Battery liquid-cooling device and battery pack

Abstract

Disclosed in the present application are a battery liquid-cooling device and a battery pack. The battery liquid-cooling device comprises a support frame, a first liquid-cooling body, and a second liquid-cooling body, wherein the first liquid-cooling body is disposed on the support frame, and is provided with a first channel; two ends of the second liquid-cooling body are respectively connected to the support frame and the first liquid-cooling body, and the second liquid-cooling body is provided with a second channel; the support frame, the first liquid-cooling body and the second liquid-cooling body define an accommodation cavity with an upward opening by means of enclosure; the accommodation cavity is configured to accommodate a battery cell; the strength of the first liquid-cooling body is greater than that of the second liquid-cooling body; both the first liquid-cooling body and the second liquid-cooling body are configured to support the battery cell accommodated in the accommodation cavity; when the battery cell is accommodated in the accommodation cavity, the area of an overlap between the projection of the battery cell in the vertical direction and the projection of the second liquid-cooling body in the vertical direction is greater than the area of an overlap between the projection of the battery cell in the vertical direction and the projection of the first liquid-cooling body in the vertical direction.

Description

Battery liquid cooling device and battery pack

[0001] The present application claims priority to the Chinese patent application No. 2024110955101 filed on August 9, 2024 with the China Patent Office, the content of which is incorporated herein by reference in its entirety. TECHNICAL FIELD

[0002] The present application relates to the technical field of battery manufacturing equipment, in particular to a battery liquid cooling device and a battery pack. BACKGROUND

[0003] CTP (Cell To Pack) technology is a kind of module-free battery pack structure technology, that is, the battery cell is directly integrated into the battery pack, and the traditional battery module is saved. This structure makes the battery pack can be directly integrated into the vehicle floor as part of the vehicle structure.

[0004] At present, CTP technology has become the mainstream design of battery pack. For square battery cells, the related technology adopts L-shaped tray side beam design as the support structure of the battery cell, which is combined with the square battery cell form to form a stable and reliable "simply supported beam" bearing structure. This structure not only ensures that the whole package mode can reach the high frequency vibration level of 50Hz, but also has high strength characteristics. TECHNICAL PROBLEM

[0005] However, other manufacturers usually adopt the scheme of the cell pole upward in the design of square battery cells, especially for small size square battery cells, due to structural limitations, usually only bottom liquid cooling method can be used. In this design, the battery cell is arranged at a position above the liquid cooling plate. When the whole package space is limited and cannot be equipped with transverse and longitudinal beams at the same time, the liquid cooling plate can only be used as a "floor", and the insufficient strength of the liquid cooling plate itself is revealed. This design limits the mechanical properties of the box. TECHNICAL SOLUTION

[0006] In a first aspect, the battery liquid cooling device comprises a support frame, a first liquid cooling body and a second liquid cooling body. The first liquid cooling body is arranged on the support frame and is provided with a first channel. The two ends of the second liquid cooling body are connected to the support frame and the first liquid cooling body respectively, and the second liquid cooling body is provided with a second channel. The support frame, the first liquid cooling body and the second liquid cooling body define a receiving cavity with an upward opening, and the receiving cavity is arranged to accommodate a battery cell. The first liquid cooling body and the second liquid cooling body are arranged to circulate cooling medium through the second channel and the first channel to cool the battery cell accommodated in the receiving cavity. The strength of the first liquid cooling body is greater than that of the second liquid cooling body. The first liquid cooling body and the second liquid cooling body are arranged to support the battery cell accommodated in the receiving cavity. When the battery cell is accommodated in the receiving cavity, the projection of the battery cell in the vertical direction overlaps with the projection of the second liquid cooling body in the vertical direction more than the projection of the battery cell in the vertical direction overlaps with the projection of the first liquid cooling body in the vertical direction.

[0007] In a second aspect, the battery pack comprises the battery liquid cooling device according to any one of the above. Advantages

[0008] The battery liquid cooling device provided by the technical scheme has the advantages that the first liquid cooling body with a greater strength than the second liquid cooling body can solve the problem of insufficient strength of the second liquid cooling body when the battery liquid cooling device is limited in space. The first liquid cooling body can provide sufficient support for the battery cell accommodated in the receiving cavity, thereby ensuring the overall mechanical performance of the battery liquid cooling device.

[0009] The first channel is arranged in the first liquid cooling body, and the second channel is arranged in the second liquid cooling body. The second channel and the first channel can be arranged to circulate cooling medium, thereby dissipating heat from the battery cell accommodated in the receiving cavity. The second liquid cooling body is mainly responsible for heat dissipation, while the first liquid cooling body can provide a small amount of heat dissipation while providing structural strength. The heat dissipation demand of the battery cell accommodated in the receiving cavity can be met, and the safety of the battery liquid cooling device is improved while ensuring the heat dissipation effect, thereby reducing the safety risk caused by insufficient strength of the second liquid cooling body. BRIEF DESCRIPTION OF DRAWINGS

[0010] FIG. 1 is an assembly diagram of the battery liquid cooling device according to an embodiment of the present application;

[0011] FIG. 2 is a structural diagram of the battery liquid cooling device according to an embodiment of the present application;

[0012] FIG. 3 is a structural diagram of the battery liquid cooling device according to an embodiment of the present application from another angle;

[0013] Fig. 4 is a sectional view along CC in Fig. 3;

[0014] Fig. 5 is an enlarged view of D in Fig. 4;

[0015] Fig. 6 is an exploded structural schematic view of the battery liquid cooling device in Fig. 2;

[0016] Fig. 7 is another exploded structural schematic view of the battery liquid cooling device in Fig. 2.

[0017] BRIEF DESCRIPTION OF THE DRAWINGS

[0018] 100, battery liquid cooling device; 10, support frame; 11, first stepped groove; 12, support cross beam; 13, support longitudinal beam; 14, bearing beam; 13a, liquid inlet; 13b, discharge port; 20, first liquid cooling body; 20a, first channel; 20b, return port; 20c, flow port; 21, second stepped groove; 30, second liquid cooling body; 30a, second channel; 30b, liquid outlet; 30c, liquid inlet; 40, return pipeline;

[0019] 200, battery cell.

[0020] Embodiments of the present application

[0021] CTP (Cell To Pack) technology is a kind of module-free battery pack structure technology, that is, the battery cell is directly integrated into the battery pack, and the traditional battery module is saved. This structure makes the battery pack can be directly integrated into the vehicle floor as part of the vehicle structure.

[0022] When facing the widely used cell pole-up layout and small size square cell of other manufacturers, the design limitation becomes particularly obvious. These designs usually only rely on the bottom liquid cooling scheme to arrange the battery cell above the liquid cooling plate. Although this method meets the heat dissipation demand to a certain extent, it also has some shortcomings.

[0023] Especially in the case where the whole pack space is limited and cannot accommodate the cross beam and longitudinal beam at the same time, the designer has to use the liquid cooling plate as a bearing "floor". Since the structural strength of the liquid cooling plate itself is not high, this design limits the mechanical performance of the whole battery pack.

[0024] Referring to Figs. 1-5, the battery liquid cooling device 100 provided by the embodiments of the present application includes a support frame 10, a first liquid cooling body 20 and a second liquid cooling body 30. It can be understood that the battery liquid cooling device 100 can be arranged in a battery pack, or it can be understood that the battery pack includes the battery liquid cooling device 100.

[0025] In the embodiment, the support frame 10 is made of aluminum alloy. The aluminum alloy support frame 10 is light in weight, has certain strength, and is easy to process into a required shape. The support frame 10 is a rectangular frame, which can provide a stable mounting space and facilitate arrangement of the square battery cells 200.

[0026] The first liquid cooling body 20 is arranged on the support frame 10. The first liquid cooling body 20 is an extrusion molding. The extrusion molding ensures that the first liquid cooling body 20 has a uniform wall thickness and stable mechanical properties. The wall thickness of the first liquid cooling body 20 is thicker than that of the second liquid cooling body 30, and the first liquid cooling body 20 is connected to the support frame 10 by welding, specifically, friction stir welding, which can improve the strength and corrosion resistance of the connection between the first liquid cooling body 20 and the support frame 10. Compared with the second liquid cooling body 30, the first liquid cooling body 20 has greater strength and is arranged to support the battery cells 200 accommodated in the accommodation cavity, so as to prevent the battery cells 200 from being deformed or damaged when subjected to external force, enhance the structural stability of the entire support frame 10, and help maintain the stable placement of the battery cells 200 in the support frame 10, thereby maintaining the performance even in a dynamic use environment. The first liquid cooling body 20 directly defines the first channel 20a for cooling medium flow through the extrusion molding cavity. The first channel 20a can be used in cooperation with the second channel 30a of the second liquid cooling body 30 to increase the flow path of the cooling medium and form a larger heat dissipation area.

[0027] The second liquid cooling body 30 is connected to the support frame 10 and the first liquid cooling body 20 at both ends, respectively. The second liquid cooling body 30 can be made of aluminum material with high thermal conductivity. The second liquid cooling body 30 is provided with a second channel 30a. The second liquid cooling body 30 dissipates heat from the battery cells 200 through the second channel 30a. The second channel 30a is arranged in a serpentine shape in the length direction of the second liquid cooling body 30 in the second liquid cooling body 30. Specifically, the second channel 30a can be formed by stamping inside the second liquid cooling body 30. The integral stamping molding can better form a complex channel shape. The serpentine-shaped second channel 30a can increase the heat dissipation area of the cooling medium, increase the flow path of the fluid in the channel, and improve the heat dissipation efficiency. In the embodiment, to match the support frame 10 in the form of a rectangular frame, the second liquid cooling body 30 includes a second liquid cooling plate and a heat-conducting structural adhesive arranged on the second liquid cooling plate. The second liquid cooling plate has a flat structure, and the larger side faces the side of the battery cells 200. In this way, the heat dissipation area is maximized without increasing the overall height of the battery liquid cooling device 100, and the space occupation in the height direction is reduced. The heat-conducting structural adhesive has good heat conductivity, which can conduct heat from the battery cells 200 to the second liquid cooling plate and improve the heat dissipation efficiency.

[0028] The support frame 10, the first liquid cooling body 20 and the second liquid cooling body 30 together define a receiving cavity with an upward opening, which is configured to receive the battery cell 200. The first liquid cooling body 20 and the second liquid cooling body 30 are configured to support the battery cell 200 received in the receiving cavity. The first liquid cooling body 20 and the second liquid cooling body 30 are configured to circulate the cooling medium through the second channel 30a and the first channel 20a to cool the battery cell 200 received in the receiving cavity.

[0029] When the battery cell 200 is received in the receiving cavity, the area of the projection of the battery cell 200 in the vertical direction that overlaps with the projection of the second liquid cooling body 30 in the vertical direction is greater than the area of the projection of the battery cell 200 in the vertical direction that overlaps with the projection of the first liquid cooling body 20 in the vertical direction. This arrangement ensures that the second liquid cooling body 30 can more effectively dissipate heat, while the first liquid cooling body 20 can assist in dissipating heat while providing support. By meeting the heat dissipation requirements of the battery cell 200, the provision of the first liquid cooling body 20 can improve the strength of the support for the battery cell 200, thereby improving the safety of the battery liquid cooling device 100 and reducing the safety risks caused by insufficient strength of the second liquid cooling body 30.

[0030] In actual use, the space enclosed by the support frame 10, the first liquid cooling body 20 and the second liquid cooling body 30 allows the battery cell 200 to be placed with the polar column facing upward (i.e., in a vertical position) or to be placed with the polar column facing left or right (i.e., in a horizontal position), and the present application does not limit this.

[0031] In some embodiments, the support frame 10 is provided with a first stepped groove 11, and the first liquid cooling body 20 is provided with a second stepped groove 21. The bottom surfaces of the first stepped groove 11 and the second stepped groove 21 are flush with each other, and the outer periphery of the second liquid cooling body 30 is embedded in the first stepped groove 11 and the second stepped groove 21, so that the second liquid cooling body 30 does not tilt after being embedded, and the displacement of the second liquid cooling body 30 caused by vibration or impact is reduced, thereby improving the overall safety of the battery liquid cooling device 100. The design of the first stepped groove 11 and the second stepped groove 21 enables the second liquid cooling body 30 to be stably connected to the support frame 10 and the first liquid cooling body 20, thereby enhancing the stability of the structure.

[0032] As shown in FIG. 6, in some embodiments, the second liquid cooling body 30 is provided with an outlet 30b, the outlet 30b is communicated with the second channel 30a, the first liquid cooling body 20 is provided with a return port 20b which is arranged adjacent to the outlet 30b, the return port 20b is communicated with the first channel 20a; the battery liquid cooling device 100 further comprises a return pipeline 40, two ends of the return pipeline 40 are connected with the outlet 30b and the return port 20b respectively, the flow direction of the cooling medium in the second channel 30a is different from the flow direction of the cooling medium in the first channel 20a. By arranging the outlet 30b and the return port 20b and the return pipeline 40, the cooling medium can be effectively circulated between the second liquid cooling body 30 and the first liquid cooling body 20, and the first channel 20a defined by the cavity of the first liquid cooling body 20 can be used as a return channel, thereby improving the heat dissipation efficiency of the whole battery pack.

[0033] The support frame 10 is provided with a supply port 13a and a discharge port 13b, the second liquid cooling body 30 is further provided with an inlet port 30c on the side opposite to the outlet 30b, the inlet port 30c is communicated with the supply port 13a; the first liquid cooling body 20 is further provided with an outlet port 20c on the side opposite to the return port 20b, the outlet port 20c is communicated with the discharge port 13b, the supply port 13a is arranged to input the cooling medium into the second liquid cooling body 30, and the discharge port 13b is arranged to discharge the cooling medium from the first liquid cooling body 20. The supply port 13a and the discharge port 13b are arranged on the same side of the support frame 10, which simplifies the layout of the cooling pipeline, reduces the complexity of the pipeline, and facilitates installation and maintenance.

[0034] Specifically, the outlet 30b and the inlet port 30c are arranged on the upper end face of the second liquid cooling body 30, the return port 20b and the outlet port 20c are arranged on the upper end face of the first liquid cooling body 20, the inlet port 30c is arranged adjacent to the supply port 13a to ensure that the cooling medium can smoothly enter the second liquid cooling body 30. The outlet port 20c is arranged adjacent to the discharge port 13b, so that the cooling medium can be discharged after completing the circulation. Since the input and output paths of the cooling medium are clear and direct, potential failure points are reduced, and the reliability of the whole cooling flow path is enhanced.

[0035] Understandably, in the present embodiment, the second channel 30a of the second liquid cooling body 30 is used as the inflow channel, and the first channel 20a of the first liquid cooling body 20 is used as the return channel, of course, the second channel 30a of the second liquid cooling body 30 can also be used as the return channel, and the first channel 20a of the first liquid cooling body 20 can be used as the inflow channel, which is not limited in the present application.

[0036] As shown in FIG. 7, in some embodiments, the support frame 10 includes two support cross beams 12 and two support longitudinal beams 13, a bearing beam 14, the two support longitudinal beams 13 are respectively connected to the opposite sides of the two support cross beams 12 to form a stable support structure. The bearing beam 14 is connected to the support cross beam 12, and the bearing beam 14 and the first liquid cooling body 20 are arranged to jointly support the two ends of the battery cell 200 accommodated in the accommodation cavity, which can significantly enhance the structural stability of the support frame 10, reduce the risk of damage to the battery cell 200 caused by vibration or impact, and improve the overall safety of the support frame 10. When the battery cell 200 is arranged in the accommodation cavity, the two ends of the battery cell 200 can be supported by the bearing beam 14 and the first liquid cooling body 20, respectively, more evenly dispersing the gravity of the battery cell 200, reducing the local pressure on the battery cell 200, and thereby reducing the risk of damage to the battery cell 200.

[0037] Among them, the bearing beam 14 is integrally formed with the support cross beam 12, which enhances the integrity of the support frame 10, reduces stress concentration at the connection, reduces the formation of fatigue cracks, thereby improving the durability of the support frame 10 and improving the structural integrity.

[0038] Specifically, the bearing beam 14 is located at the connection between the support cross beam 12 and the support longitudinal beam 13, and the bearing beam 14 works as an additional support structure together with the support cross beam 12 and the support longitudinal beam 13 to improve the stability of the entire support frame 10, which helps to reduce the space occupation inside the support frame 10, making the battery pack design more compact, and effectively bearing and dispersing the weight of the battery cell 200 and the external impact that may be received, reducing local stress concentration.

[0039] In some embodiments, the upper end faces of the bearing beam 14, the first liquid cooling body 20 and the second liquid cooling body 30 are at the same horizontal height. That is, the end faces of the bearing beam 14 and the first liquid cooling body 20 in contact with the battery cell 200 are flush along the height direction, ensuring that the bearing beam 14 and the first liquid cooling body 20 jointly support the two ends of the battery cell 200, ensuring that the two ends of the battery cell 200 are evenly stressed, avoiding deformation or damage of the battery cell 200 caused by uneven support, which can improve the rigidity of the entire battery liquid cooling device 100 and reduce the decline in bearing performance caused by structural deformation. The flush design also helps to simplify the installation process of the battery cell 200, ensuring that the battery cell 200 is correctly placed in the predetermined position and avoiding slipping in the accommodation cavity.

[0040] Referring to FIG. 2, in some embodiments, the carrying beams 14 and the first liquid cooling bodies 20 are arranged to extend along a first direction AA, the two carrying beams 14 are arranged to be opposite to each other along a second direction BB and are arranged in parallel and spaced apart, it can be understood that when the support frame 10 is a rectangular frame, the carrying beams 14 and the first liquid cooling bodies 20 are arranged to extend along the length direction of the support frame 10, the carrying beams 14 are arranged to be opposite to each other along the width direction of the support frame 10, and the carrying beams 14 are arranged to provide uniform support and reduce the vibration influence of the battery cells 200 in the vertical direction. The second liquid cooling bodies 30 are arranged to be multiple, which can better absorb the heat generated by the battery cells 200 and dissipate the heat through the second liquid cooling bodies 30, thereby improving the heat dissipation performance of the entire battery pack, and a first liquid cooling body 20 is arranged between two adjacent second liquid cooling bodies 30, that is, the second liquid cooling bodies are in abutment with the first liquid cooling bodies on both sides of the width direction of the support frame 10, the first liquid cooling bodies are in abutment with the carrying beams 14, and the arrangement of the carrying beams 14, the second liquid cooling bodies 30 and the first liquid cooling bodies 20 makes full use of the space of the support frame 10, allowing the first liquid cooling bodies 20 to provide additional support and heat dissipation for the battery cells 200 while maintaining the compactness of the battery liquid cooling device 100, wherein the first direction AA is perpendicular to the second direction BB.

[0041] It can be understood that the length and width of the support frame 10 can be increased according to actual use, and the number of first liquid cooling bodies can be adjusted to adapt to different sizes and shapes of the support frame 10 design and accommodate more battery cells 200.

[0042] In some embodiments, the first liquid cooling body 20 is further provided with an intermediate rib, which separates the cavity into a first cavity and a second cavity, and the intermediate rib can strengthen the strength of the first liquid cooling body 20 and improve its stability when bearing external load. The first cavity can be used in cooperation with the second channel 30a of the second liquid cooling body 30 on the opposite side, and the second cavity can also be used in cooperation with the second channel 30a of another second liquid cooling body 30 on the opposite side.

[0043] Specifically, the plurality of liquid inlets 30c corresponding to the plurality of second liquid cooling bodies 30 are all communicated with the liquid supply port 13a, and correspondingly, if a plurality of first liquid cooling bodies 20 are arranged, the plurality of liquid outlets 20c corresponding to the plurality of first liquid cooling bodies 20 are all communicated with the discharge port 13b. Since the same liquid supply port 13a and discharge port 13b are shared, only one connection point needs to be handled when maintenance and replacement are required, which reduces the difficulty of maintenance, simplifies the pipeline layout of the cooling flow path, ensures the orderly flow and effective heat dissipation of the cooling medium, and reduces the pipeline connection points, thereby reducing the risk of pipeline blockage and leakage.

[0044] In some embodiments, the first liquid cooling body 20 has a width greater than twice the width of the carrying beam 14, and one carrying beam 14 is arranged to carry a plurality of battery cells 200 arranged in the first direction AA, allowing the battery cells 200 to be closely arranged in the longitudinal direction while being uniformly supported by the carrying beam 14. The first liquid cooling body 20 is arranged to carry two groups of battery cells 200 arranged in the second direction BB. By increasing the width of the first liquid cooling body 20, sufficient heat dissipation surface can be provided for the two groups of battery cells 200 in the transverse direction while maintaining the compactness of the battery liquid cooling device 100.

[0045] In some embodiments, the first liquid cooling body 20 is arranged in parallel and spaced apart from the carrying beam 14, and the second liquid cooling body 30 is located between the carrying beam 14 and the first liquid cooling body 20. The second liquid cooling body 30 is provided with two blocks, and the first liquid cooling body 20 is located at the middle position of the two carrying beams 14 along the second direction BB, providing uniform cooling effect for the two groups of battery cells 200 supported by the first liquid cooling body 20, enhancing the heat dissipation effect.

[0046] In some embodiments, the second liquid cooling body 30 constitutes about 90% of the cavity bottom area of the accommodation cavity, ensuring sufficient heat dissipation of the main area of the battery cell 200, and the first liquid cooling body 20 constitutes about 10% of the cavity bottom area of the accommodation cavity, making the battery liquid cooling device 100 compact in structure and not occupying too much space. This area allocation ensures maximum heat dissipation efficiency in limited space while maintaining the compactness of the structure and the stability of the battery cell 200.

Claims

1. A battery liquid cooling device, comprising: a support frame; a first liquid cooling body arranged on the support frame, the first liquid cooling body being provided with a first channel; and a second liquid cooling body connected to the support frame and the first liquid cooling body at two ends respectively, the second liquid cooling body being provided with a second channel, the support frame, the first liquid cooling body and the second liquid cooling body defining a receiving cavity with an upward opening, the receiving cavity being configured to receive a battery cell; the first liquid cooling body and the second liquid cooling body being configured to circulate a cooling medium through the second channel and the first channel to cool the battery cell received in the receiving cavity; wherein the strength of the first liquid cooling body is greater than the strength of the second liquid cooling body, and the first liquid cooling body and the second liquid cooling body are both configured to support the battery cell received in the receiving cavity; when the battery cell is received in the receiving cavity, the projection of the battery cell in a vertical direction overlaps with the projection of the second liquid cooling body in the vertical direction more than the projection of the battery cell in the vertical direction overlaps with the projection of the first liquid cooling body in the vertical direction. the support frame is provided with a first stepped groove, the first liquid cooling body is provided with a second stepped groove, and the groove bottom surfaces of the first stepped groove and the second stepped groove are flush; 2. The battery liquid cooling apparatus according to claim 1, wherein the outer periphery of the second liquid cooling body is embedded in the first stepped groove and the second stepped groove. the support frame comprises:

3. The battery liquid cooling apparatus according to claim 2, wherein two support cross beams and two support longitudinal beams, the two support longitudinal beams being connected to opposite sides of the two support cross beams respectively; a load bearing beam connected to the support cross beam, the load bearing beam and the first liquid cooling body being configured to jointly support the battery cell received in the receiving cavity. the upper end surfaces of the load bearing beam, the first liquid cooling body and the second liquid cooling body are all located at the same horizontal height.

4. The battery liquid cooling apparatus according to claim 3, wherein the load bearing beam and the first liquid cooling body are both arranged in a first direction, the load bearing beam is provided in two, the two load bearing beams are oppositely arranged in a second direction, the second liquid cooling body is provided in multiple, one first liquid cooling body is arranged between two adjacent second liquid cooling bodies, and the first direction is perpendicular to the second direction.

5. The battery liquid cooling apparatus according to any one of claims 3 to 4, wherein the width of the first liquid cooling body is greater than twice the width of the load bearing beam, one load bearing beam is configured to bear a plurality of battery cells arranged in the first direction, and one first liquid cooling body is configured to bear two groups of battery cells arranged in the second direction.

6. The battery liquid cooling apparatus according to claim 5, wherein the first liquid cooling body and the load bearing beam are arranged in parallel and at intervals, the second liquid cooling body is located between the load bearing beam and the first liquid cooling body, the second liquid cooling body is provided in two, and the first liquid cooling body is located at the middle position of the two load bearing beams in the second direction; 7. The battery liquid cooling apparatus according to claim 6, wherein wherein the first liquid cooling body accounts for about 10% of the cavity bottom area of the receiving cavity, and the second liquid cooling body accounts for about 90% of the cavity bottom area of the receiving cavity. the first liquid cooling body is an extrusion molding; and / or 8. The battery liquid cooling apparatus according to claim 1, wherein the first liquid cooling body is welded to the support frame; and / or the second channel is formed by stamping inside the second liquid cooling body. ​ 9. The battery liquid cooling apparatus according to claim 1, wherein The second liquid cooling body is provided with a liquid outlet, the liquid outlet is communicated with the second channel, the first liquid cooling body is provided with a backflow port arranged adjacent to the liquid outlet, and the backflow port is communicated with the first channel; The battery liquid cooling device further comprises a backflow pipeline, two ends of the backflow pipeline are connected with the liquid outlet and the backflow port respectively, and the flow direction of the cooling medium in the second channel is different from the flow direction of the cooling medium in the first channel. 10.A battery pack comprising the battery liquid cooling device according to any one of claims 1 to 9.

Images