Liquid cooling plate and battery temperature control structure

Abstract

The utility model discloses a liquid cooling board and battery temperature control structure relates to battery temperature control technical field. Liquid cooling board includes apron and base plate, wherein, base plate is set with liquid inlet channel, liquid outlet channel and diffusion channel, and the both ends of diffusion channel are communicated with liquid inlet channel and liquid outlet channel respectively, and apron fixed cover is set in base plate, diffusion channel includes two groups binary fractal channel and a plurality of straight line channels, definition: the projection of base plate projection on apron is first projection, the shape of first projection is rectangle, and two groups binary fractal channel are set along the central axis of first projection length direction symmetry, and binary fractal channel includes a root end and a plurality of terminal, wherein a root end is communicated with liquid inlet channel, and another root end is communicated with liquid outlet channel, and the both ends of straight line channel are communicated with two symmetrically arranged terminals in two groups binary fractal channel respectively. Like this, the refrigeration effect of cooling plate is more uniform, can satisfy the heat dissipation requirement of high energy density battery.

Description

Technical Field

[0001] This utility model relates to the field of battery temperature control technology, and in particular to a liquid cooling plate and a battery temperature control structure. Background Technology

[0002] In the thermal management system of vehicle batteries, battery modules primarily dissipate heat through liquid cooling plates. Coolant flows through the liquid cooling plates, carrying away the heat transferred from the battery modules. Currently, common liquid cooling plates typically employ parallel or serpentine flow channels, which offer advantages such as simple structure and low flow resistance. However, with the development of new energy technologies, battery modules are continuously increasing in size and energy density per unit volume, thus placing higher demands on the heat dissipation performance of liquid cooling plates. Common liquid cooling plates struggle to ensure uniform coolant distribution within the flow channels, resulting in uneven heat dissipation from the battery modules and consequently compromising their heat dissipation efficiency.

[0003] In view of this, the present invention proposes a liquid cooling plate and a battery temperature control structure to solve or at least alleviate the above problems. Utility Model Content

[0004] The main purpose of this utility model is to propose a liquid cooling plate and battery temperature control structure, which aims to solve the technical problem that high energy density battery modules require uniform and efficient heat dissipation conditions, while traditional liquid cooling plates cannot meet this requirement.

[0005] To achieve the above objectives, this utility model proposes a liquid cooling plate, comprising:

[0006] Cover plate;

[0007] A substrate having an inlet channel, an outlet channel, and a diffusion channel, wherein the two ends of the diffusion channel are respectively connected to the inlet channel and the outlet channel, and a cover plate is fixedly installed on the substrate.

[0008] The diffusion channel includes two sets of bifurcated fractal channels and multiple straight channels;

[0009] Definition: The projection of the substrate onto the cover plate is the first projection;

[0010] The first projection is rectangular in shape. The two sets of bifurcated flow channels are symmetrically arranged along the central axis of the length direction of the first projection. Each bifurcated flow channel includes a root end and multiple ends. One root end is connected to the inlet flow channel, and the other root end is connected to the outlet flow channel. The two ends of the straight flow channel are respectively connected to two symmetrically arranged ends in the two sets of bifurcated flow channels.

[0011] In one embodiment, the number of diffusion channels is at least two, and the at least two diffusion channels are arranged in parallel along the length direction of the first projection.

[0012] In one embodiment, the bifurcation fractal flow channel includes a root flow channel, a primary flow channel, a secondary flow channel, and a tertiary flow channel. The root flow channel is connected to two primary flow channels, each primary flow channel is connected to two secondary flow channels, and each secondary flow channel is connected to two tertiary flow channels. The root flow channel, the primary flow channel, the secondary flow channel, and the tertiary flow channel form a bifurcation fractal structure.

[0013] The root end is located at the end of the root channel away from the first-level channel, and the end end is located at the end of the third-level channel away from the second-level channel.

[0014] In one embodiment, the widths of the root channel, the primary channel, the secondary channel, and the tertiary channel are defined as D1, D2, D3, and D4, respectively.

[0015] Then, D4 / D3=[0.6, 1], D3 / D2=[0.6, 1], D2 / D1=[0.6, 1].

[0016] In one embodiment, the lengths of the root channel, the primary channel, the secondary channel, and the tertiary channel are defined as L1, L2, L3, and L4, respectively.

[0017] Then, L4 / L3=[0.6, 1], L3 / L2=[0.6, 1], L2 / L1=[0.6, 1].

[0018] In one embodiment, the angle between the primary flow channel and the root flow channel is defined as α1, the angle between the secondary flow channel and the primary flow channel is defined as α2, and the angle between the tertiary flow channel and the secondary flow channel is defined as α3.

[0019] Then, α1, α2, α3 ∈ (90°, 180°).

[0020] In one embodiment, the liquid inlet channel includes an inlet section and a diffusion section that are interconnected, and the diffusion section is connected to the root end of the diffusion channel;

[0021] The liquid inlet section includes at least two liquid inlets, which are used to communicate with an external liquid pump;

[0022] The liquid outlet channel includes a liquid outlet, and the liquid inlet and the liquid outlet are respectively opened on both sides of the substrate along the length direction of the first projection.

[0023] In one embodiment, the substrate is made of aluminum alloy.

[0024] This utility model also proposes a battery temperature control structure, including a liquid cooling plate as described in any of the above embodiments, and the battery temperature control structure further includes a battery plate and a phase change interlayer.

[0025] The two sides of the phase change interlayer are respectively bonded to the solar panel and the substrate;

[0026] Alternatively, the two sides of the phase change interlayer are respectively attached to the battery panel and the cover plate.

[0027] In one embodiment, the battery temperature control structure further includes a controller and a temperature sensor and a liquid pump communicatively connected to the controller. The temperature sensor is used to monitor the temperature information of the surface of the battery panel, the controller is used to receive the temperature information, and the liquid pump is connected to the liquid inlet channel.

[0028] According to the technical solution of this utility model, the liquid cooling plate includes a cover plate and a substrate. The substrate has an inlet channel, an outlet channel, and a diffusion channel. The two ends of the diffusion channel are respectively connected to the inlet channel and the outlet channel. The cover plate is fixedly placed on the substrate. The diffusion channel includes two sets of bifurcated fractal channels and multiple straight channels. Definition: The projection of the substrate onto the cover plate is the first projection. The shape of the first projection is rectangular. The two sets of bifurcated fractal channels are symmetrically arranged along the central axis of the length direction of the first projection. The bifurcated fractal channel includes one root end and multiple ends. One end is connected to the inlet channel, and the other end is connected to the outlet channel. The two ends of the straight channels are respectively connected to two symmetrically arranged ends of the two sets of bifurcated fractal channels. Because the diffusion channel adopts a bifurcation fractal structure, the coolant can diffuse in multiple directions after entering the first set of bifurcation fractal channels and enter the second set of bifurcation fractal channels through the end. Furthermore, the two sets of bifurcation fractal channels are symmetrically arranged, which can improve the uniformity of coolant distribution in the substrate. Thus, under the same coolant flow rate, compared with commonly used liquid cooling plates, the coolant distribution in the substrate is more uniform, thereby making the cooling effect of the liquid cooling plate more uniform. When applied to the heat dissipation of battery modules, it can achieve a more uniform and efficient heat dissipation effect. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0030] Figure 1 A schematic diagram of the structure of an embodiment of the liquid cooling plate provided by this utility model;

[0031] Figure 2 A schematic diagram of the planar structure of an embodiment of the substrate provided by this utility model;

[0032] Figure 3 for Figure 2 A schematic diagram showing the flow direction of coolant in the provided substrate;

[0033] Figure 4 for Figure 2 A schematic diagram of the diffusion channel structure in the provided substrate;

[0034] Figure 5 for Figure 4 A schematic diagram of the bifurcation fractal flow channel in the provided diffusion channel;

[0035] Figure 6 This is a schematic diagram of an embodiment of the battery temperature control structure provided by this utility model.

[0036] Explanation of icon numbers:

[0037] 1000, Liquid cooling plate;

[0038] 1. Cover plate;

[0039] 2. Substrate; 21. Liquid inlet channel; 211. Liquid inlet section; 212. Diffusion section; 213. Liquid inlet; 22. Liquid outlet channel; 221. Liquid outlet; 23. Diffusion channel; 231. Diagonal fractal channel; 2311. Root end; 2312. End end; 2313. Root channel; 2314. Primary channel; 2315. Secondary channel; 2316. Tertiary channel; 232. Straight channel;

[0040] 2000, solar panel; 3000, phase change interlayer.

[0041] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0042] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0043] It should be noted that if the embodiments of this utility model involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0044] Furthermore, if the embodiments of this utility model involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0045] In the core architecture of the thermal management system for new energy vehicles, the heat dissipation efficiency of the battery module directly affects the overall vehicle performance and safety. Current mainstream liquid cooling solutions use liquid cooling plates as the heat transfer medium. Their working principle involves the circulating coolant absorbing the heat generated by the battery module, and then releasing the heat to the external environment via a heat exchanger. The internal flow channel design of the liquid cooling plate is a key factor affecting heat dissipation. Currently, the industry commonly uses two structural forms: parallel flow channels and serpentine flow channels. Parallel flow channels achieve coolant distribution through a multi-channel parallel layout, featuring low flow resistance and low pressure drop. Serpentine flow channels, on the other hand, extend the coolant flow path through a winding, single channel, increasing the heat exchange area within a limited space. Both flow channel designs have the advantages of simple structure and low manufacturing cost, and have been proven through long-term engineering to meet the heat dissipation needs of small and medium-sized battery modules, thus being widely used in existing vehicle models.

[0046] With the iterative upgrades of new energy technologies, battery module design is showing a dual trend of increasing volume and improving energy density. Taking a certain brand's ternary lithium battery as an example, its volumetric energy density has exceeded 300Wh / kg, an improvement of about 15% compared to the previous generation. At the same time, the increased module volume leads to a wider distribution range of heat sources. This change places higher demands on the heat dissipation uniformity of the liquid cooling plate. Traditional parallel flow channels have an inherent defect of uneven flow distribution, with the flow rate of the sub-channels near the inlet being significantly higher than that of the end channel, causing local overcooling or overheating. Although serpentine flow channels can ensure consistent flow within the channel, the centrifugal force at the bends causes a velocity gradient in the turning area of ​​the coolant, resulting in a flow characteristic of faster flow on the outside and slower flow on the inside. This non-uniform flow field distribution can cause temperature differences of more than 5°C in different areas of the battery module, far exceeding the industry standard of 2°C temperature control. Under long-term operation, the temperature gradient will trigger a chain reaction such as inconsistent battery internal resistance and asynchronous capacity decay, ultimately leading to a shortened overall module lifespan and seriously restricting the reliability and economy of new energy vehicles.

[0047] In view of the above, this utility model proposes a liquid cooling plate to solve the above problems.

[0048] Please see Figures 1 to 5 In one embodiment of this utility model, the liquid cooling plate 1000 includes a cover plate 1 and a substrate 2. The substrate 2 has an inlet channel 21, an outlet channel 22 and a diffusion channel 23. The two ends of the diffusion channel 23 are respectively connected to the inlet channel 21 and the outlet channel 22. The cover plate 1 is fixedly covered on the substrate 2. The diffusion channel 23 includes two sets of bifurcated fractal channels 231 and multiple straight channels 232. Definition: The projection of the substrate 2 onto the cover plate 1 is the first projection. The shape of the first projection is rectangular. The two sets of bifurcated fractal channels 231 are symmetrically arranged along the central axis of the length direction of the first projection. The bifurcated fractal channel 231 includes a root end 2311 and multiple ends 2312. One end 2311 is connected to the inlet channel 21 and the other end 2311 is connected to the outlet channel 22. The two ends of the straight channels 232 are respectively connected to two symmetrically arranged ends 2312 of the two sets of bifurcated fractal channels 231.

[0049] Specifically, the flow path of the coolant in the substrate 2 is as follows: inlet channel 21, root end 2311, bifurcation fractal channel 231, end 2312, straight channel 232, end 2312, bifurcation fractal channel 231, root end 2311, outlet channel 22. The bifurcation fractal channel 231 includes multiple branches, the specific number of which can be flexibly adjusted according to the size of the substrate 2 and design requirements, such as a three-level or four-level fractal structure. The length of the straight channel 232 is adapted to the length between the symmetrical ends 2312 of the two sets of bifurcation fractal channels 231, and all straight channels 232 are arranged in parallel to reduce the design and manufacturing difficulty of the straight channels 232. In this embodiment, the inlet channel 21, the outlet channel 22 and the diffusion channel 23 are all formed by photochemical etching process, and the inner wall surface of each channel is anodized. The cover plate 1 is made of thermally conductive silicone and encapsulated on the substrate 2 by laser welding process.

[0050] According to the technical solution provided in this embodiment, since the diffusion channel 23 adopts a bifurcation fractal structure, the coolant can diffuse in multiple directions after entering the first set of bifurcation fractal channels 231, and enter the second set of bifurcation fractal channels 231 through the end 2312. Furthermore, the two sets of bifurcation fractal channels 231 are symmetrically arranged, which can improve the uniformity of coolant distribution in the substrate 2. Thus, under the same coolant flow rate, compared with the commonly used liquid cooling plate 1000, the coolant distribution in the substrate 2 is more uniform, thereby making the cooling effect of the liquid cooling plate 1000 more uniform. When applied to the heat dissipation of battery modules, it can achieve a more uniform and efficient heat dissipation effect.

[0051] Compared to the biomimetic leaf vein-shaped flow channel in substrate 2, the bifurcation fractal flow channel 231 adopts a progressively symmetrical structure, which has the characteristic of progressively splitting the flow, thus enabling a more uniform distribution of coolant in substrate 2. While the biomimetic leaf vein-shaped flow channel typically has a main vein and multiple branch veins on both sides of the main vein, although it can also make the coolant distribution in the liquid cooling plate more uniform to some extent, this design results in a larger flow rate in the branch veins near the inlet flow channel 21 and a smaller flow rate in the branch veins near the outlet flow channel 22. Therefore, the biomimetic leaf vein-shaped flow channel still suffers from uneven flow, making it difficult to meet the heat dissipation requirements of high-energy-density batteries.

[0052] In one embodiment of this utility model, please refer to Figure 2The number of diffusion channels 23 is at least two, and the at least two diffusion channels 23 are arranged in parallel along the length direction of the first projection. In order to avoid too many stages in the bifurcation channel 231 and to make the diffusion channels 23 as much as possible on the substrate 2, in this embodiment, multiple diffusion channels 23 are set and arranged in parallel along the length direction of the substrate 2. In this way, it is possible to avoid the excessive specific surface area of ​​the channel due to too many stages, which would cause a significant pressure drop, and to reduce the processing difficulty of the diffusion channels 23 while ensuring the coverage area of ​​the diffusion channels 23, thereby improving the production efficiency of the substrate 2.

[0053] Please see Figure 2 , Figure 4 and Figure 5 In one embodiment of this utility model, the bifurcation fractal flow channel 231 includes a root flow channel 2313, a primary flow channel 2314, a secondary flow channel 2315, and a tertiary flow channel 2316. The root flow channel 2313 is connected to two primary flow channels 2314, each primary flow channel 2314 is connected to two secondary flow channels 2315, and each secondary flow channel 2315 is connected to two tertiary flow channels 2316. The root flow channel 2313, the primary flow channel 2314, the secondary flow channel 2315, and the tertiary flow channel 2316 form a bifurcation fractal structure. The root end 2311 is located at the end of the root flow channel 2313 away from the primary flow channel 2314, and the end end 2312 is located at the end of the tertiary flow channel 2316 away from the secondary flow channel 2315. In this embodiment, a set of bifurcation flow channels 231 includes one root flow channel 2313, two primary flow channels 2314, four secondary flow channels 2315, and eight tertiary flow channels 2316. Thus, the bifurcation flow channels 231 with three-stage fractals can ensure that the diffusion area of ​​the bifurcation flow channels 231 in the substrate 2 is large enough, and can also avoid the narrow width of the final flow channel due to too many stages, which would result in excessive pressure drop in the bifurcation flow channels 231.

[0054] Further, in one embodiment of this utility model, the widths of the root channel 2313, the primary channel 2314, the secondary channel 2315, and the tertiary channel 2316 are defined as D1, D2, D3, and D4, respectively; then, D4 / D3 = [0.6, 1], D3 / D2 = [0.6, 1], and D2 / D1 = [0.6, 1]. In this embodiment, D4 / D3 = 0.8, D3 / D2 = 0.8, and D2 / D1 = 0.8. This gradually reduces the width of each channel, resulting in a more reasonable flow resistance gradient and preventing pressure drop concentration at the end 2312, thus making the overall pressure drop distribution more uniform.

[0055] Furthermore, in one embodiment of this utility model, the lengths of the root channel 2313, the first-stage channel 2314, the second-stage channel 2315, and the third-stage channel 2316 are defined as L1, L2, L3, and L4, respectively; then, L4 / L3 = [0.6, 1], L3 / L2 = [0.6, 1], and L2 / L1 = [0.6, 1]. In this embodiment, L4 / L3 = 0.8, L3 / L2 = 0.8, and L2 / L1 = 0.8. This causes each stage of the channel to shorten progressively. This design allows each stage of the channel to compensate for the pressure rise by reducing the flow path length. Combined with the progressively shortened width of each stage of the channel, the overall pressure drop distribution in the bifurcation fractal channel 231 becomes more uniform, avoiding excessive pressure drop and reducing the energy consumption of the external liquid pump.

[0056] In one embodiment of this utility model, please refer to Figure 5 Define: the angle between the primary flow channel 2314 and the root flow channel 2313 is α1, the angle between the secondary flow channel 2315 and the primary flow channel 2314 is α2, and the angle between the tertiary flow channel 2316 and the secondary flow channel 2315 is α3; then, α1, α2, α3 ∈ (90°, 180°). In this embodiment, α1, α2, and α3 are all set to 150°. This angle can ensure the extended area of ​​the bifurcation flow channel 231 while avoiding excessive impact on the smoothness of coolant flow, and can also avoid uneven coolant flow velocity between the inner and outer layers in the bending areas of each flow channel due to excessively small angles.

[0057] In one embodiment of this utility model, please refer to Figure 2 The inlet channel 21 includes an inlet section 211 and a diffuser section 212 that are interconnected. The diffuser section 212 is connected to the root end 2311 of the diffuser channel 23. The inlet section 211 includes at least two inlets 213, which are used to communicate with an external liquid pump. The outlet channel 22 includes an outlet 221. The inlets 213 and the outlet 221 are respectively opened on both sides of the substrate 2 along the length direction of the first projection. Specifically, each inlet 213 is connected to a liquid pump, which continuously pumps coolant into the inlet 213. In this embodiment, the flow rate of each inlet 213 can be adjusted according to the output power of each liquid pump. For example, when it is necessary to increase the flow rate of coolant in the substrate 2, the output power of one or more liquid pumps can be increased to increase the flow rate of the corresponding inlet 213, thereby increasing the flow rate of coolant in the substrate 2. The flow rate of coolant in each inlet 213 can be controlled individually, making the flow rate control of coolant in substrate 2 more flexible and suitable for various working conditions.

[0058] The substrate 2 is made of one of aluminum alloy, copper, and copper alloy. In one embodiment of this invention, the substrate 2 is made of aluminum alloy. The raw material cost of aluminum alloy is only about one-third that of copper, and the thermal conductivity of aluminum alloy is only lower than that of copper, giving it the advantage of high thermal conductivity. At the same time, aluminum alloy has the advantage of high formability, allowing complex flow channels to be formed in a single process. Therefore, using aluminum alloy as the substrate 2 material in this embodiment enables the substrate 2 to simultaneously possess the advantages of high thermal conductivity, high formability, and low cost.

[0059] This utility model also proposes a battery temperature control structure, which includes a liquid cooling plate 1000. The specific structure of the liquid cooling plate 1000 is as described in the above embodiments. Since this battery temperature control structure adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be described in detail here. Please refer to [link to relevant documentation]. Figure 6 The battery temperature control structure also includes a battery panel 2000 and a phase change interlayer 3000. The two sides of the phase change interlayer 3000 are respectively bonded to the battery panel 2000 and the substrate 2; or, the two sides of the phase change interlayer 3000 are respectively bonded to the battery panel 2000 and the cover plate 1. The material of the phase change interlayer 3000 is an expanded graphite-paraffin composite phase change material, in which the mass fraction of expanded graphite is 15% to 20%. The thickness of the phase change interlayer 3000 can be adjusted according to the actual heat dissipation requirements of the battery panel 2000. In this embodiment, the thickness of the phase change interlayer 3000 is 0.5 mm to 3 mm. The phase change interlayer 3000 can form a low thermal resistance thermal path between the battery panel 2000 and the liquid cooling plate 1000. The phase change interlayer 3000 can absorb the instantaneous high heat generated by the battery panel 2000 during fast charging or high-rate discharging through phase change, thereby slowing down the heating rate of the battery panel 2000. After absorbing heat, the heat in the phase change interlayer 3000 can be rapidly transferred to the liquid cooling plate 1000, thereby avoiding the risk of thermal runaway caused by the complete liquefaction of the phase change material. Furthermore, the phase change interlayer 3000 can closely adhere to the solar panel 2000 and the liquid cooling plate 1000, dispersing localized hot spots in the solar panel 2000. Specifically, the heat in these localized hot spots is first transferred to the phase change interlayer 3000, which can then evenly distribute and conduct this heat to the liquid cooling plate 1000, thereby improving the heat exchange efficiency in the localized hot spot areas and further balancing the temperature of the solar panel 2000.

[0060] In one embodiment of this utility model, the battery temperature control structure further includes a controller and a temperature sensor and a liquid pump communicatively connected to the controller. The temperature sensor is used to monitor the temperature information of the surface of the battery panel 2000, the controller is used to receive the temperature information, and the liquid pump is connected to the liquid inlet channel 21. Multiple temperature sensors are arranged in a matrix, enabling real-time monitoring of temperature changes in multiple areas of the battery panel 2000 surface. The controller employs a fuzzy PID-neural network controller. Based on the temperature data fed back from the temperature sensors, the fuzzy PID can calculate the basic flow rate V1 required by the liquid pump in real time, while the neural network can dynamically predict the heat generation trend of the battery panel 2000 over a future period, thereby outputting a dynamically compensated flow rate V2. Finally, the controller controls the flow rate of the liquid pump inputting coolant into the liquid cooling plate 1000 to be (V1+V2). This achieves the effect of dynamically controlling the coolant input flow rate based on temperature feedback, thereby enabling precise temperature control of the battery panel 2000 and preventing the liquid pump from constantly operating at high speed, thus reducing the pump's energy consumption.

[0061] The above description is merely an exemplary embodiment of the present utility model and does not limit the scope of protection of the present utility model. Any equivalent structural transformations made based on the technical concept of the present utility model and the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the scope of protection of the present utility model.

Claims

1. A liquid-cooled plate, characterized in that, include: Cover plate; A substrate having an inlet channel, an outlet channel, and a diffusion channel, wherein the two ends of the diffusion channel are respectively connected to the inlet channel and the outlet channel, and a cover plate is fixedly installed on the substrate. The diffusion channel includes two sets of bifurcated fractal channels and multiple straight channels; Definition: The projection of the substrate onto the cover plate is the first projection; The first projection is rectangular in shape. The two sets of bifurcation flow channels are symmetrically arranged along the central axis of the length direction of the first projection. Each bifurcation flow channel includes a root end and multiple ends. One root end is connected to the inlet flow channel, and the other root end is connected to the outlet flow channel. The two ends of the straight flow channel are respectively connected to two symmetrically arranged ends in the two sets of bifurcation flow channels. The bifurcation fractal flow channel includes a root flow channel, a primary flow channel, a secondary flow channel, and a tertiary flow channel. The root flow channel is connected to two primary flow channels, each primary flow channel is connected to two secondary flow channels, and each secondary flow channel is connected to two tertiary flow channels. The root flow channel, the primary flow channel, the secondary flow channel, and the tertiary flow channel form a bifurcation fractal structure. The root end is located at the end of the root channel away from the first-stage channel, and the end end is located at the end of the tertiary channel away from the second-stage channel; Definition: The widths of the root channel, the first-stage channel, the second-stage channel, and the third-stage channel are D1, D2, D3, and D4, respectively; Then, D4 / D3=[0.6, 1], D3 / D2=[0.6, 1], D2 / D1=[0.6, 1]; Definition: The angle between the primary flow channel and the root flow channel is α1, the angle between the secondary flow channel and the primary flow channel is α2, and the angle between the tertiary flow channel and the secondary flow channel is α3; Then α1, α2 and α3 are all 150°.

2. The liquid cooling plate as described in claim 1, characterized in that, The number of diffusion channels is at least two, and the at least two diffusion channels are arranged in parallel along the length direction of the first projection.

3. The liquid cooling plate as described in claim 1, characterized in that: the lengths of the root channel, the primary channel, the secondary channel, and the tertiary channel are defined as L1, L2, L3, and L4, respectively; Then, L4 / L3=[0.6, 1], L3 / L2=[0.6, 1], L2 / L1=[0.6, 1].

4. The liquid cooling plate as described in claim 2, characterized in that, The liquid inlet channel includes an inlet section and a diffusion section that are interconnected, and the diffusion section is connected to the root end of the diffusion channel. The liquid inlet section includes at least two liquid inlets, which are used to communicate with an external liquid pump; The liquid outlet channel includes a liquid outlet, and the liquid inlet and the liquid outlet are respectively opened on both sides of the substrate along the length direction of the first projection.

5. The liquid cooling plate as described in claim 1, characterized in that, The substrate is made of aluminum alloy.

6. A battery temperature control structure, characterized in that, The battery temperature control structure includes a liquid cooling plate as described in any one of claims 1 to 5, and further includes a battery plate and a phase change interlayer; The two sides of the phase change interlayer are respectively bonded to the solar panel and the substrate; Alternatively, the two sides of the phase change interlayer are respectively attached to the battery panel and the cover plate.

7. The battery temperature control structure as described in claim 6, characterized in that, The battery temperature control structure also includes a controller and a temperature sensor and a liquid pump that are communicatively connected to the controller. The temperature sensor is used to monitor the temperature information of the surface of the battery panel, the controller is used to receive the temperature information, and the liquid pump is connected to the liquid inlet channel.

Images