Liquid cooling plate with double liquid cooling structures and preparation method thereof

Abstract

The invention discloses a liquid cooling plate with a double liquid cooling structure and a preparation method thereof, and belongs to the technical field of battery system heat dissipation, the liquid cooling plate comprises a water inlet, a water outlet and two symmetrically arranged liquid cooling flow channels, each liquid cooling flow channel comprises a plurality of longitudinal flow channels and a plurality of groups of transverse flow channels, the longitudinal flow channels and the transverse flow channels are sequentially and alternately connected in series to form a series connection structure, each group of transverse flow channels comprises at least two parallel transverse branch channels, the water inlet and the water outlet are located at two ends of the same side of the liquid cooling plate, and the two liquid cooling flow channels are arranged in a manner that the middle sections are located in the middle of the liquid cooling plate and the two sides are close to the edges; and the two liquid cooling flow channels share the water inlet and the water outlet. The invention solves the technical problems of uneven heat dissipation and limited heat dissipation efficiency caused by the existing single-loop flow channel design, has the remarkable advantages of high heat dissipation efficiency and strong stability, and is particularly suitable for heat dissipation application scenarios of 104s lithium batteries.

Description

Technical Field

[0001] The present invention belongs to the technical field of battery system heat dissipation, and particularly relates to a liquid cooling plate with a double liquid cooling structure and a preparation method thereof. Background Art

[0002] Battery technology has developed rapidly, and more and more power battery packs and large energy storage battery packs are applied in fields such as electric vehicles and energy storage. In power battery packs and large energy storage battery packs, the charging current and the discharging current are relatively large. Therefore, the heat generated by the battery cells during use is also relatively large, resulting in an increase in the temperature of the entire battery pack. When the temperature rises to a certain value, it is easy to shorten the service life of electrical components such as battery cells and the slave control of the battery management system, and reduce the performance, and even thermal runaway may occur.

[0003] To address this problem, the prior art mostly uses a liquid cooling plate with a single-loop flow channel design to dissipate heat from the battery cell module. The single-loop flow channel design has the advantages of simple structure, low manufacturing difficulty, low cost, and easy maintenance. Its structural simplicity is reflected in reducing the complexity and intersection points of the flow channels, making the manufacturing process smoother. At the same time, the clear layout of the water inlet and outlet positions makes the flow path of the cooling liquid clear, facilitating management and monitoring. Under appropriate flow rate and pressure, the single-loop flow channel design can provide a stable heat dissipation effect, ensuring that the battery or electronic components maintain an appropriate temperature during operation. However, in practical applications, the single-loop flow channel design also has the following technical problems: 1. Since the flow path of the cooling liquid in the liquid cooling plate is relatively single, a large temperature difference is generated in different regions of the liquid cooling plate, especially when the cooling liquid flows through multiple battery cell modules in sequence, thus affecting the uniformity of heat dissipation.

[0004] 2. Since the flow path of the cooling liquid in the liquid cooling plate is relatively single, it may not be able to fully exchange heat with the heat sources in the liquid cooling plate, and it is difficult to ensure that each battery cell module can obtain sufficient heat dissipation, resulting in poor overall heat dissipation efficiency.

[0005] Therefore, it is necessary to explore an innovative liquid cooling plate flow channel design structure to improve the safety and stability of the battery pack. Summary of the Invention

[0006] The purpose of the present invention is to solve the above problems existing in the prior art, and provides a liquid cooling plate with a double liquid cooling structure and a preparation method thereof. The present invention effectively solves the technical problems of uneven heat dissipation and limited heat dissipation efficiency caused by the existing single-loop flow channel design through two symmetrically arranged liquid cooling channels, making the flow of the cooling liquid in the liquid cooling plate more uniform and stable, thereby ensuring that the battery or electronic components maintain an appropriate temperature during operation, effectively preventing performance degradation or damage caused by overheating, and further extending the service life of the battery or electronic components.

[0007] To achieve the above object, the technical solution adopted by the present invention is as follows: On the one hand, the present invention provides a liquid cooling plate with a dual liquid cooling structure, including a water inlet, a water outlet, and two symmetrically arranged liquid cooling channels. Each liquid cooling channel includes a plurality of longitudinal channels and multiple groups of transverse channels. The longitudinal channels and the transverse channels are alternately connected in series in sequence. Each group of transverse channels includes at least two parallel transverse branches. The water inlet and the water outlet are both located at the two ends on the same side of the liquid cooling plate. The two liquid cooling channels are both arranged in such a way that the middle section is located in the middle of the liquid cooling plate and the two sides are close to the edge, and the two liquid cooling channels share the water inlet and the water outlet.

[0008] The transverse channels in the liquid cooling channels include a first transverse channel, a second transverse channel, a third transverse channel, and a fourth transverse channel. In the two liquid cooling channels, the first transverse channels are respectively located on the upper side and the lower side of the liquid cooling plate. The second transverse channel is located in the middle of the liquid cooling plate. The third transverse channel and the fourth transverse channel are both located between the first transverse channel and the second transverse channel. The third transverse channel is close to the second transverse channel, and the fourth transverse channel is close to the first transverse channel. The first transverse channels are both connected to the water inlet, the fourth transverse channels are both connected to the water outlet, and each longitudinal channel is vertically connected between multiple groups of transverse channels.

[0009] The first transverse channel includes left and right sections of channels, and the left and right sections of channels are connected by a transverse pipe and form an avoidance notch.

[0010] The liquid cooling plate includes a cover plate and a channel plate both in a square shape. The channel plate is provided with channels, and the liquid cooling channels are formed by welding the cover plate to the channel plate. The water inlet and the water outlet are both arranged at the upper and lower ends on the same side of the cover plate.

[0011] Positioning and installation holes are provided between the third transverse channel and the fourth transverse channel, between the second transverse channels of the two liquid cooling channels, and at the avoidance notch. The cover plate and the channel plate form a pre-connection structure of the liquid cooling plate through the positioning and installation holes.

[0012] The depth of the channel is 4 - 4.5 mm, and the width is 20 - 25 mm.

[0013] On the other hand, the present invention also provides a method for preparing a liquid cooling plate with a dual liquid cooling structure, including the following steps: Step 1: Cut out the cover plate blank and the channel plate blank, process positioning and installation holes on the cover plate blank and the channel plate blank, and process the water inlet and the water outlet at the two ends on the same side of the cover plate blank; Step 2: Use a grinding machine to grind the surfaces of the cover plate blank and the runner plate blank to remove the oxide film and surface defects, and use a laser irradiation device to irradiate the surfaces of the cover plate blank and the runner plate blank to promote surface alloying of the cover plate blank and the runner plate blank. After the treatment, the pretreated cover plate blank and the runner plate blank are obtained; Step 3: Spray aluminum alloy powder on the surfaces of the pretreated cover plate blank and the runner plate blank through a cold spraying process to obtain a cover plate and a runner plate with an aluminum alloy coating; Step 4: Use a stamping machine to stamp on the runner plate to control the formation of channels on the runner plate, and control the stamping tonnage between 2300 - 2700 tons; the channels include two symmetrically arranged liquid cooling channels, and each liquid cooling channel includes a plurality of longitudinal channels and multiple groups of transverse channels. The longitudinal channels and the transverse channels are alternately connected in sequence. Each group of transverse channels includes at least two parallel transverse branch channels. Both liquid cooling channels are arranged in such a way that the middle section is located in the middle of the runner plate and both sides are close to the edge, and the two liquid cooling channels share a water inlet and a water outlet; Step 5: Coat a brazing flux on the brazing connection part of the runner plate, and install the cover plate with an aluminum alloy coating on the runner plate with channels through the positioning and mounting holes to form a pre - connected liquid cooling plate; Step 6: Place the pre - connected liquid cooling plate in a brazing furnace, control the temperature of the brazing furnace between 610 - 625 °C, and maintain brazing for 8 - 12 minutes within this temperature range, and then control the brazing furnace to cool down for 30 minutes to obtain a brazed - connected liquid cooling plate; Step 7: Spray an insulating powder on the surface of the brazed - connected liquid cooling plate, and the thickness of the insulating powder spraying is 200 - 300 microns to obtain a liquid cooling plate with electrical isolation.

[0014] Preferably, in the above Step 2, the conditions for the laser irradiation treatment are: the irradiation wavelength is 1064 nm, the power density is 10^4 - 10^5 W / cm², the scanning speed is 0.5 - 2 m / min, and the single - channel irradiation duration is 50 - 200 ms.

[0015] Preferably, in the above Step 3, the spraying amount of the aluminum alloy powder on the surfaces of the cover plate blank and the runner plate blank is 8 - 12 g / m².

[0016] Preferably, in the above Step 4, the depth of the channel is 4 - 4.5 mm and the width is 20 - 25 mm.

[0017] The advantages of adopting the present invention are: 1. A liquid cooling plate with a dual liquid cooling structure provided by the present invention. First, two liquid cooling channels are symmetrically arranged on the liquid cooling plate, reducing the resistance of the cooling liquid in the channels, making the flow of the cooling liquid in the liquid cooling plate more stable, reducing adverse effects such as eddy currents and turbulence, improving the stability and reliability of heat dissipation of the liquid cooling plate. More importantly, the two symmetrically arranged liquid cooling channels can evenly disperse the coolant flow to the target flow path, helping to reduce the temperature difference between different regions of the liquid cooling plate, enabling the cooling liquid to exchange heat more fully with the heat sources inside the liquid cooling plate.

[0018] Second, the longitudinal channels and the transverse channels are alternately connected in sequence to form a meandering structure layout to form the liquid cooling channels. This design increases the flow path and heat dissipation area of the coolant, thereby improving the heat dissipation efficiency.

[0019] Third, each group of transverse channels includes at least two parallel transverse branches. This parallel design maximally expands the heat exchange area in contact with the battery module within the limited space of the liquid cooling plate, further enhancing the heat dissipation efficiency.

[0020] Fourth, both of the two liquid cooling channels are arranged in such a way that the middle sections are located in the middle of the liquid cooling plate and the two sides are close to the edges, and the two liquid cooling channels share the water inlet and the water outlet. Thus, according to the flow path and flow trend of the coolant in the liquid cooling channels, when the coolant is introduced through the water inlet and directly guided to the two edges of the liquid cooling plate, the coolant is still in a relatively low temperature state at this time, and then the coolant diffuses towards the middle area of the liquid cooling plate. This design ensures that the coolant can preferentially and effectively cover a large area of key heat dissipation areas on the liquid cooling plate, achieving efficient and uniform cooling coverage. This layout not only improves the heat dissipation efficiency and uniformity, realizes efficient heat transfer and dissipation, but also greatly enhances the accuracy of battery module temperature control, effectively avoiding local overheating, thereby prolonging the service life of the battery and optimizing the thermal management performance of the battery system in all aspects.

[0021] Fifth, since both the water inlet and the water outlet are located at both ends on the same side of the liquid cooling plate, this design makes the connection and maintenance of the cooling system more convenient. When it is necessary to repair or replace the coolant, the operator can more easily access these interfaces.

[0022] In summary, for the liquid cooling plate with a dual liquid cooling structure provided by the present invention, compared with the existing single-loop flow channel technology, by adopting a design of two symmetrically arranged liquid cooling flow channels and combining the layout of the water inlet and the water outlet, the flow of the cooling liquid inside the liquid cooling plate becomes more uniform and stable. This design not only significantly improves the flow efficiency of the coolant, but also effectively increases the heat exchange area, thus realizing the efficient transfer and dissipation of heat. This effectively solves the technical problems such as uneven heat dissipation and limited heat dissipation efficiency existing in the existing single-loop flow channel design. While ensuring that the liquid cooling plate can provide a uniform temperature cooling effect, this design also ensures that the battery or electronic components can maintain a safe, suitable and stable temperature environment during operation, effectively avoiding the risk of performance degradation or damage caused by overheating, and thus significantly extending the service life of the battery or electronic components.

[0023] 2. The liquid cooling plate with a dual liquid cooling structure provided by the present invention forms multiple groups of transverse flow channels through the first transverse flow channel, the second transverse flow channel, the third transverse flow channel and the fourth transverse flow channel, and the layout of the liquid cooling flow channels is formed by the respective longitudinal flow channels being vertically connected between the multiple groups of transverse flow channels. During the entire liquid cooling process, based on the symmetrical setting of the two liquid cooling flow channels, the coolant realizes uniform distribution and efficient flow through the first transverse flow channel, the second transverse flow channel, the third transverse flow channel and the fourth transverse flow channel in the two liquid cooling flow channels. The liquid cooling plate can efficiently absorb, transfer and dissipate heat, greatly improving the temperature control accuracy and heat dissipation efficiency of the object to be cooled.

[0024] 3. The liquid cooling plate with a dual liquid cooling structure provided by the present invention forms the structure of the liquid cooling flow channels by arranging channels on the flow channel plate and welding the cover plate to the flow channel plate. Thus, the cover plate and the flow channel plate are hermetically connected to enclose the channels, ensuring the sealing performance of the liquid cooling plate, avoiding coolant leakage, and guaranteeing the sealing and safety of the overall structure of the liquid cooling plate.

[0025] 4. The liquid cooling plate with a dual liquid cooling structure provided by the present invention has a structure in which the first transverse flow channel is divided into left and right sections and connected by a transverse pipe to form an avoidance notch, which not only saves space, but also realizes better adaptability of the liquid cooling plate to the shape of the heat source and improvement of the heat dissipation efficiency, having structural flexibility and high heat dissipation performance; at the same time, positioning and installation holes are provided between the third transverse flow channel and the fourth transverse flow channel, between the second transverse flow channels of the two liquid cooling flow channels and at the avoidance notch, realizing the precise positioning and overall structural stability of the liquid cooling plate during installation, having installation convenience and structural reliability.

[0026] 5. The liquid cooling plate with a dual liquid cooling structure provided by the present invention has the channel depth designed to be 4 - 4.5 mm and the width designed to be 20 - 25 mm. Combining with the symmetrical layout of the two-way liquid cooling channels of the present invention, the cooling liquid maintains an appropriate flow rate in the channels, neither too fast nor too slow. This can avoid the increase in fluid resistance caused by too fast a flow rate and the reduction in heat dissipation efficiency caused by too slow a flow rate. The channel width of 20 - 25 mm and the channel depth of 4 - 4.5 mm can balance the flow rate and resistance to a certain extent and improve the heat dissipation efficiency.

[0027] Through experimental tests and CFD simulation analysis, it is confirmed that under the condition of a standard ambient temperature of 25°C, the experiment adopted a charge-discharge rate of 0.5C for testing to ensure that the test conditions conform to the actual application scenario. During the test, the inlet temperature of the coolant was controlled at 18°C, and the inlet flow rate was maintained at 10 L / min to ensure the consistency and accuracy of the test. The experiment followed the strict industry standard of GB / T36276 - 2023 and conducted charge-discharge performance tests on the battery pack. During the test, the applicant used large-capacity battery cells with a specification of 314 Ah and formed a battery pack containing 104 battery cells to simulate the high energy density requirements in actual use. The results show that even in such a high energy density battery pack, the liquid cooling plate can still effectively control the maximum temperature of the battery pack below 38°C, and the temperature difference between the battery cells is only 2.1°C.

[0028] Under the same test conditions, when the ambient temperature is increased to 45°C, the maximum temperature of the battery pack is below 48°C, and the temperature difference between the battery cells is only 2.2°C. When the ambient temperature is increased by 20°C, the increase in the maximum temperature of the battery pack is less than 10°C, and the temperature difference only increases by 0.1°C. The design advantage of this channel structure is obvious, far lower than the potential thermal runaway risk temperature, ensuring the safe operation of the battery system.

[0029] Comparing the two groups of tests, the temperature difference within the battery pack only changes from 2.1°C to 2.2°C. The extremely small temperature difference change indicates that the liquid cooling plate of the present invention achieves a high degree of uniformity during the heat dissipation process, avoiding local overheating or insufficient cooling, thereby extending the service life of the battery and improving the overall performance of the system.

[0030] In summary, the liquid cooling plate of the present invention, with its optimized channel design, demonstrates excellent thermal management capabilities and temperature uniformity in the experiment, providing reliable heat dissipation protection for high-performance battery packs.

[0031] 6. In the method for preparing a liquid cooling plate with a dual liquid cooling structure provided by the present invention, the beneficial effects are: (1) The preparation method of the present invention irradiates the cover plate blank and the flow channel plate blank with a laser. A laser device with a wavelength of 1064 nm is selected. This wavelength is highly compatible with the keyhole effect of aluminum materials, and the corresponding industrial equipment has a high maturity. During the laser irradiation process, the power density of the laser device is controlled between 10^4 - 10^5 W / cm², the scanning speed is between 0.5 - 2 m / min, the single-pass irradiation duration is 50 to 200 ms. When the spot diameter is 0.2 to 0.5 mm, the total duration of the entire irradiation process is strictly controlled within 0.5 to 2 seconds. Such a treatment process promotes surface alloying, reduces residual stress, and at the same time obtains a surface to be treated with a high degree of cleanliness. It not only significantly improves the material properties of the liquid cooling plate but also lays a solid foundation for its subsequent processing and assembly work, showing obvious advantages in process accuracy and surface quality optimization.

[0032] (2) The preparation method of the present invention sprays aluminum alloy powder on the surface of the pretreated cover plate blank and flow channel plate blank through a cold spraying process, and controls the spraying amount to be 8 - 12 grams per square meter, which improves the bonding strength between the aluminum alloy powder and the surfaces of the cover plate blank and the flow channel plate blank respectively, making the cover plate and the flow channel plate after the cold spraying process have good corrosion resistance, high density, and low porosity.

[0033] (3) The preparation method of the present invention punches on the flow channel plate with a punching machine, and controls the punching tonnage between 2300 - 2700 tons to ensure good forming effect of the channels, thereby ensuring that the liquid cooling plate has excellent heat exchange performance.

[0034] (4) The preparation method of the present invention precisely sets the brazing temperature range of the brazing furnace to be 610°C - 625°C, and can be flexibly adjusted according to different requirements of the liquid cooling plate and channel design. Appropriate heating can reduce the viscosity of the brazing filler metal, enhance fluidity and wettability, making the liquid brazing filler metal more likely to fill the joint through capillary action, ensuring the weld seam is dense. However, if the temperature exceeds 630°C, it may cause excessive flow and even loss of the brazing filler metal, resulting in poor weld seam filling or porosity formation, and the flow channel plate and the cover plate may be melted and eroded due to local overheating, reducing the joint strength.

[0035] Therefore, by maintaining brazing for 8 - 12 minutes within the range of 610 - 625°C and then controlling the cooling for 30 minutes, a liquid cooling plate with brazed connection can be obtained. This brazing process and connection method show excellent sealing performance, significantly improving the connection quality and sealing effect between the cover plate and the flow channel plate, and having the characteristics of strong process adaptability, reliable connection, stable structure, and excellent performance. At the same time, this process effectively improves production efficiency and product quality.

[0036] (5) By implementing an insulation spraying treatment on the liquid cooling plate after brazing connection and precisely controlling the thickness of the sprayed coating between 200 and 300 microns, this measure can effectively prevent current leakage or short - circuit phenomena. The insulation sprayed coating builds a solid barrier between the liquid cooling plate and the battery pack housing, significantly reducing the transfer of unnecessary heat to the external environment, thereby improving the thermal management efficiency of the liquid cooling system. At the same time, this treatment also significantly enhances the overall insulation performance of the system, providing strong guarantee for the safe and stable operation of the liquid cooling plate. Brief Description of the Drawings

[0037] Figure 1 is a structural schematic diagram of the present invention; Figure 2 is a structural schematic diagram of the cover plate in the present invention; Figure 3 is a cross - sectional structural schematic diagram of the liquid cooling flow channel formed by the cover plate and the flow channel plate in the present invention.

[0038] The reference numerals in the figure are: 1, water inlet; 2, water outlet; 21, brazing connection part; 3, liquid cooling flow channel; 4, longitudinal flow channel; 5, transverse flow channel; 50, transverse branch channel; 51, first transverse flow channel; 52, second transverse flow channel; 53, third transverse flow channel; 54, fourth transverse flow channel; 510, horizontal pipe; 6, positioning and installation hole; 7, cover plate; 8, flow channel plate; 80, channel; 9, liquid inlet nozzle joint; 10, liquid outlet nozzle joint; 11, outlet branch; 12, inlet branch A; 13, inlet branch B. Detailed Embodiment

[0039] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. For the convenience of description, the description of the relative positional relationship of each component is based on the layout of the drawings in the specification. For example, the positional relationships such as front, rear, up, down, left, and right are determined according to the layout direction of the drawings in the specification.

[0040] Embodiment 1 The present invention provides a liquid cooling plate with a dual - liquid - cooling structure, as Figure 1 shown, including a water inlet 1, a water outlet 2, and two symmetrically arranged liquid cooling flow channels 3. The water inlet 1 and the water outlet 2 are respectively connected to the coolant circulation system. Taking Figure 1Taking the shown direction as an example, the two-way liquid cooling channels 3 are symmetrically arranged on the liquid cooling plate with the transverse axis of the liquid cooling plate as the center, which can evenly disperse the flow direction of the cooling liquid to the target flow path, helping to reduce the temperature difference between regions of the liquid cooling plate, enabling the cooling liquid to more fully exchange heat with the heat sources inside the liquid cooling plate. During the heat dissipation process of the liquid cooling plate, at the water inlet 1, the cooling liquid is pumped into the interior of the liquid cooling plate body and exchanges heat with the object to be cooled through the liquid cooling channels 3; while at the water outlet 2, the cooling liquid that has absorbed heat is discharged from the liquid cooling plate body and then transported to other parts of the heat dissipation system (such as a radiator or a heat exchanger) for cooling treatment. In this process, the water inlet 1 and the water outlet 2 play a crucial role in connecting the preceding and the following, ensuring the continuity and stability of the heat dissipation system. At the same time, by precisely controlling the flow rate and temperature of the cooling liquid, the cooling liquid inlet and outlet can also help achieve more precise and efficient heat dissipation control.

[0041] Each liquid cooling channel 3 includes a plurality of longitudinal channels 4 and multiple groups of transverse channels 5. The longitudinal channels 4 and the transverse channels 5 are alternately connected in sequence to form a series connection structure, and each group of transverse channels 5 includes at least two parallel transverse branches 50. This parallel design maximally expands the heat exchange area in contact with the battery module within the limited space of the liquid cooling plate to improve the heat dissipation efficiency.

[0042] In some embodiments, the water inlet 1 and the water outlet 2 are respectively arranged at the middle positions on the same side of the liquid cooling plate. Although this is a theoretically feasible solution, considering the current processing and manufacturing capabilities and the requirements for the sealing level, the layout shown in Figure 1-2 is adopted in this embodiment, that is: both the water inlet 1 and the water outlet 2 are located at both ends on the same side of the liquid cooling plate, specifically at the corner positions where the length direction and the width direction of the liquid cooling plate intersect. Such a design not only meets the actual requirements but also ensures the rationality of the layout.

[0043] Furthermore, the two-way liquid cooling channels 3 are both arranged in such a way that the middle section is located in the middle of the liquid cooling plate and both sides are close to the edges, and the two-way liquid cooling channels 3 share the water inlet 1 and the water outlet 2. Thus, according to the flow path and flow trend of the cooling liquid in the liquid cooling channels 3, when the cooling liquid is introduced through the water inlet 1 and directly guided to the two side edges of the liquid cooling plate (taking the Figure 1 shown direction as the transverse edges), at this time the cooling liquid still maintains a relatively low temperature state, and then the cooling liquid diffuses towards the middle area of the liquid cooling plate. This design ensures that the cooling liquid can preferentially and effectively cover a large area of key heat dissipation regions on the liquid cooling plate, achieving efficient and uniform cooling coverage. This layout not only improves the heat dissipation efficiency and uniformity, realizes the efficient transfer and dissipation of heat, but also greatly enhances the accuracy of the battery module temperature control, effectively avoiding local overheating phenomena, thereby prolonging the service life of the battery and comprehensively optimizing the thermal management efficiency of the battery system.

[0044] Embodiment 2 Based on Embodiment 1, the structure of the two-way liquid cooling channels 3 is optimized in this embodiment.

[0045] Continue to refer to Figure 1 , each group of transverse channels 5 in each liquid cooling channel 3 includes a first transverse channel 51, a second transverse channel 52, a third transverse channel 53, and a fourth transverse channel 54; in the two liquid cooling channels 3, the first transverse channels 51 are respectively located on the upper and lower sides of the liquid cooling plate, the second transverse channel 52 is located in the middle of the liquid cooling plate, the third transverse channel 53 and the fourth transverse channel 54 are both located between the first transverse channel 51 and the second transverse channel 52, the third transverse channel 53 is close to the second transverse channel 52, and the fourth transverse channel 54 is close to the first transverse channel 51; the first transverse channels 51 are both connected to the water inlet 1, the fourth transverse channels 54 are both connected to the water outlet 2, and each longitudinal channel 4 is vertically connected between multiple groups of transverse channels 5.

[0046] When the liquid cooling plate is performing heat dissipation work, the coolant enters the liquid cooling plate from the water inlet 1 and is first split into the first transverse channels 51 on the upper and lower sides of the two-way liquid cooling channels 3. In these two starting channels, the coolant begins to perform preliminary heat exchange with the object to be cooled (such as a battery module). Subsequently, the coolant flows towards the middle of the liquid cooling plate along the vertically connected longitudinal channels 4 respectively. The coolant in the upper first transverse channel 51 flows downward, while the coolant in the lower first transverse channel 51 flows upward, causing the coolant to converge towards the middle region. According to the design layout of the liquid cooling channels and the flow trend of the coolant, when the split coolant reaches the second transverse channels 52 of the two-way liquid cooling channels 3 in the middle of the liquid cooling plate respectively, it continues to perform heat exchange with the object to be cooled. Thus, the large-area contour of the liquid cooling plate is preferentially cooled, ensuring that the main heat dissipation area of the liquid cooling plate is effectively cooled first. During the flow process, the coolant continuously absorbs heat and its temperature gradually rises. Then, the coolant continues to flow along the vertically connected longitudinal channels 4 to the third transverse channel 53. Since the third transverse channel 53 is close to the second transverse channel 52, it provides additional cooling support for the middle region. In the third transverse channel 53, the coolant further performs heat exchange with the object to be cooled and the temperature continues to rise. Finally, the coolant enters the fourth transverse channel 54 along the vertically connected longitudinal channels 4. In the fourth transverse channel 54, the coolant collects all the heat released by the object to be cooled and is discharged from the liquid cooling plate through the water outlet 2, and then enters other parts of the heat dissipation system for cooling treatment. Therefore, the entire liquid cooling channel 3 forms a closed-loop liquid cooling circuit in cooperation with the coolant circulation system, and the coolant continuously circulates in this circuit to achieve continuous heat dissipation of the object to be cooled.

[0047] During the entire liquid cooling process, based on the symmetric arrangement of the two liquid cooling channels 3, the coolant realizes uniform distribution and efficient flow through the first transverse channel 51, the second transverse channel 52, the third transverse channel 53, and the fourth transverse channel 54 in the two liquid cooling channels 3. The liquid cooling plate can efficiently absorb, transfer, and dissipate heat, ensuring the temperature control accuracy and heat dissipation efficiency of the object to be cooled.

[0048] Theoretically, the sum of the coolant temperatures in the two symmetrically arranged liquid cooling channels 3 is the same. When applied to the heat dissipation of the battery modules in the 104s lithium battery box, the average temperature performance of the entire battery module is excellent. It can not only improve the heat dissipation efficiency but also significantly reduce the temperature difference of the battery modules, ensure uniform temperature of the battery pack, extend the battery service life, and improve the system performance.

[0049] Preferably, an inlet branch A12 is provided on the upper side of the liquid cooling plate, an inlet branch B13 and an outlet branch 11 are provided on the right side of the liquid cooling plate, and the inlet branch B13 is located on the right side of the outlet branch 11. The first transverse channel 51 on the upper side of the liquid cooling plate is connected to the water inlet 1 through the inlet branch A12, the first transverse channel 51 on the lower side of the liquid cooling plate is connected to the water inlet 1 through the inlet branch B13, and the fourth transverse channels 54 in the two liquid cooling channels 3 are converged and connected to the water outlet 2 through the outlet branch 11.

[0050] Furthermore, as Figure 2-3 shown, the liquid cooling plate includes a cover plate 7 and a flow channel plate 8 both in a square shape. A channel 80 is provided on the flow channel plate 8, and the liquid cooling channel 3 is formed by welding the cover plate 7 to the flow channel plate 8. The water inlet 1 and the water outlet 2 are both arranged at the upper and lower ends on the same side of the cover plate 7. A liquid inlet nozzle joint 9 and a liquid outlet nozzle joint 10 are vertically installed on the cover plate 1. The liquid inlet nozzle joint 9 is communicated with the water inlet 1, and the liquid outlet nozzle joint 10 is communicated with the water outlet 2. The cover plate 7 and the flow channel plate 8 are both made of aluminum or copper materials, and preferably, they are hermetically connected through a brazing process to ensure the sealing performance.

[0051] In addition, the first transverse channel 51 includes two left and right sections of channels, and the two left and right sections of channels are connected by a transverse pipe 510 and form an avoidance notch. Positioning and installation holes 6 are provided between the third transverse channel 53 and the fourth transverse channel 54, between the second transverse channels 52 of the two liquid cooling channels 3, and at the avoidance notch. The positioning and installation holes 6 are used for positioning during the processing of the liquid cooling plate, so that the cover plate 7 and the flow channel plate 8 form a pre-connected structure of the liquid cooling plate through the positioning and installation holes 6, and at the same time, they also serve as installation reference holes for other connecting components of the object to be cooled.

[0052] Furthermore, the depth of the groove 80 is 4-4.5 mm and the width is 20-25 mm. In the liquid cooling channel 3, a heat transfer enhancement structure such as ribs and spoilers is designed to transform the coolant from laminar flow to turbulent flow, improve the heat transfer coefficient and reduce thermal resistance. The heat transfer enhancement structure can be processed by a stamping process, which can improve the heat dissipation performance and maintain the integrity of the channel structure.

[0053] Example 3 The present invention also provides a method for preparing the liquid cooling plate design structure of Example 1 and Example 2, and the preparation method specifically comprises the following steps: Step 1: Cut the cover plate blank and the runner plate blank according to the set size and shape of the liquid cooling plate, process the positioning and mounting holes 6 on the cover plate blank and the runner plate blank, and process the water inlet 1 and the water outlet 2 at both ends of the same side of the cover plate blank.

[0054] The cover plate blank and runner plate blank preferably use aluminum alloy AL-3003 material as the base material because it has good mechanical properties, thermal conductivity and lightweight characteristics, which meets the dual needs of weight reduction and heat dissipation in fields such as electric vehicles.

[0055] Step 2: The cut cover plate blank and runner plate blank need to be initially cleaned to remove surface oil and impurities. Then, the cover plate blank and runner plate blank are polished by a grinder. The purpose of polishing the surface of the cover plate blank and runner plate blank is to remove the oxide film and its surface defects. Then, the cover plate blank and runner plate blank are irradiated with a laser to promote surface alloying. After the treatment is completed, the pre-treated cover plate blank and runner plate blank are obtained.

[0056] Among them, the cover plate blank and the runner plate blank are treated with laser irradiation, and a laser device with a wavelength of 1064nm is selected. This wavelength is highly compatible with the keyhole effect of aluminum, and the corresponding industrial equipment is relatively mature. During the laser irradiation process, the power density of the laser equipment is controlled to be between 10^4-10^5 W / cm², the scanning speed is between 0.5-2 m / min, and the single-channel irradiation time is 50 to 200 ms. When the spot diameter is 0.2 to 0.5 mm, the total duration of the entire irradiation process is strictly controlled within 0.5 to 2 seconds. This treatment process promotes surface alloying, reduces residual stress, and obtains a higher degree of cleanliness of the treated surface. It not only significantly improves the material properties of the liquid cooling plate, but also lays a solid foundation for its subsequent processing and assembly work, and shows obvious advantages in process accuracy and surface quality optimization.

[0057] Step 3: Feed the pre-treated cover plate blank and runner plate blank into the cold spraying equipment, and spray aluminum alloy powder on the surfaces of the pre-treated cover plate blank and runner plate blank through the cold spraying process to obtain a cover plate and a runner plate with aluminum alloy coatings. During the cold spraying process, control the spraying amount of the aluminum alloy powder sprayed on the surfaces of the cover plate blank and the runner plate blank by the cold spraying equipment to be 8-12 g / m². When the powder particles impact the surfaces of the cover plate blank and the runner plate blank, they undergo plastic deformation to ensure the tight bonding of the aluminum alloy powder to the cover plate blank and the runner plate blank respectively.

[0058] Step 4: Feed the runner plate blank after cold spraying treatment into a stamping machine, and perform stamping on the runner plate 8 by the stamping machine. Control the formation of the channel 80 on the runner plate 8, and control the stamping tonnage to be between 2300-2700 tons to ensure good forming of the channel 80, thereby ensuring the heat exchange performance of the liquid cooling plate. The depth of the channel 80 formed on the runner plate 8 by stamping is 4-4.5 mm, and the width is 20-25 mm.

[0059] The channel 80 includes two symmetrically arranged liquid cooling channels. Each liquid cooling channel includes a plurality of longitudinal channels and multiple groups of transverse channels. The longitudinal channels and the transverse channels are alternately connected in sequence. Each group of transverse channels includes at least two parallel transverse branch channels. Both liquid cooling channels are arranged in such a way that the middle section is located in the middle of the runner plate 8 and both sides are close to the edge, and the two liquid cooling channels share the water inlet 1 and the water outlet 2.

[0060] Step 5: Clean the stamped runner plate 8 to remove the oil stains and impurities on the surface. Then, apply a brazing flux to the brazing connection part 21 of the runner plate 8, as Figure 3 shown. The brazing connection part 21 is located in the raised position area between the channels 80 and the channels 80. Then, install the cover plate 7 with an aluminum alloy coating on the runner plate 8 with the channel 80 through the positioning mounting holes 6 to form a pre-connected liquid cooling plate.

[0061] Step 6: Place the pre-connected liquid cooling plate in a brazing furnace for brazing treatment. In the brazing furnace, the liquid cooling plate is first heated up, and the expected heating-up time is 25 minutes. Control the temperature of the brazing furnace to be between 610-625 °C, and maintain this temperature range for brazing for 8-12 minutes. Then, control the brazing furnace to cool down for 30 minutes to obtain a brazed liquid cooling plate.

[0062] In this step, the brazing temperature range of the brazing furnace is precisely set to 610°C - 625°C, and it can be flexibly adjusted according to different requirements of the liquid cooling plate and channel design. Appropriate heating can reduce the viscosity of the brazing filler metal, enhance fluidity and wettability, making it easier for the liquid brazing filler metal to fill the joint through capillary action and ensuring a dense weld. However, if the temperature exceeds 630°C, it may cause excessive flow or even loss of the brazing filler metal, resulting in poor weld filling or porosity formation, and the flow channel plate and cover plate may be melted and corroded due to local overheating, reducing the joint strength.

[0063] Step 7: Take out the liquid cooling plate after brazing connection from the brazing furnace, and perform an insulating powder spraying treatment on the surface of the liquid cooling plate. The thickness of the insulating powder spraying is 200 - 300 microns to obtain a liquid cooling plate with electrical isolation.

[0064] In this step, the purpose is to further ensure the thermal management efficiency and electrical safety of the liquid cooling plate. An insulating powder spraying treatment is carried out on the liquid cooling surface, and the thickness of the sprayed coating is precisely controlled between 200 and 300 microns. The existence of the insulating sprayed coating and its precisely controlled thickness provide reliable electrical isolation between the liquid cooling plate and other components of the battery pack. This layer of insulating material with a thickness of 200 to 300 microns can effectively prevent current leakage or short - circuit phenomena. It forms a barrier between the liquid cooling plate and the object to be cooled, such as the battery pack housing, reducing unnecessary heat transfer to the external environment, thereby improving the thermal management efficiency of the liquid cooling system and enhancing the overall insulation performance of the system.

[0065] In addition, taking Figure 3 the direction shown as an example, a 2 - mm - thick thermal insulation cotton is attached to the bottom of the liquid cooling plate. This thickness of thermal insulation cotton has good heat insulation effect, which can significantly reduce heat loss and ensure the efficient operation of the liquid cooling system. In the case of spraying insulating powder, the thermal insulation cotton at the bottom further reduces heat loss, ensuring that the cooling medium can more effectively absorb and carry away the heat generated by the battery when circulating in the liquid cooling plate. When the temperature at the bottom of the liquid cooling plate drops below the dew point, water vapor in the surrounding environment will condense into water droplets on the surface of the cold plate, that is, the condensation phenomenon occurs. This will not only affect the normal operation of the liquid cooling system but also may cause damage to the battery pack. The addition of thermal insulation cotton can reduce the heat dissipation at the bottom of the liquid cooling plate, thereby increasing the temperature of the cold plate surface and avoiding it dropping below the dew point, providing a more stable and reliable operating environment for the battery pack.

[0066] The above - mentioned is only the specific implementation manner of the present invention. Any feature disclosed in this specification, unless specifically described, can be replaced by other equivalent or similar - purpose alternative features; all the features disclosed, or all the steps in any method or process, except for mutually exclusive features and / or steps, can be combined in any way.

Claims

1. A liquid cooling plate with a dual liquid cooling structure, characterized in that: It includes a water inlet (1), a water outlet (2), and two symmetrically arranged liquid cooling channels (3). Each liquid cooling channel (3) includes a plurality of longitudinal channels (4) and multiple groups of transverse channels (5). The longitudinal channels (4) and the transverse channels (5) are alternately connected in series in sequence. Each group of transverse channels (5) includes at least two parallel transverse branches (50). The water inlet (1) and the water outlet (2) are both located at the two ends on the same side of the liquid cooling plate. The two liquid cooling channels (3) are both arranged in such a way that the middle section is located in the middle of the liquid cooling plate and both sides are close to the edge, and the two liquid cooling channels (3) share the water inlet (1) and the water outlet (2).

2. The liquid cooling plate with a dual liquid cooling structure according to claim 1, characterized in that: The transverse channels (5) in the liquid cooling channel (3) include a first transverse channel (51), a second transverse channel (52), a third transverse channel (53), and a fourth transverse channel (54). In the two liquid cooling channels (3), the first transverse channels (51) are respectively located on the upper side and the lower side of the liquid cooling plate. The second transverse channel (52) is located in the middle of the liquid cooling plate. The third transverse channel (53) and the fourth transverse channel (54) are both located between the first transverse channel (51) and the second transverse channel (52). The third transverse channel (53) is close to the second transverse channel (52), and the fourth transverse channel (54) is close to the first transverse channel (51). The first transverse channels (51) are both connected to the water inlet (1), the fourth transverse channels (54) are both connected to the water outlet (2), and each longitudinal channel (4) is vertically connected between multiple groups of transverse channels (5).

3. The liquid cooling plate with a dual liquid cooling structure according to claim 2, characterized in that: The first transverse channel (51) includes left and right sections of channels, and the left and right sections of channels are connected by a cross tube (510) to form an avoidance notch.

4. The liquid cooling plate with a dual liquid cooling structure according to claim 3, wherein: The liquid cooling plate includes a cover plate (7) and a channel plate (8) both in a square shape. The channel plate (8) is provided with a channel (80). The liquid cooling channel (3) is formed by welding the cover plate (7) to the channel plate (8). The water inlet (1) and the water outlet (2) are both arranged at the upper and lower ends on the same side of the cover plate (7).

5. The liquid cooling plate with a dual liquid cooling structure according to claim 4, characterized in that: Positioning and installation holes (6) are provided between the third transverse channel (53) and the fourth transverse channel (54), between the second transverse channels (52) of the two liquid cooling channels (3), and at the avoidance notch. The cover plate (7) and the channel plate (8) form a pre - connection structure of the liquid cooling plate through the positioning and installation holes (6).

6. The liquid cooling plate with a dual liquid cooling structure according to claim 5, wherein: The depth of the channel (80) is 4 - 4.5 mm, and the width is 20 - 25 mm.

7. A method for manufacturing a liquid cooling plate with a dual liquid cooling structure as described in any one of claims 1-6, characterized in that, It includes the following steps: Step 1: Cut out the cover plate blank and the channel plate blank, process the positioning and installation holes (6) on the cover plate blank and the channel plate blank, and process the water inlet (1) and the water outlet (2) at the two ends on the same side of the cover plate blank; Step 2: Use a grinding machine to polish the surfaces of the cover plate blank and the channel plate blank to remove the oxide film and surface defects, and use a laser irradiation device to irradiate the surfaces of the cover plate blank and the channel plate blank to promote surface alloying of the cover plate blank and the channel plate blank. After the treatment, obtain the pre - treated cover plate blank and channel plate blank; Step 3: Spray aluminum alloy powder on the surface of the pre-treated cover blank and runner plate blank through cold spraying process to obtain a cover (7) and a runner plate (8) with aluminum alloy coatings; Step 4: Use a stamping machine to stamp on the runner plate (8), control the runner plate (8) to form a channel (80), and control the stamping tonnage between 2300 - 2700 tons; the channel (80) includes two symmetrically arranged liquid cooling channels, each liquid cooling channel includes multiple longitudinal channels and multiple groups of transverse channels, the longitudinal channels and the transverse channels are alternately connected in sequence, each group of transverse channels includes at least two parallel transverse branch channels, both liquid cooling channels are arranged in such a way that the middle section is located in the middle of the runner plate (8) and both sides are close to the edge, and the two liquid cooling channels share a water inlet (1) and a water outlet (2); Step 5: Coat a brazing flux on the brazing connection part of the runner plate (8), and install the cover (7) with an aluminum alloy coating on the runner plate (8) with a channel (80) through the positioning and mounting holes (6) to form a pre-connected liquid cooling plate; Step 6: Place the pre-connected liquid cooling plate in a brazing furnace, control the temperature of the brazing furnace between 610 - 625 °C, and maintain brazing for 8 - 12 minutes in this temperature range, then control the brazing furnace to cool down for 30 minutes to obtain a brazed liquid cooling plate; Step 7: Spray an insulating powder on the surface of the brazed liquid cooling plate, and the thickness of the insulating powder spraying is 200 - 300 microns to obtain a liquid cooling plate with electrical isolation.

8. A method for preparing a liquid cooling plate with a dual liquid cooling structure according to claim 7, characterized in that: In the said Step 2, the conditions of the laser irradiation treatment are: the irradiation wavelength is 1064 nm, the power density is 10^4 - 10^5 W / cm², the scanning speed is 0.5 - 2 m / min, and the single-pass irradiation duration is 50 - 200 ms.

9. A method for manufacturing a liquid cooling plate with a dual liquid cooling structure according to claim 7, characterized in that: In the said Step 3, the spraying amount of the aluminum alloy powder on the surface of the cover blank and the runner plate blank is 8 - 12 g / m².

10. A method for manufacturing a liquid cooling plate with a dual liquid cooling structure according to claim 7, characterized in that: In the said Step 4, the depth of the channel (80) is 4 - 4.5 mm, and the width is 20 - 25 mm.

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