling subsystem 2 can be located at the bottom of the battery pack 100, and its heat exchange area is a continuous heat exchange surface provided by a heat spreader, used to cool the bottom of each cell. It should be understood that in other specific implementations, the first cooling subsystem 1 and the second cooling subsystem 2 can also be arranged in reverse relative to the cells, that is, the first cooling subsystem 1 is located at the bottom of the battery pack 100, and the second cooling subsystem 2 is located at the top of the battery pack 100, and can still cool and dissipate heat to the cells on the corresponding sides through their respective heat exchange areas. This application does not limit the scope of the embodiments.

[0046] The first cooling subsystem 1 includes multiple first distribution channels 11, first liquid inlet ports 12, and first liquid return ports 13. Please refer to [the documentation for the first part of the text]. Figure 3 This figure is an axonal schematic diagram of a first cooling subsystem provided in an embodiment of this application.

[0047] 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.

[0048] 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 the following: Figure 4 , Figure 5 and Figure 6 ,in, Figure 4 This is an exploded view of the assembly of a second cooling subsystem provided in an embodiment of this application. Figure 5 for Figure 4 The front view of the heat spreader shown. Figure 6 for Figure 4 The front view of the flow channel plate shown.

[0049] 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.

[0050] 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 application does not limit the implementation.

[0051] Pipeline group 3 includes a first pipeline 31, a second pipeline 32, a third pipeline 33, and a fourth pipeline 34. Please refer to the following: Figure 2 and Figure 7 ,in, Figure 7 This is an isometric view of a piping assembly provided in an embodiment of this application. In the first direction X, the piping 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.

[0052] 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.

[0053] 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.

[0054] 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.

[0055] 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.

[0056] In addition, in the power battery cooling system provided in this application 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 set 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.

[0057] To better understand the technical solutions and effects of this application, without loss of generality, the specific embodiments will be described in detail below with reference to the accompanying drawings.

[0058] Combination Figure 2 , Figure 3 , Figure 8 and Figure 9As shown, where, Figure 8 for Figure 3 AA section view, Figure 9 for Figure 3 The figure shows a BB cross-sectional view. Exemplarily, the first cooling subsystem 1 includes three sets of cold plate assemblies, with a second flow channel 21 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 application does not limit the scope of the embodiments.

[0059] like Figure 3 As shown, 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 can improve 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.

[0060] 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.

[0061] 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.

[0062] 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.

[0063] like Figure 8 As shown, 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 distribution uniformity, the flow resistance within the cold plate assembly can be further rationally controlled.

[0064] In a specific implementation, the second collector 112 may also include a first cavity and a second cavity separated by a second sealing piece 1121, such as... Figure 9 As shown, 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.

[0065] In this embodiment, the cold plate assembly has two flow-diverting harmonica tubes 113 and two return harmonica tubes 114. Of course, in other specific implementations, the actual number of flow-diverting harmonica tubes 113 and two return harmonica tubes 114 may be one, for example, but not limited to, one. This can be determined based on the overall product design requirements. This application does not limit the specific implementation.

[0066] 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.

[0067] 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. Preferably, the leakage current is <1mA after 15 minutes of flame impact at 1000℃ and DC 4000V.

[0068] For example Figure 4, Figure 5 and Figure 6 As shown, 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 of the flow channel plate 211, and together they form the second branch flow channel 21, the main branch area 22 and the main return area 23, and the heat exchange area of ​​the second cooling subsystem 2 is formed by the heat exchange plate 212.

[0069] 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 heat spreader 212 and communicate with the main distribution area 22 and the main return area 23 respectively through through holes in the heat spreader 212. The number of third liquid inlets 27 and third liquid return 28 is the same as that of the cold plate assembly, and they are arranged in a one-to-one correspondence. Figure 4 and Figure 5 As shown, 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 the fourth pipe 34.

[0070] 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.

[0071] like Figure 6 As shown, in the first direction X, the main distribution area 22 is located 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.

[0072] 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.

[0073] 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.

[0074] 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.

[0075] 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.

[0076] 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.

[0077] For example Figure 7 As shown, 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.

[0078] Combination Figure 7 and Figure 10 As shown, where, Figure 10 This is an exploded view of the assembly of a first pipeline provided in an embodiment of this application. 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 liquid cooling circuit side of the system. 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.

[0079] 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.

[0080] Combination Figure 7 and Figure 11 As shown, where, Figure 11 This is an exploded view of the assembly of a second pipeline provided in an embodiment of this application. 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 liquid cooling circuit side of the system. 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 side of the second cooling subsystem 2.

[0081] 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.

[0082] In practice, the first pipe 31 and the second pipe 32 can be connected to the liquid cooling circuit side of the system via flange 35. Please refer to [link / reference needed]. Figure 7 and Figure 12 ,in, Figure 12 This is an isometric view of a flange provided in an embodiment of this application. 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.

[0083] 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 the above. Figure 13 The image is Figure 12 The diagram shows the assembly relationship between the flange and the battery pack. 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, while the remaining part is located inside the battery pack. The flange face 351 is tightly fitted against the inner wall of the battery pack housing frame, and is sealed by the flange sealing ring 354. It is then locked to the battery pack housing frame 20 by bolts 356 inserted into the bolt mounting holes 355.

[0084] In a specific implementation, the first female connector 311 of the first pipeline can be directly connected to the system liquid cooling circuit. This application does not limit the specific implementation.

[0085] Combination Figure 7 and Figure 14 As shown, where, Figure 11 This is an exploded view of the assembly of a third pipeline provided in an embodiment of this application. The third pipeline 33 includes two third pipeline first female plugs 331, two third pipeline connecting pipes 332, and one third pipeline second female plug 333. The third pipeline second female plug 333 has a tee structure, and its two side interfaces are respectively connected to the corresponding third pipeline first female plug 331 through a third pipeline connecting pipe 332. The third pipeline second female plug 333 faces the second cooling subsystem 2 in the third direction Z so as to connect with the third liquid inlet interface 27 on the side of the second cooling subsystem 2. The two third pipeline first female plugs 331 face the first cooling subsystem 1 in the third direction Z so as to connect with the two first liquid inlet interfaces 12 of the corresponding cold plate assembly respectively.

[0086] 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.

[0087] Combination Figure 7 and Figure 15 As shown, where, Figure 15 This is an exploded view of the assembly of a fourth pipeline provided in an embodiment of this application. 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 with 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 with the third return interface 28 on the side of the second cooling subsystem 2.

[0088] 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.

[0089] Specifically, the circulation path of the coolant in the power battery cooling system is as follows:

[0090] 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. It is split into two parts through the two first inlet ports 12 of the first collector 111 and into two branch harmonica tubes 113. 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 then 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.

[0091] In addition to the aforementioned implementation scheme of the power battery cooling system, this application embodiment also provides a vehicle, which includes a battery pack 100, and the battery pack 100 adopts 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 the complex shunt pipeline on the flow resistance, and on the other hand, it can improve the integration.

[0092] 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.

[0093] 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 for which protection is sought in this application.

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

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 located at the top of the battery pack, while the other is located 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; The pipeline assembly is located on the same end 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.

2. The power battery cooling system according to claim 1, characterized in that, The first cooling subsystem includes multiple sets of cold plate assemblies, the second 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.

3. The power battery cooling system according to claim 2, 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.

4. The power battery cooling system according to claim 3, characterized in that, The first collector includes a first chamber and a second chamber that are separated from each other. 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.

5. The power battery cooling system according to claim 4, characterized in that, The first collector has two first cavities, which are located on both sides of the second cavity of the first collector.

6. The power battery cooling system according to claim 4 or 5, 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 a 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.

7. The power battery cooling system according to claim 1, 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.

8. The power battery cooling system according to claim 7, 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.

9. The power battery cooling system according to claim 7, 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.

10. The power battery cooling system according to any one of claims 7 to 9, 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.

11. The power battery cooling system according to claim 10, 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.

12. The power battery cooling system according to claim 1, 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.

13. The power battery cooling system according to claim 12, characterized in that, In the 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.

14. 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 13.

15. A vehicle, characterized in that, The vehicle includes a battery pack, which employs the battery pack described in claim 14.

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