Liquid cooling assembly and battery pack

Abstract

The utility model provides a liquid cooling assembly and a battery pack, relates to the technical field of batteries, and is used for solving the technical problem that temperature difference exists between the edge position and the middle position of a current battery pack, and the liquid cooling assembly comprises a liquid cooling plate and a pipeline assembly; the liquid cooling plate comprises a heat exchange cavity, and a first communication port and two second communication ports which are communicated with the heat exchange cavity; the first communicating port is located in the middle of the circulating flow channel, and the two second communicating ports are formed in the two ends of the circulating flow channel correspondingly. The pipeline assembly comprises a reversing valve, and an injection pipeline and a lead-out pipeline which are communicated with the reversing valve, and when the reversing valve is configured to be in a first state, the injection pipeline is communicated with the first communication port, and the lead-out pipeline is communicated with the second communication port; and when the reversing valve is in a second state, the injection pipeline is communicated with the second communication port, and the lead-out pipeline is communicated with the first communication port. The liquid cooling assembly provided by the utility model is used for performing thermal management on the battery pack, and the temperature difference of the battery pack can be reduced.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a liquid cooling assembly and a battery pack. Background Art

[0002] In recent years, electric vehicles have developed rapidly, and battery packs have become a hot topic of research. As the power output of electric vehicles, lithium-ion battery packs have strict temperature requirements, so battery packs must be equipped with liquid cooling plates to effectively help heat and cool the battery packs to ensure their normal operation.

[0003] The current battery pack includes a box, a liquid cooling plate and a battery module, wherein the liquid cooling plate is the core component, which is usually arranged at the bottom of the box and below the battery module to facilitate heating and cooling of the battery module. The liquid cooling plate is arranged with a flow channel, and its flow channel form is too simple. The flow direction of the fluid in the flow channel is fixed, and the fluid inlet is fixed at the same position, or enters from the middle and exits from both sides, or enters from both sides and exits from the middle.

[0004] However, when the above-mentioned liquid cooling plate is used to perform thermal management on the entire battery pack, there is a temperature difference between the edge and the middle of the battery pack, which affects the charging and discharging performance, safety and service life of the battery pack. Utility Model Content

[0005] In view of the above problems, the embodiments of the present application provide a liquid cooling assembly and a battery pack, which can reduce the temperature difference of the battery pack and improve the charging and discharging performance, life and safety of the battery pack.

[0006] In order to achieve the above objectives, the embodiments of the present application provide the following technical solutions:

[0007] A first aspect of an embodiment of the present application provides a liquid cooling assembly for thermal management of a battery pack, the liquid cooling assembly comprising a liquid cooling plate and a piping assembly; the liquid cooling plate comprising a heat exchange chamber and a first connecting port and two second connecting ports connected to the heat exchange chamber; the heat exchange chamber is provided with a circulation channel, the first connecting port is located in the middle position of the circulation channel, and the two second connecting ports are respectively arranged at both ends of the circulation channel; the piping assembly comprises a reversing valve and an injection pipeline and an outlet pipeline connected to the reversing valve, the reversing valve is configured so that when it is in a first state, the injection pipeline is connected to the first connecting port, and the outlet pipeline is connected to the second connecting port; and when the reversing valve is in a second state, the injection pipeline is connected to the second connecting port, and the outlet pipeline is connected to the first connecting port.

[0008] In an optional embodiment, the liquid cooling plate includes a plurality of partitions; the plurality of partitions are arranged in the heat exchange chamber at intervals along a first direction, two adjacent partitions form a flow channel, and the plurality of flow channels are connected end to end to form the circulation flow channel; along the first direction, the two flow channels located in the middle position have a connecting area, and the first connecting port is connected to the connecting area.

[0009] In an optional embodiment, the reversing valve includes a valve assembly and a liquid inlet, a first liquid outlet, a second liquid outlet and a third liquid outlet that are interconnected; the liquid inlet is connected to the injection pipeline, and the first liquid outlet is connected to the outlet pipeline; the second liquid outlet is connected to the first connecting port, and the third liquid outlet is connected to the two second connecting ports respectively; the valve assembly is configured to control the liquid inlet to selectively connect to the second liquid outlet or the third liquid outlet.

[0010] In an optional embodiment, the reversing valve includes a valve body and a first channel, a second channel, a first connecting channel and a second connecting channel arranged in the valve body; the liquid inlet and the third liquid outlet are respectively located at two ends of the first channel, and the first liquid outlet and the second liquid outlet are respectively located at two ends of the second channel; the valve assembly includes a first valve, a second valve, a third valve and a fourth valve; the first valve is arranged in the first channel, the second valve is arranged in the first connecting channel, the third valve is arranged in the second channel, and the fourth valve is arranged in the second connecting channel.

[0011] In an optional embodiment, the pipeline assembly further includes a first pipeline and a second pipeline; the first pipeline is used to connect the second liquid outlet with the first connecting port, and the second pipeline is used to connect the third liquid outlet with the two second connecting ports.

[0012] In an optional embodiment, the second pipeline includes two connected branches; one end of the two branches is respectively connected to the second connecting port, and the other end of the two branches is respectively connected to the third liquid outlet.

[0013] A second aspect of an embodiment of the present application provides a battery pack, comprising a battery box, at least one battery cell module and the liquid cooling assembly described in the first aspect; the liquid cooling assembly is arranged at the bottom of the battery box, the battery cell module is arranged in the battery box and is located on the liquid cooling plate of the liquid cooling assembly.

[0014] In an optional embodiment, the liquid cooling assembly includes a reversing valve and an injection pipeline and an outlet pipeline connected to the reversing valve; the injection pipeline, the outlet pipeline and the reversing valve are located outside the battery box.

[0015] In an optional embodiment, a thermally conductive adhesive layer is provided between the battery cell module and the liquid cooling plate; the battery cell module includes a plurality of battery cells, the plurality of battery cells are arranged into two rows of battery cell groups, and an isolation plate is provided between two adjacent battery cell groups.

[0016] In an optional embodiment, end plates are respectively provided at both ends of the battery cell module, and a heat insulation plate is provided between the end plates and the battery cells.

[0017] Compared with the related art, the liquid cooling assembly and battery pack provided in the embodiments of the present application have the following advantages:

[0018] The liquid cooling assembly and battery pack provided in the embodiments of the present application, wherein the liquid cooling assembly is provided with a reversing valve between an injection line, an outlet line, and a liquid cooling plate, and second connecting ports are provided at both ends of a circulation channel of the liquid cooling plate, and a first connecting port is provided in the middle position of the circulation channel.

[0019] The reversing valve is controlled to be reversing, so that when it is in the first state, the injection pipeline is connected with the first connecting port, and the outlet pipeline is connected with the second connecting port, at which time the liquid enters from the first connecting port located in the middle of the liquid cooling plate and flows out from the second connecting ports located on both sides of the liquid cooling plate. When the reversing valve is in the second state, the injection pipeline is connected with the second connecting port, and the outlet pipeline is connected with the first connecting port, so that the liquid is injected from the second connecting ports located on both sides of the liquid cooling plate and flows out from the first connecting port located in the middle of the liquid cooling plate.

[0020] Furthermore, when the battery pack is in a high temperature environment, the reversing valve is in the first state, and the low-temperature fluid flows in from the middle of the liquid cooling plate, first lowering the temperature of the middle battery cell of the battery pack, and then flows out from the two side edges of the liquid cooling plate, so that the temperature difference between the middle position and the two side positions of the entire battery pack is small.

[0021] When the battery pack is in a low-temperature environment, the reversing valve is in the second state. At this time, the flow direction of the liquid is just opposite. The high-temperature fluid flows in from the two side edges of the liquid cooling plate, first raising the temperature of the edge cells of the battery pack, and then flows out from the middle of the liquid cooling plate, which can reduce the temperature difference between the middle position and the two side edge positions of the entire battery pack.

[0022] In the related art, the flow channel form in the liquid cooling plate is too simple, the flow direction of the fluid in the flow channel is fixed, the fluid inlet is fixed at the same position, or the fluid enters from the middle and exits from both sides, or enters from both sides and exits from the middle. It is impossible to adjust the flow direction of the liquid in the flow channel according to the environment in which the battery pack is located.

[0023] For example, if the fluid flows in from the middle of the liquid cooling plate and flows out from the edges on both sides, in a low-temperature environment, the high-temperature fluid will first flow through the middle of the battery pack, heating the cells in the middle first, and the edge cells with higher heat transfer strength to the outside world will be heated last, resulting in uneven temperature distribution of the entire battery pack and a large temperature difference. Similarly, if the fluid flows in from the edges of the liquid cooling plate and flows out from the middle, the temperature difference of the entire battery pack will also be large in a high-temperature environment, ultimately affecting the charging and discharging performance, safety and life of the battery pack.

[0024] However, the liquid cooling assembly provided in the implementation of the present application can adjust the flow direction of the liquid in the circulation channel through the reversing valve according to the environment in which the battery pack is located, so as to reduce the temperature difference between the middle position and the two sides of the entire battery pack, thereby improving the charging and discharging performance, safety and service life of the battery pack.

[0025] In addition to the technical problems solved by the embodiments of the present disclosure, the technical features that constitute the technical solutions, and the beneficial effects brought about by the technical features of these technical solutions described above, other technical problems that can be solved by the liquid cooling assembly and battery pack provided by the embodiments of the present disclosure, other technical features included in the technical solutions, and the beneficial effects brought about by these technical features will be further described in detail in the specific implementation methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0027] Figure 1 An exploded schematic diagram of a battery pack provided in an embodiment of the present application;

[0028] Figure 2 A schematic diagram of the structure of a liquid cooling assembly provided in an embodiment of the present application;

[0029] Figure 3 A schematic diagram of the arrangement of the circulation channel provided in the embodiment of the present application;

[0030] Figure 4 A schematic diagram of the structure of the reversing valve provided in an embodiment of the present application;

[0031] Figure 5 A schematic diagram of the flow of liquid in a circulation channel when the reversing valve provided in an embodiment of the present application is in a first state;

[0032] Figure 6A schematic diagram of the states of various valve components when the reversing valve provided in an embodiment of the present application is in a first state;

[0033] Figure 7 A schematic diagram of the flow of liquid in the circulation channel when the reversing valve provided in the embodiment of the present application is in the second state;

[0034] Figure 8 A schematic diagram of the states of each valve component when the reversing valve provided in an embodiment of the present application is in a second state;

[0035] Fig. 9 A schematic diagram of the structure of the battery cell module provided in an embodiment of the present application.

[0036] Description of reference numerals:

[0037] 10-battery box;

[0038] 11-box body; 12-box cover; 13-crossbeam;

[0039] 20-battery cell module;

[0040] 21-battery core; 22-end plate; 23-heat insulation board; 24-isolation board;

[0041] 30-Liquid cooling assembly;

[0042] 31-injection pipeline; 32-export pipeline;

[0043] 33- reversing valve;

[0044] 301-valve body; 302-first channel; 303-second channel; 304-first communication channel; 305-second communication channel;

[0045] 331 - liquid inlet; 332 - first liquid outlet; 333 - second liquid outlet; 334 - third liquid outlet; 335 - first valve; 336 - second valve; 337 - third valve; 338 - fourth valve;

[0046] 34-first pipeline; 35-second pipeline; 36-liquid cooling plate; 361-first connecting port; 362-second connecting port; 363-circulating flow channel; 3631-connecting area; 364-partition;

[0047] 40-thermal conductive adhesive layer;

[0048] 100-battery pack. DETAILED DESCRIPTION

[0049] As described in the background technology, there is a temperature difference between the middle and edge positions of the current battery pack, which affects the charging and discharging performance, safety and service life of the battery pack. The inventors have found that the reason for this problem is that the flow channel form of the liquid cooling plate of the current battery pack is too single, the flow direction of the fluid in the flow channel is fixed, and the fluid inlet is fixed at the same position, or the solution is in the middle and out on both sides, or in the two sides and out of the middle. The flow direction of the liquid in the flow channel cannot be adjusted according to the environment in which the battery pack is located, resulting in a temperature difference between the middle and edge positions of the battery pack.

[0050] In response to the above technical problems, an embodiment of the present application provides a new liquid cooling component, in which a reversing valve is arranged between the injection pipeline, the outlet pipeline, and the liquid cooling plate, and a second connecting port is arranged at both ends of the circulation channel of the liquid cooling plate, and a first connecting port is arranged in the middle position of the circulation channel.

[0051] When the battery pack is in a high temperature environment, the reversing valve is controlled to be in the first state, at which time the injection pipeline is connected to the first connection port, and the outlet pipeline is connected to the second connection port. The low-temperature fluid flows in from the middle of the liquid cooling plate, first lowering the temperature of the battery cell in the middle, and then flows out from the two side edges of the liquid cooling plate, so that the temperature difference between the middle and the two side edges of the entire battery pack is small.

[0052] When the battery pack is in a low temperature environment, the reversing valve is in the second state, the injection pipeline is connected to the second connection port, and the outlet pipeline is connected to the first connection port. The high-temperature fluid flows in from the edges of the liquid cooling plate, first raising the temperature of the edge cells of the battery pack, and then flows out from the middle position of the liquid cooling plate, so that the temperature difference between the middle position and the two sides of the entire battery pack is small.

[0053] With such a configuration, the liquid cooling assembly provided by the present application can adjust the flow direction of the liquid in the circulation channel through the reversing valve according to the environment in which the battery pack is located, so as to reduce the temperature difference between the middle position and the two sides of the entire battery pack, thereby improving the charging and discharging performance, safety and service life of the battery pack.

[0054] In order to make the above-mentioned purposes, features and advantages of the embodiments of the present application more obvious and understandable, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work belong to the scope of protection of this application.

[0055] To facilitate the description of the embodiments of the present application, the coordinate system in the accompanying drawings is first explained. The X-axis direction in the coordinate system is a first direction, which may be a width direction of the battery pack; the Y-axis direction is a second direction, which may be a length direction of the battery pack; and the Z-axis direction is a third direction, which may be a height direction of the battery pack.

[0056] like Figure 1 As shown, the battery pack 100 provided in the embodiment of the present application includes at least one battery cell module 20, a battery box 10 and a liquid cooling assembly 30. The battery box 10 includes a box body 11 and a box cover 12. Along the third direction, the box cover 12 is covered on the box body 11 to form an accommodation space. The accommodation space is used to install the liquid cooling assembly 30 and the battery cell module 20. The liquid cooling assembly 30 and the battery cell module 20 are sequentially arranged at the bottom of the box body 11, and the battery cell module 20 is arranged on the liquid cooling assembly 30.

[0057] For example, in the embodiment of the present application, the battery pack 100 includes a plurality of battery cell modules 20, and the plurality of battery cell modules 20 can be arranged in an array in the accommodation space. The bottom of the battery cell module 20 contacts the surface of the liquid cooling assembly 30, and the liquid cooling assembly 30 is connected to the refrigeration assembly or the heating assembly to introduce liquid into the liquid cooling plate 36, so that the liquid cooling plate 36 can perform heat exchange with the battery cell module 20.

[0058] For example, in a low-temperature environment, the liquid cooling component 30 heats the battery cell module 20 based on high-temperature liquid, and in a high-temperature environment, the liquid cooling component 30 can cool the battery cell module 20 based on low-temperature liquid to achieve thermal management of the battery pack 100 .

[0059] like Figure 2 As shown, the liquid cooling assembly 30 provided in the embodiment of the present application is used for thermal management of the battery cell module 20. The liquid cooling assembly 30 includes a liquid cooling plate 36 and a pipeline assembly, wherein the above-mentioned multiple battery cell modules 20 are arranged on the liquid cooling plate 36 and contact the upper surface of the liquid cooling plate 36, so as to perform heat exchange with each battery cell 21 of the battery cell module 20 through the liquid cooling plate 36.

[0060] The liquid cooling plate 36 serves as a "heat exchanger", which includes a heat exchange cavity and a first communication port 361 and two second communication ports 362 communicating with the heat exchange cavity. Along the first direction, the first communication port 361 can be arranged in the middle of the liquid cooling plate 36, and the two second communication ports 362 can be arranged respectively on both sides of the liquid cooling plate 36. Further, along the second direction, the first communication port 361 and the two second communication ports 362 can be arranged at the same end of the liquid cooling plate 36 and close to the pipeline assembly.

[0061] For example, the liquid cooling plate 36 includes a first end and a second end that are oppositely arranged along the second direction, the first end may be the left end of the liquid cooling plate 36, and the second end may be the right end of the liquid cooling plate 36, and the first communication port 361 and the two second communication ports 362 are respectively arranged at the left end of the liquid cooling plate 36. Along the third direction, the first communication port 361 and the two second communication ports 362 are both arranged at the top of the liquid cooling plate 36, and are respectively connected to the heat exchange cavity.

[0062] like Figure 3 As shown, a circulation channel 363 is provided in the heat exchange cavity, and along the first direction, the first connecting port 361 is located in the middle of the circulation channel 363, and the two second connecting ports 362 are respectively provided at both ends of the circulation channel 363. For example, after the liquid flows into the heat exchange cavity from the first connecting port 361, it can flow to both sides of the heat exchange cavity along the circulation channel 363, and further flow out of the heat exchange cavity from the two second connecting ports 362. Also, after the liquid flows into the heat exchange cavity from the two second connecting ports 362, it can flow to the middle of the heat exchange cavity along the circulation channel 363, and flow out of the heat exchange cavity from the first connecting port 361.

[0063] In the embodiment of the present application, the pipeline assembly includes an injection pipeline 31, an outlet pipeline 32 and a reversing valve 33, wherein the injection pipeline 31 and the outlet pipeline 32 are respectively connected to the reversing valve 33, and the reversing valve 33 adjusts the flow direction of the liquid in the circulation channel 363 according to the environment in which the battery pack 100 is located.

[0064] For example, see Figure 5 and Figure 6 When the battery pack 100 is in a high temperature environment, the reversing valve 33 is controlled to be reversed so that the reversing valve 33 is in the first state. At this time, the injection pipeline 31 is connected to the first connecting port 361, and the outlet pipeline 32 is connected to the two second connecting ports 362 respectively. At this time, the low-temperature fluid flows in from the middle position of the liquid cooling plate 36, first lowers the temperature of the battery cell in the middle position, and then flows out from the edges on both sides of the liquid cooling plate 36, so that the temperature difference between the middle position and the two sides of the entire battery pack 100 is small.

[0065] See also Figure 7 and Figure 8 When the battery pack 100 is in a low temperature environment, the reversing valve 33 is controlled to be reversed so that the reversing valve 33 is in the second state. At this time, the injection pipeline 31 is connected to the two second connecting ports 362 respectively, and the outlet pipeline 32 is connected to the first connecting port 361; the high-temperature fluid flows into the liquid cooling plate 36 from the edges on both sides of the liquid cooling plate 36, first raising the temperature of the battery cells located at the edge positions on both sides, and then flows out from the middle of the liquid cooling plate 36, so that the temperature difference between the middle position and the two side positions of the entire battery pack 100 is small.

[0066] In the related art, the flow channel form in the liquid cooling plate is too simple, the flow direction of the fluid in the flow channel is fixed, the fluid inlet is fixed at the same position, or the fluid enters from the middle and exits from both sides, or enters from both sides and exits from the middle. It is impossible to adjust the flow direction of the liquid in the flow channel according to the power environment.

[0067] For example, if the fluid flows in from the middle of the liquid cooling plate and flows out from the edges on both sides, in a low-temperature environment, the high-temperature fluid will first flow through the middle of the battery pack, heating the middle battery cells first, and the edge batteries with higher heat transfer strength to the outside world will be heated last, resulting in uneven temperature distribution of the entire battery pack and a large temperature difference. Similarly, if the fluid flows in from the edges of the liquid cooling plate and flows out from the middle, then in a high-temperature environment, the temperature difference of the entire battery pack will also be large, ultimately affecting the charging and discharging performance, safety and life of the battery pack.

[0068] However, the liquid cooling assembly 30 provided in the implementation of the present application can adjust the flow direction of the liquid in the circulation channel 363 through the reversing valve 33 according to the environment in which the battery pack 100 is located, so as to reduce the temperature difference between the middle position and the two side positions of the entire battery pack 100, thereby improving the charging and discharging performance, safety and service life of the battery pack 100.

[0069] Based on the above embodiments, Figure 3 As shown, in the embodiment of the present application, the liquid cooling plate 36 includes a plurality of partitions 364, and the plurality of partitions 364 are arranged in the heat exchange chamber at intervals along a first direction. Each partition 364 extends along a second direction, and a flow channel is formed between two adjacent partitions 364. Furthermore, two adjacent flow channels are connected end to end to form a circulation flow channel 363.

[0070] The two flow channels located in the middle along the first direction have a communication area 3631, and the first communication port 361 is connected to the communication area 3631, so that the liquid entering from the first communication port 361 can flow into the flow channels on both sides at the same time, and further flow to the second communication ports 362 located at both ends of the circulation flow channel 363. Accordingly, the liquid entering from the second communication port 362 flows into the circulation flow channel 363, and further flows to the communication area 3631 and the first communication port 361.

[0071] like Figure 4 As shown, the reversing valve 33 provided in the embodiment of the present application includes a valve assembly and a liquid inlet 331, a first liquid outlet 332, a second liquid outlet 333 and a third liquid outlet 334 that are interconnected, wherein the liquid inlet 331 is connected to the injection pipeline 31, the first liquid outlet 332 is connected to the outlet pipeline 32, the second liquid outlet 333 is connected to the first connecting port 361, and the third liquid outlet 334 is connected to the two second connecting ports 362 respectively.

[0072] Further, the valve assembly is configured to control the liquid inlet 331 to selectively communicate with the second liquid outlet 333 or the third liquid outlet 334. Figure 5 and Figure 6 As shown, when the reversing valve 33 is in the first state, the liquid inlet 331 is connected with the second liquid outlet 333, so that the liquid flowing in through the injection pipeline 31 enters the middle position of the liquid cooling plate 36 through the liquid inlet 331, the second liquid outlet 333 and the first communication port 361. At this time, the third liquid outlet 334 is connected with the first liquid outlet 332, so that the liquid flowing out from the two second communication ports 362 is discharged through the discharge pipeline 32.

[0073] like Figure 7 and Figure 8 As shown, when the reversing valve 33 is in the second state, the liquid inlet 331 is connected with the third liquid outlet 334, so that the liquid flowing in through the injection pipeline 31 flows into the two side edges of the liquid cooling plate 36 through the liquid inlet 331, the third liquid outlet 334, and the two second connecting ports 362; at this time, the first liquid outlet 332 is connected with the second liquid outlet 333, so that the liquid flowing out of the first connecting port 361 is discharged through the outlet pipeline 32.

[0074] On the basis of the above-mentioned embodiments, the reversing valve 33 in the embodiment of the present application includes a valve body 301 and a first channel 302, a second channel 303, a first connecting channel 304 and a second connecting channel 305 arranged in the valve body 301; wherein the first channel 302 and the second channel 303 are arranged in parallel along the second direction, and there is a gap between them along the first direction, and they are connected through the first connecting channel 304 and the second connecting channel 305.

[0075] For example, the first communication channel 304 and the second communication channel 305 extend in the first direction, and both ends are respectively connected to the first channel 302 and the second channel 303. In the second direction, the liquid inlet 331 and the third liquid outlet 334 are respectively located at both ends of the first channel 302, that is, the liquid inlet 331 and the third liquid outlet 334 are connected through the first channel 302; in the second direction, the first liquid outlet 332 and the second liquid outlet 333 are respectively located at both ends of the second channel 303, that is, the first liquid outlet 332 and the second liquid outlet 333 are connected through the second channel 303.

[0076] The valve assembly includes a first valve 335, a second valve 336, a third valve 337 and a fourth valve 338; the first valve 335 is arranged in the first channel 302, and the first valve 335 controls the connection between the liquid inlet 331 and the third liquid outlet 334; the second valve 336 is arranged in the first connecting channel 304, and the second valve 336 controls the opening and closing of the first connecting channel 304; the third valve 337 is arranged in the second channel 303, and the third valve 337 controls the connection between the first liquid outlet 332 and the second liquid outlet 333; the fourth valve 338 is arranged in the second connecting channel 305, and the fourth valve 338 controls the opening and closing of the second connecting channel 305.

[0077] Furthermore, the pipeline assembly in the embodiment of the present application further includes a first pipeline 34 and a second pipeline 35; wherein the first pipeline 34 is used to connect the second liquid outlet 333 with the first communication port 361; and the second pipeline 35 is used to connect the third liquid outlet 334 with the two second communication ports 362. For example, the second pipeline 35 includes two connected branches, the two branches are connected in parallel, and one end of each branch is respectively connected to the second communication port 362, and the other end of each branch is collected and connected to the third liquid outlet 334.

[0078] It should be noted that in the embodiment of the present application, the injection pipeline 31, the outlet pipeline 32 and the reversing valve 33 can be arranged outside the battery box 10, and the first pipeline 34 and the second pipeline 35 are penetrated into the box body 11 and connected with the first connecting port 361 and the second connecting port 362 of the liquid cooling plate 36.

[0079] For example, the battery box 10 includes a box body 11, a liquid cooling plate 36 is arranged in the box body 11, and along the second direction, the first connecting port 361 and the second connecting port 362 are respectively located at the left end of the liquid cooling plate 36, then the reversing valve 33 is arranged close to the left end of the box body 11 and is located on the outside of the box body 11.

[0080] Furthermore, the injection pipeline 31 and the outlet pipeline 32 can be arranged on the side of the reversing valve 33 away from the box 11. For example, the injection pipeline 31 and the outlet pipeline 32 are arranged on the left side of the reversing valve 33. One end of the first pipeline 34 and the second pipeline 35 is connected to the reversing valve 33, and the other end needs to pass through the box 11 and be connected to the liquid cooling plate 36 in the box 11.

[0081] Based on the above liquid cooling assembly 30, the flow direction of the liquid in the pipeline assembly under different states of the reversing valve 33 when the battery pack 100 is in a high temperature environment and a low temperature environment is described in detail:

[0082] In a high temperature environment, a large amount of heat is generated when the battery cell 21 is charged and discharged. If this heat cannot be removed in time, it will accumulate inside the entire battery pack 100, causing the temperature of the battery cell 21 inside the battery pack 100 to rise to a higher level, which is significantly different from the temperature of the battery cell 21 outside the battery pack 100, affecting the performance and life of the battery pack 100. Based on this situation, the low-temperature fluid flowing out of the refrigeration component flows into the reversing valve 33 from the liquid inlet 331 of the reversing valve 33. The low-temperature liquid flows in the reversing valve 33 in the direction of the internal flow. Figure 6 shown.

[0083] Adjust the states of the valves of the reversing valve 33: close the first valve 335 and the third valve 337, and open the second valve 336 and the fourth valve 338. In this case, the reversing valve 33 is in the first state, and the cryogenic liquid flows into the first channel 302 through the liquid inlet 331, flows into the second liquid outlet 333 through the second connecting channel 305 and the second channel 303, and then flows to the first connecting port 361 of the liquid cooling plate 36 through the first pipeline 34, that is, the cryogenic liquid flows into the middle position of the liquid cooling plate 36.

[0084] At this time, the low-temperature liquid first conducts heat convection with the battery cell 21 located in the middle of the battery pack 100, takes away the heat generated and accumulated by the battery cell 21, and reduces the temperature of the battery cell 21 in the middle. Furthermore, the low-temperature fluid flows in from the middle of the liquid cooling plate 36, flows along the circulation channel 363 toward the two side edges of the liquid cooling plate 36, and the low-temperature liquid flows from the inside to the outside, and finally flows through the battery cell 21 at the edge where the external temperature is lower, and after heat exchange with the battery cell 21 at the edge, it is guided out of the liquid cooling plate 36 from the second connecting ports 362 on both sides of the liquid cooling plate 36. The guided liquid enters the first channel 302 through the second pipeline 35 and the third liquid outlet 334, and then flows to the guide pipeline 32 through the first connecting channel 304 and the first liquid outlet 332. With such a configuration, the temperature difference between the middle position and the edge position of the battery pack 100 during charging and discharging can be reduced in a high temperature environment.

[0085] In a low temperature environment, the battery cell 21 will also generate heat during the charging and discharging process. However, since the end plate 22 located at the end of the battery cell module 20 and having a fixing and limiting function contacts the crossbeam 13, heat transfer will occur, resulting in a lower temperature of the battery cell 21 at the edge, and a large temperature difference with the battery cell 21 in the middle, which affects the performance and life of the battery pack 100.

[0086] Based on this situation, the high-temperature fluid flowing out of the heating component flows into the reversing valve 33 from the liquid inlet 331 of the reversing valve 33. The high-temperature liquid flows in the reversing valve 33 in the following direction: Figure 8 shown.

[0087] Adjust the status of each valve of the reversing valve 33: close the second valve 336 and the fourth valve 338, open the first valve 335 and the third valve 337. In this case, the reversing valve 33 is in the second state, and the high-temperature liquid flows into the first channel 302 and the second liquid outlet 333 through the liquid inlet 331, and then flows to the second connecting port 362 through the second pipeline 35, that is, the high-temperature liquid flows into the edge positions on both sides of the liquid cooling plate 36.

[0088] At this time, the high-temperature liquid first conducts heat exchange with the battery cells 21 at the edge to heat the battery cells 21 at the edge with lower temperature. Furthermore, the high-temperature fluid flows in from the edges of the liquid cooling plate 36 on both sides and flows along the circulation channel 363 toward the middle of the liquid cooling plate 36. The high-temperature liquid flows from the outside to the inside, and finally heats the battery cells 21 at the middle.

[0089] The high-temperature liquid after heat exchange is led out of the liquid cooling plate 36 from the first connecting port 361, and the led liquid enters the second channel 303 through the first pipeline 34 and the second liquid outlet 333, and flows to the first liquid outlet 332 and the lead-out pipeline 32 through the second channel 303. In this way, in a low-temperature environment, the temperature difference between the middle position and the edge position of the battery pack 100 during charging and discharging can be reduced.

[0090] like Fig. 9 Shown and see Figure 3 In the embodiment of the present application, the box body 11 is further provided with a crossbeam 13, and the crossbeam 13 is connected to the end plate 22 of each battery module 20 to fix each battery module 20. Along the second direction, the end plate 22 is provided at both ends of the battery module 20.

[0091] In order to reduce the heat transfer between the battery cells 21 at the edge and the end plate 22, a heat insulation plate 23 is provided between the end plate 22 and the battery cells 21. The heat insulation plate 23 can play the role of heat preservation, heat transfer prevention and insulation. It should be noted that the above-mentioned heat insulation plate 23 is also provided between each battery cell 21 of the battery cell module 20. Such a configuration improves the thermal management effect of the liquid cooling assembly 30 on the battery pack 100.

[0092] In the embodiment of the present application, a thermally conductive adhesive layer 40 is arranged between the battery cell module 20 and the liquid cooling plate 36. The thermally conductive adhesive layer 40 can not only support the battery cell module 20, but also make the heat between the liquid cooling plate 36 and the battery cell module 20 evenly distributed, thereby improving the thermal management effect of the liquid cooling component 30 on the battery pack 100.

[0093] In the embodiment of the present application, the battery pack 100 includes a plurality of battery modules 20, which are arranged in an array on the thermally conductive adhesive layer 40. Each battery module 20 includes a plurality of battery cells 21. In the same battery module 20, the plurality of battery cells 21 are arranged into two rows of battery cell 21 groups, and an isolation plate 24 is provided between two adjacent battery cell 21 groups. The isolation plate 24 may be an epoxy plate, which can play a role in insulation and preventing thermal runaway.

[0094] The various embodiments or implementation methods in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments, and the same or similar parts between the various embodiments can be referenced to each other.

[0095] It should be noted that the phrases "one embodiment", "an embodiment", "an exemplary embodiment", "some embodiments", etc. mentioned in the specification indicate that the described embodiments may include certain features, structures or characteristics, but not every embodiment may include the certain features, structures or characteristics. In addition, such phrases do not necessarily refer to the same embodiment. In addition, when describing certain features, structures or characteristics in conjunction with an embodiment, it is within the knowledge of those skilled in the art to implement such features, structures or characteristics in conjunction with other embodiments, whether explicitly or not explicitly described.

[0096] In general, terms should be understood, at least in part, by the context in which they are used. For example, the term "one or more" as used herein may be used to describe any feature, structure, or characteristic in a singular sense, or may be used to describe a combination of features, structures, or characteristics in a plural sense, depending, at least in part, on the context. Similarly, terms such as "a," "an," or "the" may also be understood to convey singular usage or to convey plural usage, depending, at least in part, on the context.

[0097] It should be easily understood that “on,” “above,” and “over” in the present disclosure should be interpreted in the broadest manner, so that “on” not only means “directly on something,” but also includes the meaning of “on something” with intervening features or layers therebetween, and “above” or “over” not only includes the meaning of “above” or “over,” but also may include the meaning of “above” or “over something” with no intervening features or layers therebetween (i.e., directly on something).

[0098] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A liquid cooling assembly for thermal management of a battery pack, characterized in that: The liquid cooling assembly includes a liquid cooling plate and a pipeline assembly; The liquid cooling plate comprises a heat exchange cavity and a first communication port and two second communication ports communicating with the heat exchange cavity; the heat exchange cavity is provided with a circulation channel, the first communication port is located in the middle of the circulation channel, and the two second communication ports are respectively provided at both ends of the circulation channel; The pipeline assembly includes a reversing valve and an injection pipeline and an outlet pipeline connected to the reversing valve. When the reversing valve is configured to be in a first state, the injection pipeline is connected to the first communication port, and the outlet pipeline is connected to the second communication port. Furthermore, when the reversing valve is in the second state, the injection pipeline is communicated with the second communication port, and the outlet pipeline is communicated with the first communication port.

2. The liquid cooling assembly according to claim 1, characterized in that: The liquid cooling plate includes a plurality of baffles; A plurality of the baffles are arranged in the heat exchange chamber at intervals along the first direction, two adjacent baffles form a flow channel, and the plurality of flow channels are connected end to end to form the circulation flow channel; Along the first direction, the two flow channels located at the middle position have a communication area, and the first communication port is communicated with the communication area.

3. The liquid cooling assembly according to claim 2, characterized in that: The reversing valve comprises a valve assembly and a liquid inlet, a first liquid outlet, a second liquid outlet and a third liquid outlet which are interconnected; The liquid inlet is connected to the injection pipeline, and the first liquid outlet is connected to the outlet pipeline; The second liquid outlet is communicated with the first communication port, and the third liquid outlet is communicated with two of the second communication ports respectively; The valve assembly is configured to control the liquid inlet to selectively communicate with the second liquid outlet or the third liquid outlet.

4. The liquid cooling assembly according to claim 3, characterized in that: The reversing valve comprises a valve body and a first channel, a second channel, a first communicating channel and a second communicating channel arranged in the valve body; The liquid inlet and the third liquid outlet are respectively located at two ends of the first channel, and the first liquid outlet and the second liquid outlet are respectively located at two ends of the second channel; The valve assembly includes a first valve, a second valve, a third valve and a fourth valve; the first valve is arranged in the first channel, the second valve is arranged in the first connecting channel, the third valve is arranged in the second channel, and the fourth valve is arranged in the second connecting channel.

5. The liquid cooling assembly according to claim 3, characterized in that: The pipeline assembly also includes a first pipeline and a second pipeline; The first pipeline is used to connect the second liquid outlet with the first communication port, and the second pipeline is used to connect the third liquid outlet with the two second communication ports.

6. The liquid cooling assembly according to claim 5, characterized in that: The second pipeline includes two connected branches; One end of the two branches is respectively communicated with the second communication port, and the other end of the two branches is respectively communicated with the third liquid outlet.

7. A battery pack, characterized in that: Comprising a battery box, at least one battery cell module and a liquid cooling assembly as described in any one of claims 1 to 6; The liquid cooling assembly is arranged at the bottom of the battery box, and the battery cell module is arranged in the battery box and is located on the liquid cooling plate of the liquid cooling assembly.

8. The battery pack according to claim 7, characterized in that: The liquid cooling assembly includes a reversing valve and an injection pipeline and an outlet pipeline connected to the reversing valve; The injection pipeline, the outlet pipeline and the reversing valve are located outside the battery box.

9. The battery pack according to claim 7, characterized in that: A thermally conductive adhesive layer is provided between the battery core module and the liquid cooling plate; The battery cell module includes a plurality of battery cells, and the plurality of battery cells are arranged into two rows of battery cell groups, and an isolation plate is provided between two adjacent battery cell groups.

10. The battery pack according to claim 9, characterized in that: End plates are respectively arranged at both ends of the battery core module, and a heat insulation plate is arranged between the end plates and the battery core.

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