Liquid cooling plate and battery pack

Abstract

The utility model discloses a liquid cooling plate and a battery pack and relates to the technical field of battery thermal management. The liquid cooling plate comprises a liquid cooling plate body, the liquid cooling plate body is provided with a first liquid inlet and outlet, a second liquid inlet and outlet, a first main flow channel, a second main flow channel and a plurality of branch flow channels, the first liquid inlet and outlet is communicated with the first main flow channel, the second liquid inlet and outlet is communicated with the second main flow channel, and the branch flow channels are connected between the first main flow channel and the second main flow channel in parallel; the reversing valve group comprises a valve body, a valve core and a controller, one end of the valve body is connected with the first liquid inlet and outlet and the second liquid inlet and outlet, the other end of the valve body is used for being connected with the liquid cooling unit, and the controller is used for controlling switching of the valve core. The liquid cooling plate body is simple in structure and easy to design and manufacture; the reversing valve group changes the flow direction of the cooling liquid in the liquid cooling plate body through switching of the valve core, so that the temperature difference of the battery cells in the battery pack can be effectively reduced, and the consistency of the performance of the battery cells in the battery pack is ensured.

Description

Technical Field

[0001] The present application relates to the technical field of battery thermal management, and in particular to a liquid cooling plate and a battery pack. Background Art

[0002] Cold plate liquid cooling is the mainstream thermal management solution for energy storage battery packs. The cold plate is typically installed at the bottom of the battery as a support base. During operation, low-temperature coolant flows into the cold plate's inlet, passes through the cold plate's flow channel, and after heat exchange with the battery, becomes high-temperature coolant, which then flows out of the cold plate's outlet. However, the temperature difference between the batteries near the inlet and outlet is significant. This temperature difference accelerates battery aging near the outlet, and due to the "barrel effect," further accelerates the decline in the available capacity of the entire battery pack.

[0003] Current liquid cooling plates often utilize complex flow channel designs to control the coolant flow rate and pressure, thereby improving the temperature difference between cells within a battery pack. However, these complex liquid cooling plates are expensive to manufacture, and in actual use, the temperature difference between cells remains large. Therefore, effectively reducing the temperature difference between cells within a battery pack is a pressing issue for the energy storage industry. Utility Model Content

[0004] In view of this, the purpose of this application is to provide a liquid cooling plate and a battery pack to solve at least one of the above technical problems.

[0005] In the first aspect, the present application provides a liquid cooling plate, comprising: a liquid cooling plate body, on which a first liquid inlet and outlet, a second liquid inlet and outlet, a first main channel, a second main channel, and a plurality of branch channels are provided, the first liquid inlet and outlet are connected to the first main channel, the second liquid inlet and outlet are connected to the second main channel, and the plurality of branch channels are arranged in parallel and connected between the first main channel and the second main channel; and a reversing valve group, the reversing valve group comprises a valve body, a valve core, and a controller, one end of the valve body is connected to the first liquid inlet and outlet and the second liquid inlet and outlet, the other end of the valve body is used to connect to the liquid cooling unit, and the controller is used to control the switching of the valve core to change the flow direction of the cooling liquid delivered by the liquid cooling unit in the liquid cooling plate body.

[0006] In combination with the first aspect, in some optional embodiments, the first main channel includes a first flow channel portion and a second flow channel portion, the second main channel includes a third flow channel portion and a fourth flow channel portion, the first flow channel portion and the third flow channel portion extend in opposite directions along the first direction, the two ends of the first flow channel portion are respectively connected to the first liquid inlet and outlet and the second flow channel portion, the two ends of the third flow channel portion are respectively connected to the second liquid inlet and outlet and the fourth flow channel portion, the second flow channel portion and the fourth flow channel portion both extend along the second direction, and the first direction and the second direction are perpendicular to each other.

[0007] In combination with the first aspect, in some optional embodiments, multiple branch channels are arranged at equal intervals in the second direction between the second flow channel portion and the fourth flow channel portion, each branch channel extends along the first direction and has its two ends connected to the second flow channel portion and the fourth flow channel portion respectively.

[0008] In combination with the first aspect, in some optional embodiments, the liquid cooling plate body is rectangular, having two side edges arranged along a first direction and another two side edges arranged along a second direction, and the first liquid inlet and outlet and the second liquid inlet and outlet are arranged in the middle of a side edge of the liquid cooling plate body arranged along the first direction.

[0009] In combination with the first aspect, in some optional embodiments, the valve body is provided with a first docking port, a second docking port, a valve group liquid inlet, and a valve group liquid outlet, the first docking port and the second docking port are connected to the first liquid inlet and outlet and the second liquid inlet and outlet respectively, and the valve group liquid inlet and the valve group liquid outlet are used to connect to the liquid cooling unit.

[0010] In combination with the first aspect, in some optional embodiments, the valve core includes a straight-through valve core and a reversing valve core.

[0011] In combination with the first aspect, in some optional embodiments, the straight-through valve core has a first valve core channel and a second valve core channel, the first valve core channel is used to connect the first docking port and the valve group liquid inlet, and the second valve core channel is used to connect the second docking port and the valve group liquid outlet; the reversing valve core has a third valve core channel and a fourth valve core channel, the third valve core channel is used to connect the second docking port and the valve group liquid inlet, and the fourth valve core channel is used to connect the first docking port and the valve group liquid outlet.

[0012] In a second aspect, the present application provides a battery pack comprising a liquid cooling plate and a plurality of battery cells according to any one of the embodiments of the first aspect above, wherein the liquid cooling plate is in contact with the plurality of battery cells for cooling and dissipating heat.

[0013] In combination with the second aspect, some optional embodiments further include a BMS battery management system, which is communicatively connected to the controller of the reversing valve group of the liquid cooling plate and multiple battery cells, and is used to detect the temperature of the multiple battery cells and transmit it to the controller so that the controller can control the switching of the valve core accordingly.

[0014] In combination with the second aspect, in some optional implementations, the controller is used to control the switching of the valve core when the temperature difference of the battery core exceeds a set value.

[0015] Based on the above technical solution, the liquid cooling plate and battery pack provided by the present application, the liquid cooling plate includes a liquid cooling plate body and a reversing valve group. The liquid cooling plate body has a simple structure and is easy to design and manufacture. The reversing valve group changes the flow direction of the coolant in the liquid cooling plate body by switching the valve core, so that the low-temperature coolant cools the battery cells through which the high-temperature coolant that originally absorbs the heat of the battery cells flows, and the high-temperature coolant that absorbs the heat of the battery cells cools the battery cells through which the low-temperature coolant originally flows, which is equivalent to increasing the cooling effect on the high-temperature battery cells and reducing the cooling effect on the low-temperature battery cells, thereby effectively reducing the temperature difference of the battery cells in the battery pack and ensuring the consistency of the performance of the battery cells in the battery pack. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0017] Figure 1 A schematic structural diagram of a liquid cooling plate provided in an embodiment of the present application.

[0018] Figure 2 A schematic structural diagram of a liquid cooling plate of a battery pack provided in an embodiment of the present application in a first working state.

[0019] Figure 3 A schematic structural diagram of a liquid cooling plate of a battery pack in a second working state provided in an embodiment of the present application.

[0020] Figure 4 A schematic diagram of the process flow of a liquid cooling plate of a battery pack provided in an embodiment of the present application during operation.

[0021] Figure numerals: 100, liquid cooling plate; 10, liquid cooling plate body; 11, first liquid inlet and outlet; 12, second liquid inlet and outlet; 13, first main channel; 131, first flow channel portion; 132, second flow channel portion; 14, second main channel; 141, third flow channel portion; 142, fourth flow channel portion; 15, branch channel; 20, reversing valve group; 21, valve body; 211, first docking port; 212, second docking port; 213, valve group liquid inlet; 214, valve group liquid outlet; 22, straight-through valve core; 221, first valve core channel; 222, second valve core channel; 23, reversing valve core; 231, third valve core channel; 232, fourth valve core channel; 200, BMS battery management system. DETAILED DESCRIPTION

[0022] Specific embodiments of the present application will be described in detail below with reference to the accompanying drawings. It is apparent that the described embodiments are only a portion of the embodiments of the present application, and not all of the embodiments. All other embodiments derived by persons of ordinary skill in the art based on the description of this application without inventive effort are intended to fall within the scope of protection of this application.

[0023] In the description of this application, unless otherwise specified or limited, the terms "connect," "dispose," and "install" should be understood broadly. For example, "connect" can mean a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can mean that two components are internally connected. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0024] The terms "upper", "lower", "left", "right", "front", "back", "center", "top", "bottom", "inside", "outside", "vertical", "horizontal", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the accompanying drawings, or the orientation or position relationship in which the product of the application is usually placed when used. They are only for the convenience of description and simplification of description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, they should not be understood as limiting the present application.

[0025] The terms "first," "second," "third," etc. are merely used to distinguish elements of similar nature, and do not indicate or imply relative importance or a particular order, unless expressly specified and limited otherwise.

[0026] The terms "comprises," "includes," "has," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not expressly listed or inherent to such process, method, article, or apparatus. In the absence of more limitations, an element defined by the phrase "comprising a ..." does not preclude the presence of additional identical elements in the process, method, article, or apparatus that includes the element.

[0027] The term "plurality" means two or more (including two).

[0028] The term "and / or" is a description of the association relationship of associated objects, indicating that three relationships can exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone.

[0029] The terms "one embodiment," "as an example," "in one implementation," and the like mean that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example may be included in at least one embodiment or example of the present application. The schematic representations of such terms do not necessarily refer to the same embodiment, nor are they mutually exclusive independent or alternative embodiments. The embodiments and features within the embodiments of the present application may be combined in appropriate ways unless there is a conflict.

[0030] Figure 1 A schematic diagram of the structure of a liquid cooling plate 100 provided in an embodiment of the present application is shown in FIG. Figure 1 As shown, an embodiment of the present application provides a liquid cooling plate 100 , including a liquid cooling plate body 10 and a reversing valve assembly 20 .

[0031] The liquid cooling plate body 10 has a simple structure, making it easy to design and manufacture. Specifically, the liquid cooling plate body 10 is rectangular, with two sides extending along a first direction and two sides extending along a second direction, wherein the first and second directions are perpendicular. The liquid cooling plate body 10 is provided with a first liquid inlet and outlet 11, a second liquid inlet and outlet 12, a first main channel 13, a second main channel 14, and multiple branch channels 15.

[0032] The first liquid inlet and outlet 11 and the second liquid inlet and outlet 12 are arranged in the middle of a side edge arranged along the first direction of the liquid cooling plate body 10. When either one of the first liquid inlet and outlet 11 and the second liquid inlet and outlet 12 serves as the inlet of the cooling liquid, the other serves as the outlet.

[0033] The first main channel 13 and the second main channel 14 are arranged symmetrically about the central axis of the liquid cooling plate body 10 in the first direction. The first main channel 13 includes a first channel portion 131 and a second channel portion 132, and the second main channel 14 includes a third channel portion 141 and a fourth channel portion 142. The first channel portion 131 and the third channel portion 141 extend in opposite directions along the first direction. The first channel portion 131 connects the first liquid inlet and outlet 11 and the second channel portion 132 at both ends, while the third channel portion 141 connects the second liquid inlet and outlet 12 and the fourth channel portion 142 at both ends. The second channel portion 132 and the fourth channel portion 142 both extend in the second direction.

[0034] Multiple branch channels 15 are arranged in parallel and at equal intervals in the second direction between the second channel portion 132 and the fourth channel portion 142 . Each branch channel 15 extends along the first direction and has two ends connected to the second channel portion 132 and the fourth channel portion 142 .

[0035] One end of the reversing valve assembly 20 is connected to the first and second liquid inlet and outlet ports 11 and 12 of the liquid cooling plate body 10. The other end of the reversing valve assembly 20 is connected to the liquid cooling unit. The reversing valve assembly 20 is used to change the flow direction of the coolant delivered by the liquid cooling unit within the liquid cooling plate body 10. Specifically, the reversing valve assembly 20 includes a valve body 21, a through valve core 22, a reversing valve core 23, and a controller (not shown).

[0036] The valve body 21 is provided with a first docking port 211, a second docking port 212, a valve block liquid inlet 213, and a valve block liquid outlet 214. The first docking port 211 is connected to the first liquid inlet and outlet 11 of the liquid cooling plate body 10, the second docking port 212 is connected to the second liquid inlet and outlet 12 of the liquid cooling plate body 10, the valve block liquid inlet 213 is used to connect to the liquid outlet of the liquid cooling unit, and the valve block liquid outlet 214 is used to connect to the liquid inlet of the liquid cooling unit.

[0037] The through-hole valve core 22 and the reversing valve core 23 are both disposed within the valve body 21. The through-hole valve core 22 has a first valve core channel 221 and a second valve core channel 222. The first valve core channel 221 is used to connect the first docking port 211 with the valve block liquid inlet 213, and the second valve core channel 222 is used to connect the second docking port 212 with the valve block liquid outlet 214. The reversing valve core 23 has a third valve core channel 231 and a fourth valve core channel 232. The third valve core channel 231 is used to connect the second docking port 212 with the valve block liquid inlet 213, and the fourth valve core channel 232 is used to connect the first docking port 211 with the valve block liquid outlet 214.

[0038] The controller is used to control the switching between the through valve core 22 and the reversing valve core 23. The switching mode can be mechanical, electric, hydraulic, electro-hydraulic, etc., and this application does not limit this, so the specific components that perform the switching action are not shown in the figure.

[0039] Figure 2 This is a structural diagram of a liquid cooling plate 100 of a battery pack provided in an embodiment of the present application in a first working state. Figure 3 A schematic structural diagram of a liquid cooling plate 100 of a battery pack provided in an embodiment of the present application in a second working state, as shown in FIG. Figure 2 and Figure 3 As shown, an embodiment of the present application further provides a battery pack, including the above-mentioned liquid cooling plate 100, a plurality of battery cells (not shown in the figure), and a BMS battery management system 200.

[0040] The liquid cooling plate body 10 is positioned at the bottom of the battery cells. The valve inlet 213 and valve outlet 214 of the reversing valve assembly 20 are connected to a liquid cooling unit, which is responsible for cooling and delivering the coolant. The BMS battery management system 300 is connected to the controller of the reversing valve assembly 20 and the battery cells to detect the temperature of the battery cells and transmit it to the controller. Based on the battery cell temperature, the controller switches the through valve core 22 and the reversing valve core 23 to change the flow direction of the coolant.

[0041] like Figure 2 As shown, combined Figure 1 When the liquid cooling plate 100 is in the first working state, the first valve core channel 221 of the direct valve core 22 is connected to the first docking port 211 and the valve group liquid inlet 213, and the second valve core channel 222 is connected to the second docking port 212 and the valve group liquid outlet 214. Figure 2 As shown by the middle arrow, the coolant flows out of the liquid cooling unit, flows through the valve group liquid inlet 213, the first valve core channel 221, the first docking port 211 in sequence, and then enters the first liquid inlet and outlet 11, then flows through the first main channel 13, multiple branch channels 15, the second main channel 14, the second liquid inlet and outlet 12, and then enters the second docking port 212, and then flows through the second valve core channel 222 and the valve group liquid outlet 214 and returns to the liquid cooling unit, forming a cycle.

[0042] After the liquid cooling plate 100 has operated in the first operating state for a period of time, the temperature of the coolant in each branch channel 15 gradually increases along the flow direction of the coolant, because the first main channel 13 contains low-temperature coolant and the second main channel 14 contains high-temperature coolant that absorbs heat from the battery cells. This causes the temperature of the battery cells at the fourth channel portion 142 of the second main channel 14 to be relatively higher than the temperature of the battery cells at the second channel portion 132 of the first main channel 13. Over time, the temperature difference between the two battery cells increases further. At this point, based on the battery cell temperature detected by the BMS battery management system 300, the controller of the reversing valve assembly 20 switches the liquid cooling plate 100 to the second operating state.

[0043] like Figure 3 As shown, combined Figure 1 When the liquid cooling plate 100 is in the second working state, the third valve core channel 231 of the reversing valve core 23 is connected to the second docking port 212 and the valve group liquid inlet 213, and the fourth valve core channel 232 is connected to the first docking port 211 and the valve group liquid outlet 214. Figure 3As shown by the middle arrow, the coolant flows out of the liquid cooling unit, flows through the valve group liquid inlet 213, the third valve core channel 231, the second docking port 212 in sequence, and then enters the second liquid inlet and outlet 12, and then flows through the second main channel 14, multiple branch channels 15, the first main channel 13, the first liquid inlet and outlet 11 and then enters the first docking port 211, and then flows through the fourth valve core channel 232 and the valve group liquid outlet 214 and returns to the liquid cooling unit, forming a cycle.

[0044] In the second working state, the temperature of the battery cells at the fourth flow channel portion 142 will be relatively lower than the temperature of the battery cells at the second flow channel portion 132, which is equivalent to improving the cooling effect on the high-temperature battery cells at the fourth flow channel portion 142 and reducing the cooling effect on the low-temperature battery cells at the second flow channel portion 132, thereby effectively reducing the temperature difference of the battery cells in the battery pack and ensuring the consistency of the battery cell performance in the battery pack.

[0045] Furthermore, the controller of the reversing valve assembly 20 may be configured to switch the working state of the liquid cooling plate 100 to reduce the temperature difference of the battery cells when the temperature difference of the battery cells on the liquid cooling plate 100 exceeds a set value.

[0046] Specifically, Figure 4 A schematic diagram of the operation of a liquid cooling plate 100 of a battery pack provided in an embodiment of the present application is shown in FIG. Figure 4 As shown, after the battery pack is operational, the controller of the reversing valve assembly 20 is powered on, the liquid cooling plate 100 is in the first operating state, and the controller communicates with the battery management system (BMS) 300 to obtain the temperature of each battery cell in the battery pack. The controller then screens the lowest temperature T1 of the battery cell at the second flow channel 132 and the highest temperature T2 of the battery cell at the fourth flow channel 142, and compares whether the difference between T1 and T2 is greater than the set allowable temperature difference Ts. If the result is negative, the screening process continues. If the result is positive, indicating that the battery temperature difference is excessive and requires adjustment, the controller controls the reversing valve assembly 20 to switch the flow direction of the coolant to reduce the temperature difference between the battery cells at the second flow channel 132 and the fourth flow channel 142. The controller then continues to communicate with the BMS 300 to obtain the latest battery temperature, and the above process repeats.

[0047] After the controller controls the reversing valve group 20 to switch the working state, the reversing valve group 20 can feedback the switched working state to the controller so that the controller knows that the working state switch is completed. If the controller does not receive the feedback, it determines that the switch has failed and controls the reversing valve group 20 to switch the working state again.

[0048] In summary, the liquid cooling plate and battery pack provided in the embodiments of the present application, the liquid cooling plate includes a liquid cooling plate body and a reversing valve group. The liquid cooling plate body has a simple structure and is easy to design and manufacture. The reversing valve group changes the flow direction of the coolant in the liquid cooling plate body by switching the valve core, so that the low-temperature coolant cools the battery cells through which the high-temperature coolant that originally absorbs the heat of the battery cells flows, and the high-temperature coolant that absorbs the heat of the battery cells cools the battery cells through which the low-temperature coolant originally flows, which is equivalent to increasing the cooling effect on the high-temperature battery cells and reducing the cooling effect on the low-temperature battery cells, thereby effectively reducing the temperature difference of the battery cells in the battery pack and ensuring the consistency of the performance of the battery cells in the battery pack.

[0049] The above is only a specific implementation method of the present application, but the scope of protection of the present application is not limited thereto. Any technician familiar with the field can easily think of various changes or replacements within the technical scope disclosed in the present application, which should all be included in the scope of protection of the present application.

Claims

1. A liquid cooling plate, characterized in that: include: a liquid cooling plate body, wherein the liquid cooling plate body is provided with a first liquid inlet and outlet, a second liquid inlet and outlet, a first main channel, a second main channel, and a plurality of branch channels, wherein the first liquid inlet and outlet are connected to the first main channel, the second liquid inlet and outlet are connected to the second main channel, and the plurality of branch channels are arranged in parallel and connected between the first main channel and the second main channel; and The reversing valve group includes a valve body, a valve core, and a controller. One end of the valve body is connected to the first inlet and outlet and the second inlet and outlet, and the other end of the valve body is used to connect to the liquid cooling unit. The controller is used to control the switching of the valve core to change the flow direction of the coolant delivered by the liquid cooling unit in the liquid cooling plate body.

2. The liquid cooling plate according to claim 1, wherein: The first main channel includes a first flow channel portion and a second flow channel portion, the second main channel includes a third flow channel portion and a fourth flow channel portion, the first flow channel portion and the third flow channel portion extend opposite to each other along a first direction, two ends of the first flow channel portion are respectively connected to the first liquid inlet and outlet and the second flow channel portion, two ends of the third flow channel portion are respectively connected to the second liquid inlet and outlet and the fourth flow channel portion, the second flow channel portion and the fourth flow channel portion both extend along a second direction, and the first direction and the second direction are perpendicular to each other.

3. The liquid cooling plate according to claim 2, wherein: A plurality of the branch flow channels are arranged at equal intervals in the second direction between the second flow channel portion and the fourth flow channel portion. Each of the branch flow channels extends along the first direction and has two ends connected to the second flow channel portion and the fourth flow channel portion respectively.

4. The liquid cooling plate according to claim 2 or 3, characterized in that: The liquid cooling plate body is rectangular, having two side edges arranged along a first direction and another two side edges arranged along a second direction. The first liquid inlet and outlet and the second liquid inlet and outlet are arranged in the middle of one side edge of the liquid cooling plate body arranged along the first direction.

5. The liquid cooling plate according to claim 1, wherein: The valve body is provided with a first docking port, a second docking port, a valve group liquid inlet, and a valve group liquid outlet. The first docking port and the second docking port are connected to the first liquid inlet and outlet and the second liquid inlet and outlet respectively. The valve group liquid inlet and the valve group liquid outlet are used to connect to the liquid cooling unit.

6. The liquid cooling plate according to claim 5, characterized in that: The valve core includes a straight-through valve core and a reversing valve core.

7. The liquid cooling plate according to claim 6, wherein: The through valve core has a first valve core channel and a second valve core channel, the first valve core channel is used to connect the first docking port and the valve group liquid inlet, and the second valve core channel is used to connect the second docking port and the valve group liquid outlet; The reversing valve core has a third valve core channel and a fourth valve core channel. The third valve core channel is used to connect the second docking port and the valve group liquid inlet, and the fourth valve core channel is used to connect the first docking port and the valve group liquid outlet.

8. A battery pack, characterized in that: It comprises the liquid cooling plate according to any one of claims 1 to 7 and a plurality of battery cells, wherein the liquid cooling plate is in contact with the plurality of battery cells for cooling and dissipating heat.

9. The battery pack according to claim 8, characterized in that: It also includes a BMS battery management system, which is communicatively connected to the controller of the reversing valve group of the liquid cooling plate and the plurality of battery cells, and is used to detect the temperature of the plurality of battery cells and transmit it to the controller so that the controller can control the switching of the valve core accordingly.

10. The battery pack according to claim 9, characterized in that: The controller is used to control the switching of the valve core when the temperature difference of the battery core exceeds a set value.

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