Temperature control structure and battery pack

Abstract

A temperature control structure and a battery pack. The temperature control structure comprises a serpentine assembly, two liquid flowing assemblies, and a lower cold plate; the serpentine assembly comprises a plurality of serpentine members; the two liquid flowing assemblies are respectively located at two ends of the serpentine assembly; the lower cold plate is located below the serpentine assembly; every two adjacent serpentine members and the lower cold plate form an accommodating space; the accommodating space is used for accommodating a plurality of battery cells; a plurality of first flow channels are formed inside the lower cold plate; two ends of each first flow channel are respectively communicated with the two liquid flowing assemblies; two ends of each serpentine member are respectively communicated with the two liquid flowing assemblies; a temperature control liquid can enter from one of the liquid flowing assemblies and flow out from the other liquid flowing assembly.

Description

Temperature control structure and battery pack

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on July 18, 2023, with application number 202321889365.5. The entire contents of the above application are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of battery technology, and in particular to a temperature control structure and a battery pack. Background Art

[0003] With the rapid development of new energy vehicles, pure electric vehicle users have higher and higher requirements for vehicle range and charging rate, which has led to higher and higher energy of battery cells. This has led to higher and higher heat generation during operation of battery cells. At the same time, as the number of battery cells and charging rate increase, temperature consistency becomes more difficult to control, and more efficient temperature control solutions are needed to cool and equalize the temperature of the battery cells.

[0004] In the related art, cylindrical battery packs suffer from the problem of excessive heat generation. Most commercially available solutions use a single-sided thermostat with a serpentine element. The serpentine element contacts the side end face of the battery cell, and the thermostat liquid flows within the serpentine element cavity, creating convection heat exchange with the battery cell. Under high-rate charging conditions, it is difficult to maintain an ideal temperature, posing a significant risk to battery cell life and driving safety. Furthermore, the serpentine elements in the related art use a series connection for injecting thermostat liquid, resulting in a high flow resistance for the thermostat liquid within them. Furthermore, due to the series connection, the temperature of the thermostat liquid is already elevated by the time it reaches the cell being thermostated, resulting in a poor thermostating effect and a poor temperature balance across multiple cells. SUMMARY OF THE INVENTION

[0005] The present application provides a temperature control structure and a battery pack to solve the above technical problems.

[0006] In the first aspect, the present application provides a temperature control structure for regulating the temperature of a battery pack, the temperature control structure including a serpentine component, two fluid components and a lower cold plate; the serpentine component includes a plurality of serpentine parts, and the plurality of serpentine parts are arranged at intervals along a first direction; the two fluid components are respectively located at both ends of the serpentine component; the lower cold plate is located below the serpentine component, and the two adjacent serpentine parts and the lower cold plate form a accommodating space, the accommodating space is used to accommodate a plurality of battery cells, and a plurality of first flow channels are formed inside the lower cold plate, and the two ends of each first flow channel are respectively connected to the two fluid components, and the two ends of each serpentine part are respectively connected to the two fluid components, and the temperature control liquid can enter from one of the fluid components and flow out from the other fluid component.

[0007] In a second aspect, the present application also provides a battery pack comprising a plurality of battery cells and the above-mentioned temperature control structure, wherein a plurality of battery cells are arranged in each accommodating space. Beneficial effects

[0008] The beneficial effects of the present application are as follows: the temperature control structure provided by the present application, on the one hand, cools the battery cell by adding a lower cold plate and a serpentine component, thereby increasing the contact area between the battery cell and the temperature control structure so that both sides and the bottom of each battery cell are cooled, thereby improving the temperature control effect of the battery cell; on the other hand, through the arrangement of the liquid flow component, one of the liquid flow components serves as the liquid inlet end. After the temperature control liquid enters from this end, multiple serpentine components flow into the temperature control liquid at the same time, and multiple first flow channels flow into the temperature control liquid at the same time. After heat exchange, the temperature control liquid is collected and flows out of the liquid flow component at the other end as the liquid outlet end, so that the temperature control liquid is divided into several parts to cool the battery cells separately. From the liquid inlet end to the liquid outlet end, compared with the series connection, the travel path of each part of the temperature control liquid is shortened, and the temperature control effect of the battery cell that is temperature controlled later is not much different from that of the battery cell that is temperature controlled earlier, thereby improving the temperature consistency of multiple battery cells; and after parallel connection, the travel path of each temperature control liquid is shortened, the flow resistance is reduced, which is conducive to the renewal of the temperature control liquid and further improves the cooling speed.

[0009] The battery pack provided in the present application, by adopting the above-mentioned temperature control structure, can improve the temperature control effect of the battery cells and ensure the temperature consistency of multiple battery cells. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] FIG1 is a schematic structural diagram of a battery pack provided in this application;

[0011] FIG2 is an exploded schematic diagram of the temperature control structure provided by the present application;

[0012] FIG3 is a schematic structural diagram of a parallel component provided in this application;

[0013] FIG4 is an enlarged schematic diagram of point A in FIG2 .

[0014] Description of reference numerals:

[0015] 10. Serpentine assembly; 11. Serpentine part; 111. Second flow channel; 20. Liquid flow assembly; 21. Liquid injection pipe; 22. Parallel part; 221. Liquid flow hole; 222. First liquid injection port; 223. Third liquid injection port; 23. Liquid inlet; 24. Liquid outlet; 30. Lower cold plate; 31. Upper plate; 311. Second liquid injection port; 32. Lower plate; 321. First flow channel; 33. Pressure relief channel; 40. Accommodation space; 200. Battery cell. Modes for Carrying Out the Invention

[0016] In the description of this application, unless otherwise specified or limited, the terms "connected," "connect," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and can refer to internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0017] In this application, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0018] In the description of this embodiment, the terms "upper," "lower," "right," and other orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely for ease of description and simplified operation. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first" and "second" are used solely for descriptive purposes and have no special meanings.

[0019] This embodiment provides a temperature control structure that adds a lower cold plate 30 to simultaneously control the temperature of the battery cell 200, thereby improving the temperature control effect of the battery cell 200. Furthermore, multiple serpentine elements 11 and multiple first flow channels 321 are all injected with temperature control liquid through the fluid assembly 20, and are connected in parallel to reduce the flow resistance of the temperature control system, thereby ensuring temperature consistency of the battery cell 200. As shown in FIG1 , the temperature control structure includes a serpentine assembly 10, which includes multiple serpentine elements 11. The multiple serpentine elements 11 are arranged in a first direction (the first direction is the X direction shown in FIG1 ) at intervals. The battery cell 200 can be accommodated between two adjacent serpentine elements 11, so that the opposite sides of the battery cell 200 are cooled. However, the cooling effect of the above-mentioned cooling method is difficult to meet high-rate power supply conditions. In the related art, multiple serpentine elements 11 are injected with temperature control liquid in series, which has a large flow resistance and poor temperature consistency of the multiple battery cells 200.

[0020] In order to solve the above problems, as shown in Figures 1 and 2, the temperature control structure provided in this embodiment also includes two fluid components 20 and a lower cold plate 30. The two fluid components 20 are respectively located at the two ends of the serpentine component 10, and the lower cold plate 30 is located below the serpentine component 10 and the two fluid components 20. The two adjacent serpentine parts 11 and the lower cold plate 30 form a accommodating space 40. The accommodating space 40 is used to accommodate multiple battery cells 200. A plurality of first flow channels 321 are formed inside the lower cold plate 30. The two ends of each first flow channel 321 are respectively connected to the two fluid components 20, and the two ends of each serpentine part 11 are respectively connected to the two fluid components 20. The temperature control liquid can enter from one of the fluid components 20 and flow out from the other fluid component 20.

[0021] The above-mentioned temperature control structure, on the one hand, cools down the battery cell 200 by adding the lower cold plate 30 and the serpentine component 10, thereby increasing the contact area between the battery cell 200 and the temperature control structure so that both sides and the bottom of each battery cell 200 are cooled, thereby improving the temperature control effect of the battery cell 200; on the other hand, through the setting of the liquid flow component 20, one of the liquid flow components 20 is used as the liquid inlet end 23, after the temperature control liquid enters from this end, multiple serpentine parts 11 flow into the temperature control liquid at the same time, and multiple first flow channels 321 flow into the temperature control liquid at the same time, and the temperature control liquid is cooled after heat exchange. The liquid flow components 20 gathered at the other end as the liquid outlet 24 flow away, so that the temperature-regulating liquid is divided into several parts to cool the battery cells 200 separately. From the liquid inlet 23 to the liquid outlet 24, compared with the series connection, the travel path of each part of the temperature-regulating liquid becomes shorter, and the temperature-regulating effect of the battery cell 200 that is temperature-regulated later is not much different from the temperature-regulating effect of the battery cell 200 that is temperature-regulated earlier, thereby improving the temperature consistency of multiple battery cells 200; and after parallel connection, the travel path of each temperature-regulating liquid becomes shorter and the flow resistance becomes smaller, which is conducive to the renewal of the temperature-regulating liquid and further improves the cooling speed.

[0022] It should be noted that the temperature-adjusting liquid may be a cooling liquid or a heating liquid, and may be appropriately adjusted according to the operating temperature of the battery cell 200 , and is not limited here.

[0023] Optionally, as shown in FIG1 , the fluid assembly 20 includes a plurality of sequentially connected injection tubes 21, with adjacent injection tubes 21 connected via a parallel member 22. Each serpentine member 11 has two ends connected to the parallel member 22, and each first flow channel 321 has two ends connected to the parallel member 22. This arrangement allows the fluid assembly 20 to have a more regular structure and occupy less space.

[0024] In other embodiments, the connecting member 22 may be replaced by a pipeline with branches, which is not limited here.

[0025] As shown in FIG1 , the liquid inlet end 23 and the liquid outlet end 24 are respectively the liquid injection pipes 21 at the ends of the two liquid flow components 20 , and the liquid inlet end 23 and the liquid outlet end 24 can be used interchangeably.

[0026] In this embodiment, as shown in FIG2 , the number of first flow channels 321 is set to be the same as the number of serpentine members 11, and the first flow channels 321 are located below the serpentine member 11. That is, each parallel member 22 in this embodiment has the function of communicating with the serpentine member 11 and with the first flow channel 321. In other embodiments, the second flow channel 111 can be added on the basis of this embodiment. For example, the second flow channel 111 is provided below the battery cell 200, and corresponding parallel members 22 are provided at both ends of the second flow channel 111. The parallel members 22 only need to ensure communication with the second flow channel 111. The above method can increase the flow rate of the temperature-control liquid in the lower cold plate 30 and further improve the temperature-control speed of the battery cell 200.

[0027] Specifically, as shown in Figures 2 and 3, the interior of the parallel member 22 is hollow, and liquid flow holes 221 are provided on both sides in the first direction. Each of the two liquid flow holes 221 is connected to a liquid injection pipe 21. A first liquid injection port 222 is provided below the parallel member 22, and a second liquid injection port 311 is provided at both ends of the first flow channel 321. A parallel member 22 is provided above each second liquid injection port 311 to connect the second liquid injection port 311 with the corresponding first liquid injection port 222. Through the above arrangement, the parallel member 22 is connected to the first flow channel 321.

[0028] Optionally, the parallel piece 22 and the lower cold plate 30 are connected by welding, which can ensure good sealing between the two.

[0029] Specifically, the lower cold plate 30 includes an upper plate 31 and a lower plate 32 connected to each other. The upper plate 31 is flat, and a plurality of downward grooves are opened on the lower plate 32 to form a first flow channel 321. The second liquid injection port 311 is opened on the upper plate 31 and is located at both ends of the first flow channel 321.

[0030] Preferably, the upper plate 31 and the lower plate 32 are provided with a plurality of through holes to form a pressure relief channel 33. Each pressure relief channel 33 is provided corresponding to a battery cell 200, so that the high-temperature expansion gas can be dissipated therefrom to ensure the safety of the battery pack in a thermal runaway state.

[0031] It should be noted that, in other embodiments, when the first flow channel 321 is disposed at the bottom of the battery cell 200 , the first flow channel 321 and the pressure relief channel 33 may be disposed in a manner avoiding each other.

[0032] Furthermore, as shown in FIG2 , the parallel member 22 connected to the serpentine 11 is further provided with a third liquid injection port 223, which is connected to the end of the serpentine 11. This arrangement ensures that the parallel member 22 is connected to the serpentine 11. In other words, the parallel member 22 connected to the first flow channel 321 only needs to have the liquid flow hole 221 and the first liquid injection port 222. However, the parallel member 22 that needs to simultaneously connect to the first flow channel 321 and the serpentine tube, as shown in FIG3 , also needs to have the third liquid injection port 223.

[0033] Preferably, the end of the serpentine member 11 is inserted into the third liquid injection port 223 and then welded to the parallel member 22. Through the above arrangement, the plug-in method can ensure fast installation and stable connection, and the sealing of the two is better after welding.

[0034] Preferably, as shown in FIG4 , a plurality of second flow channels 111 are formed in the serpentine 11 in an upper and lower arrangement, each of which is connected to the third liquid injection port 223. This arrangement allows the temperature-control liquid to be evenly distributed in the serpentine 11, preventing the temperature-control liquid from falling under the serpentine 11 due to gravity when the volume is small, thereby preventing the upper portion of the battery cell 200 from being temperature-controlled. This ensures temperature uniformity in the Z direction for each battery cell 200.

[0035] Specifically, the first flow channel 321 extends along the second direction (the Y direction in the figure, where the Y direction is perpendicular to the X direction and the Z direction respectively) to facilitate processing.

[0036] Preferably, in other embodiments, the first flow channel 321 is arranged in a non-linear manner to form a turbulent structure, so that the temperature-regulating liquid fully contacts the upper plate 31 when flowing in the first flow channel 321, thereby allowing the temperature-regulating liquid to have sufficient time to cool the battery cell 200, thereby improving the adequacy of the low-temperature utilization of the temperature-regulating liquid.

[0037] This embodiment further provides a battery pack, which can improve the temperature regulation effect of the battery cells 200 and ensure the temperature consistency of multiple battery cells 200.

[0038] Specifically, referring to Figure 1 , the battery pack includes multiple battery cells 200 and the aforementioned temperature control structure, with multiple battery cells 200 arranged in each accommodating space 40. By employing the aforementioned temperature control structure, the battery pack can improve the temperature control effect of the battery cells 200 and ensure temperature consistency among the multiple battery cells 200.

[0039] The battery pack preferably also includes side frames (not shown), which together with the lower cold plate 30 form the battery pack housing. This arrangement allows the lower cold plate 30 to function as both a structural member (equivalent to the conventional bottom frame) and a temperature regulator, enabling both high-rate fast charging and a lightweight battery pack design, thereby increasing the pack's energy density.

[0040] Preferably, the box side frame is connected to the lower cold plate 30 by friction stir welding. Friction stir welding has the advantages of high efficiency, low cost, and high bonding strength, while ensuring that the structural strength of the lower cold plate 30 and the box side frame is not damaged.

[0041] Preferably, thermally conductive structural adhesive is provided between the battery cell 200 and the lower cold plate 30 , and between the battery cell 200 and the serpentine member 11 , to ensure the structural strength of the temperature regulating structure and the entire battery.

Claims

1. A temperature regulating structure for regulating the temperature of a battery pack, the temperature regulating structure comprising: A serpentine assembly (10) comprising a plurality of serpentine members (11), wherein the plurality of serpentine members (11) are arranged at intervals along a first direction; Two fluid flow components (20), respectively located at two ends of the serpentine component (10); as well as, The lower cold plate (30) is located below the serpentine component (10) and the two fluid components (20). The two adjacent serpentine components (11) and the lower cold plate (30) form a containing space (40). The containing space (40) is used to contain a plurality of battery cells (200). A plurality of first flow channels (321) are formed inside the lower cold plate (30). The two ends of each of the first flow channels (321) are respectively connected to the two fluid components (20). The two ends of each of the serpentine components (11) are respectively connected to the two fluid components (20). The temperature regulating liquid enters from one of the fluid components (20) and flows out from the other fluid component (20).

2. The temperature adjustment structure according to claim 1, wherein: The liquid flow component (20) comprises a plurality of injection pipes (21) connected in sequence, and two adjacent injection pipes (21) are connected via a parallel piece (22); both ends of each serpentine piece (11) are connected to the parallel piece (22), and both ends of each first flow channel (321) are connected to the parallel piece (22).

3. The temperature adjustment structure according to claim 2, wherein: The parallel component (22) is hollow inside and has liquid flow holes (221) on both sides in the first direction. A liquid injection pipe (21) is connected to each of the two liquid flow holes (221). A first liquid injection port (222) is provided below the parallel component (22). Second liquid injection ports (311) are provided at both ends of the first flow channel (321). A parallel component (22) is provided above each of the second liquid injection ports (311) so that the second liquid injection port (311) is connected to the corresponding first liquid injection port (222).

4. The temperature regulating structure according to claim 3, wherein: The parallel member (22) connected to the serpentine member (11) is also provided with a third liquid injection port (223), and the third liquid injection port (223) is connected to the end of the serpentine member (11).

5. The temperature adjustment structure according to claim 4, wherein: A plurality of second flow channels (111) arranged vertically are formed in the serpentine member (11), and each of the second flow channels (111) is connected to the third liquid injection port (223).

6. The temperature regulating structure according to claim 3, wherein: The serpentine member (11) is connected to the parallel member (22) by welding.

7. The temperature regulating structure according to any one of claims 2 to 5, wherein: The parallel component (22) and the lower cold plate (30) are connected by welding.

8. The temperature regulating structure according to any one of claims 1 to 5, wherein: The first flow channel (321) is arranged in a non-linear manner.

9. The temperature regulating structure according to claim 1, wherein: The lower cold plate (30) comprises an upper plate (31) and a lower plate (32) which are connected, the upper plate (31) being in the shape of a flat plate, and a plurality of grooves are formed on the lower plate (32), wherein the grooves form the first flow channel (321).

10. The temperature adjustment structure according to claim 8, wherein: The upper plate (31) is formed with a plurality of first through holes arranged at intervals, and the lower plate (32) is formed with a plurality of second through holes corresponding to the first through holes, wherein the first through holes and the second through holes constitute a pressure relief channel.

11. The temperature regulating structure according to claim 9, wherein: The first flow channel (321) and the pressure relief channel (33) are arranged in a staggered manner.

12. The temperature regulating structure according to claim 1, wherein: The number of the first flow channels (321) is set to be the same as the number of the serpentine members (11).

13. The temperature regulating structure according to claim 12, wherein: The number of the first flow channels is six; and / or, The number of the serpentine members is six.

14. A battery pack comprising: A plurality of battery cells (200); as well as, According to the temperature control structure according to any one of claims 1 to 7, a plurality of battery cells (200) are arranged in each of the accommodating spaces (40).

15. The battery pack according to claim 14, wherein: The battery pack also includes a box body side frame, the box body side frame and the lower cold plate (30) form a box body of the battery pack, and the box body side frame and the lower cold plate (30) are connected around by stir friction welding.

16. The battery pack according to claim 14, wherein: Thermally conductive structural adhesive is provided between the battery core (200) and the lower cold plate (30), and between the battery core (200) and the serpentine member (11).

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