Power battery liquid cooling plate with pinecone biomimetic structure flow channel

Abstract

The application provides a power battery liquid cooling plate with a pinecone bionic structure flow channel and relates to the technical field of power battery thermal management. The power battery liquid cooling plate comprises a liquid cooling plate base body, a three-dimensional spiral hierarchical flow channel network, a central cooling liquid inlet and a cooling liquid outlet arranged at the edge of the liquid cooling plate base body; the three-dimensional spiral hierarchical flow channel network comprises a spiral main channel and hierarchical branch flow channels formed by branching from the spiral main channel; the spiral main channel is in communication with the central cooling liquid inlet; the hierarchical branch flow channels are in communication with the cooling liquid outlet; at least part of the flow channel bottom walls of the hierarchical branch flow channels are provided with scale type turbulence structures; and a self-adapting valve plate made of a shape memory alloy is arranged in the central cooling liquid inlet. The bionic prototype is the natural heat dissipation structure of a pinecone, the heat dissipation efficiency and temperature uniformity are improved, the variable working condition self-adapting capability is enhanced, and the system energy consumption is reduced.

Description

Technical Field

[0001] This invention relates to the field of power battery thermal management technology, specifically to a power battery liquid cooling plate with a pinecone-inspired flow channel structure. Background Technology

[0002] With the rapid development of the new energy vehicle industry, the power density and energy density of power batteries are constantly increasing. During operation, these batteries generate a large amount of heat. If this heat cannot be dissipated in a timely and even manner, it can lead to excessively high battery temperatures and uneven temperature distribution, thereby affecting the battery's cycle life, charge / discharge performance, and safety, and even causing thermal runaway accidents. Therefore, an efficient and stable power battery thermal management system is crucial to ensuring the safe and reliable operation of power batteries.

[0003] As a core component of the thermal management system of a power battery, the flow channel structure design of the liquid cooling plate directly determines its heat dissipation efficiency and temperature uniformity. Currently, the flow channel structures of existing power battery liquid cooling plates mostly adopt traditional structures such as straight channels, serpentine channels, and parallel channels. These structures have the following drawbacks: First, the flow channel topology does not match the thermal distribution characteristics of the power battery, resulting in concentrated heat in the central area but low heat dissipation efficiency, while the edge area experiences excessive heat dissipation, leading to uneven battery temperature distribution. Second, the fluid flow pattern within the flow channel is mostly laminar, with a thick boundary layer, low convective heat transfer coefficient, and limited heat dissipation efficiency. Third, the fixed flow channel structure cannot adaptively adjust to the thermal demands of different battery operating conditions (such as low-temperature start-up, high-temperature discharge, and normal cruising), resulting in high energy consumption. Fourth, the flow channel resistance is relatively large, requiring additional power to drive the coolant circulation, increasing system energy consumption.

[0004] In recent years, topology-optimized flow channels such as leaf vein, blood vessel, and spider web have emerged, improving heat transfer performance by enhancing the uniformity of flow distribution. However, these structures still belong to static topology optimization, and the flow channel geometry parameters are fixed after the design is completed. They lack the ability to adapt to operating conditions and cannot cope with dynamically changing heat generation characteristics. Summary of the Invention

[0005] The present invention aims to solve at least one of the problems mentioned in the background art above, and provides a power battery liquid cooling plate with a pine cone biomimetic flow channel, which uses the natural heat dissipation structure of the pine cone as a biomimetic prototype to improve heat dissipation efficiency and temperature uniformity, enhance the adaptive capability under changing operating conditions, and reduce system energy consumption.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A power battery liquid cooling plate with a pinecone-inspired flow channel structure includes a liquid cooling plate substrate. The liquid cooling plate substrate has a three-dimensional spiral graded flow channel network, a central coolant inlet, and a coolant outlet located at the edge of the liquid cooling plate substrate. The three-dimensional spiral graded flow channel network includes a spiral main channel and graded branch channels branching from the spiral main channel. The spiral main channel is connected to the central coolant inlet, and the graded branch channels are connected to the coolant outlet. At least a portion of the bottom wall of the graded branch channels has a scale-like turbulence structure. An adaptive valve plate made of shape memory alloy is provided in the central coolant inlet.

[0008] Furthermore, the graded branch channels extend in stages from the end of the spiral main channel away from the central coolant inlet, and the included angle between two adjacent graded branch channels is 30°-45°.

[0009] Furthermore, the width of the graded branch channels gradually varies from 3.5mm to 2.5mm from the side closest to the spiral main channel toward the edge of the liquid cooling plate substrate.

[0010] Furthermore, the scale-like turbulence structure imitates the shape of pine cone scales and adopts an isosceles trapezoidal protrusion structure. The bottom width of the scale-like turbulence structure is 3mm-4mm and the height is 1.5mm-2mm. The scale-like turbulence structures are staggered along the bottom wall of the corresponding flow channel, and the distance between two adjacent scale-like turbulence structures is 5mm-8mm.

[0011] Furthermore, the thickness of the adaptive valve plate is 0.3mm-0.5mm, one end of the adaptive valve plate is fixed to the side wall of the flow channel of the central coolant inlet, and an inlet for coolant to pass through is formed between the adaptive valve plate and the flow channel wall of the central coolant inlet; when the coolant temperature is greater than a preset temperature value, the adaptive valve plate deforms in a first direction to increase the cross-sectional area of ​​the inlet; when the coolant temperature is lower than the preset temperature value, the adaptive valve plate returns to its original shape to decrease the cross-sectional area of ​​the inlet.

[0012] Furthermore, the liquid cooling plate substrate has a rectangular structure with dimensions of 200mm × 150mm × 6mm; the diameter of the central coolant inlet is Φ8mm, and the diameter of the coolant outlet is Φ5mm.

[0013] Furthermore, the flow channel depth of both the spiral main channel and the graded branch channels is 2.5mm-3mm.

[0014] Furthermore, the initial width of the spiral main channel is 6mm-8mm, and gradually decreases to 4mm-5mm along the direction away from the central coolant inlet towards the edge of the liquid cooling plate substrate.

[0015] By adopting the above technical solution, the present invention has the following beneficial effects:

[0016] (1) The above-mentioned power battery liquid cooling plate with pine cone biomimetic structure flow channel takes the natural heat dissipation structure of pine cone as the biomimetic prototype, and systematically transforms its spiral stacked arrangement, hierarchical pore network and adaptive opening and closing characteristics into the liquid cooling plate flow channel design. It realizes the precise matching between the biomimetic structure and the thermal management requirements of the power battery, solves the technical problem of mismatch between the existing flow channel and the battery thermal distribution, and significantly improves the uniformity of battery temperature distribution.

[0017] (2) The above-mentioned power battery liquid cooling plate with pine cone bionic structure flow channel expands the heat exchange area of ​​the flow channel by setting a three-dimensional spiral graded flow channel network, realizes the uniform distribution of coolant, and avoids local heat dissipation dead corners; the scale-type turbulence structure can enhance fluid turbulence, destroy the boundary layer, and improve the convective heat transfer coefficient. Compared with the traditional straight channel flow channel, the heat dissipation efficiency is improved by 20%-30%.

[0018] (3) The above-mentioned power battery liquid cooling plate with pine cone bionic structure flow channel adopts the adaptive flow channel wall made of the same shape memory alloy, which can automatically adjust the flow channel opening according to the battery working temperature, realize adaptive thermal management under different working conditions, enhance heat dissipation at high temperature and reduce energy consumption at low temperature. Compared with the fixed flow channel structure, the system energy consumption is reduced by 15%-25%, which improves the driving range of the power battery.

[0019] (4) The above-mentioned power battery liquid cooling plate with pine cone biomimetic flow channel has a spiral main channel and graded branch channel with a gradually changing cross section structure that optimizes the fluid pressure drop distribution, reduces the flow channel resistance, reduces the power consumption required for coolant circulation, and adapts to the center-edge thermal gradient requirements, further improving the heat dissipation uniformity. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the pine cone structure.

[0021] Figure 2 This is a schematic diagram of a power battery liquid cooling plate with a pine cone biomimetic flow channel, according to a preferred embodiment of the present invention.

[0022] Figure 3 for Figure 2 The diagram shows the structure of the liquid cooling plate for the power battery with a pine cone-inspired flow channel at the scale-type turbulence structure.

[0023] Explanation of main component symbols

[0024] 1. Liquid cooling plate substrate; 2. Central coolant inlet; 3. Three-dimensional spiral main channel; 4. Graded branch channels; 5. Scale-type turbulence structure; 6. Adaptive valve plate; 8. Coolant outlet; 10. Pinecone; 11. Scales. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] It should be noted that when a component is described as "fixed to" another component, it can be directly on the other component or may have a component in between. When a component is considered "connected to" another component, it can be directly connected to the other component or may have a component in between. When a component is considered "set on" another component, it can be directly set on the other component or may have a component in between. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0028] Please also see Figures 1 to 3 A preferred embodiment of the present invention provides a liquid cooling plate for a power battery with a pine cone-inspired flow channel structure, wherein the flow channel on the liquid cooling plate is designed based on the natural heat dissipation structure of a pine cone. Figure 1 As shown, in nature, the pine cone 10 has developed a unique natural heat dissipation structure through long-term natural selection: its scales 11 are arranged in a spiral overlapping pattern, forming a natural hierarchical pore network that enables efficient heat conduction and fluid flow; the scales 11 have adaptive opening and closing characteristics, which can adjust the opening and closing degree according to changes in ambient temperature, achieving adaptive heat regulation; at the same time, the center-edge structure of the pine cone forms a natural thermal gradient, which can guide heat to be conducted directionally from the center to the edge, achieving uniform heat dissipation. This embodiment of the invention uses the above-mentioned natural structural features of the pine cone as biomimetic inspiration for the design of the liquid cooling plate flow channel of a power battery.

[0029] Specifically, the power battery liquid cooling plate with a pinecone-inspired flow channel structure includes a liquid cooling plate base 1, on which a central coolant inlet 2 and coolant outlets 8 are located at the edges. In this embodiment, the liquid cooling plate base 1 is made of aluminum alloy and has a rectangular structure with dimensions of 200mm × 150mm × 6mm and an outer contour radius of R5mm to ensure compatibility with conventional power battery modules.

[0030] In this embodiment, the central coolant inlet 2 has a diameter of Φ8mm, serving as a centralized coolant inlet. In this embodiment, the coolant outlet 8 has a diameter of Φ5mm, achieving a flow channel layout of central supply and edge discharge, matching the center-edge heat conduction path of the pinecone. It is understood that the number of coolant outlets 8 can also be set to other numbers as needed.

[0031] A three-dimensional spiral graded flow channel network is provided on the liquid cooling plate substrate 1 as the liquid cooling plate flow channel. The three-dimensional spiral graded flow channel network includes a spiral main channel 3 and graded branch channels 4 branching from the spiral main channel 3. One end of the spiral main channel 3 is connected to the central coolant inlet 2, and the graded branch channels 4 are connected to the coolant outlet 8. At least a portion of the bottom wall of the graded branch channels 4 is provided with a scale-like turbulence structure 5. An adaptive valve plate 6 made of shape memory alloy is provided in the central coolant inlet 2.

[0032] In this embodiment, the three-dimensional spiral graded flow channel network replicates the spiral shingled arrangement and graded pore network characteristics of a pine cone. The three-dimensional spiral graded flow channel network is a multi-level three-dimensional structure, with the flow channel depth of both the spiral main channel 3 and the graded branch channels 4 being 2.5mm-3mm. The spiral main channel 3 adopts a gradually changing cross-sectional structure; specifically, the initial width of the spiral main channel 3 near the central coolant inlet 2 is 6mm-8mm, gradually decreasing to 4mm-5mm outwards along the direction away from the central coolant inlet 2. The spiral main channel 3 mimics the spiral shingled arrangement characteristics of a pine cone, achieving three-dimensional coverage of the flow channel.

[0033] The graded branch channels 4 extend in stages from the end of the spiral main channel 3 away from the central coolant inlet 2, with the included angle between adjacent graded branch channels 4 being 30°-45°. The spiral main channel 3 adopts a gradually changing cross-sectional structure. In this embodiment, the width of the graded branch channels 4 gradually changes from 3.5mm to 2.5mm from the side near the spiral main channel 3 towards the edge of the liquid-cooled plate substrate 1. That is, the width of the graded branch channels 4 gradually changes from 3.5mm near the spiral main channel 3 to 2.5mm towards the edge of the liquid-cooled plate substrate 1. The graded branch channels 4 mimic the graded pore network of a pine cone, ensuring that the coolant can be evenly distributed throughout the liquid-cooled plate area and avoiding insufficient local flow.

[0034] The scale-like turbulence structure 5 mimics the shape of pine cone scales, employing an isosceles trapezoidal protrusion structure. The base width of the scale-like turbulence structure 5 is 3mm-4mm, and its height is 1.5mm-2mm. The scale-like turbulence structures 5 are arranged alternately along the corresponding flow channels, with a spacing of 5mm-8mm between adjacent scale-like turbulence structures 5. By mimicking the shape of pine cone scales, the scale-like turbulence structure 5 enhances the turbulence of the fluid within the flow channel, disrupts the fluid boundary layer, and improves convective heat transfer efficiency.

[0035] The adaptive valve plate 6 is made of Ni-Ti shape memory alloy with a thickness of 0.3mm-0.5mm. One end of the adaptive valve plate 6 is fixed to the side wall of the flow channel of the central coolant inlet 2, forming an inlet for coolant to pass through between the adaptive valve plate 6 and the flow channel wall of the central coolant inlet 2. When the coolant temperature is higher than a preset temperature value, such as ≥50℃, the adaptive valve plate 6 deforms in a first direction to increase the cross-sectional area of ​​the inlet; when the coolant temperature is lower than the preset temperature value, the adaptive valve plate 6 returns to its original shape to reduce the flow channel cross-sectional area, thus achieving dynamic matching between heat load and heat dissipation capacity. The adaptive valve plate 6 can automatically adjust the flow channel opening according to the coolant temperature in the flow channel. Specifically, in one embodiment, when the coolant temperature is higher than 60°C and the battery is in a high-temperature discharge state, the shape memory alloy deforms, and the flow channel opening of the inlet increases by 15%, thereby increasing the coolant flow rate and enhancing heat dissipation. When the coolant temperature is low, such as when the temperature is lower than 10°C and the battery is in a low-temperature start-up state, the adaptive valve plate 6 restores its deformation, thereby reducing the flow channel opening of the inlet and reducing system energy consumption.

[0036] The liquid cooling plate flow channel processing technology in this embodiment is as follows: The flow channel of the liquid cooling plate substrate 1 is processed by CNC milling. Then, the adaptive valve plate 6 is fixed to the side wall of the flow channel by laser welding. Finally, the entire flow channel is ground and polished to ensure that the inner wall of the flow channel is smooth and to reduce fluid resistance. After processing, sealing and heat dissipation performance tests are performed to ensure that the product meets the design requirements.

[0037] The aforementioned power battery liquid cooling plate with a pine cone biomimetic flow channel uses the natural heat dissipation structure of a pine cone as a biomimetic prototype. Its spiral stacked arrangement, hierarchical pore network, and adaptive opening and closing characteristics are systematically transformed into the liquid cooling plate flow channel design. This achieves a precise match between the biomimetic structure and the thermal management requirements of the power battery, solves the technical problem of mismatch between the existing flow channel and the battery thermal distribution, and significantly improves the uniformity of battery temperature distribution.

[0038] The aforementioned power battery liquid cooling plate with a pine cone-inspired flow channel expands the heat exchange area of ​​the flow channel by setting a three-dimensional spiral graded flow channel network, achieving uniform distribution of coolant and avoiding local heat dissipation dead zones; the scale-like turbulence structure can enhance fluid disturbance, destroy the boundary layer, and improve the convective heat transfer coefficient, improving heat dissipation efficiency by 20%-30% compared with traditional straight channel flow channels.

[0039] The aforementioned power battery liquid cooling plate with a pine cone-inspired flow channel uses an adaptive valve plate 6 made of shape memory alloy, which can automatically adjust the flow channel opening according to the battery's operating temperature to achieve adaptive thermal management under varying operating conditions. It enhances heat dissipation at high temperatures and reduces energy consumption at low temperatures. Compared with a fixed flow channel structure, the system energy consumption is reduced by 15%-25%, improving the power battery's range.

[0040] The aforementioned power battery liquid cooling plate with a pine cone biomimetic flow channel has a gradually changing cross-section structure of spiral main channel 3 and graded branch channels 4, which optimizes the fluid pressure drop distribution, reduces flow channel resistance, reduces the power consumption required for coolant circulation, and adapts to the center-edge thermal gradient requirements, further improving heat dissipation uniformity.

[0041] The above description is a detailed description of the preferred embodiments of the present invention. However, the embodiments are not intended to limit the scope of the patent application of the present invention. All equivalent changes or modifications made under the technical spirit of the present invention should fall within the patent scope covered by the present invention.

Claims

1. A liquid cooling plate for a power battery with a pinecone-inspired flow channel, characterized in that, The system includes a liquid cooling plate substrate (1), on which a three-dimensional spiral graded flow channel network, a central coolant inlet (2), and a coolant outlet (8) located at the edge of the liquid cooling plate substrate (1) are provided; the three-dimensional spiral graded flow channel network includes a spiral main channel (3) and graded branch channels (4) formed by branching from the spiral main channel (3), the spiral main channel (3) is connected to the central coolant inlet (2), and the graded branch channels (4) are connected to the coolant outlet (8); at least a portion of the flow channel bottom wall of the graded branch channels (4) is provided with a scale-like turbulence structure (5); the central coolant inlet (2) is provided with an adaptive valve plate (6) made of shape memory alloy.

2. The power battery liquid cooling plate with a pinecone-bionic structure flow channel according to claim 1, characterized in that, The graded branch channels (4) extend from the end of the spiral main channel (3) away from the central coolant inlet (2) in stages, and the included angle between two adjacent graded branch channels (4) is 30°-45°.

3. The power battery liquid cooling plate with a pinecone-bionic structure flow channel according to claim 1, characterized in that, The width of the graded branch channel (4) is gradually distributed from the side near the spiral main channel (3) to the edge of the liquid cooling plate substrate (1) in a range of 3.5mm-2.5mm.

4. The liquid cooling plate for power battery with pinecone bionic structure flow channel according to claim 1, characterized in that, The scale-like turbulence structure (5) imitates the shape of pine cone scales and adopts an isosceles trapezoidal protrusion structure. The scale-like turbulence structure (5) has a bottom width of 3mm-4mm and a height of 1.5mm-2mm. The scale-like turbulence structures (5) are staggered along the bottom wall of the corresponding flow channel, and the distance between two adjacent scale-like turbulence structures (5) is 5mm-8mm.

5. The liquid cooling plate for power battery with pine-bionic structure flow channel according to claim 1, characterized in that, The thickness of the adaptive valve plate (6) is 0.3mm-0.5mm. One end of the adaptive valve plate (6) is fixed to the flow channel side wall of the central coolant inlet (2). An inlet for coolant to pass through is formed between the adaptive valve plate (6) and the flow channel wall of the central coolant inlet (2). When the coolant temperature is greater than a preset temperature value, the adaptive valve plate (6) deforms in a first direction to increase the cross-sectional area of ​​the inlet. When the coolant temperature is lower than the preset temperature value, the adaptive valve plate (6) restores its deformation to reduce the cross-sectional area of ​​the inlet.

6. The liquid cooling plate for power battery with pine-bionic structure flow channel according to claim 1, characterized in that, The liquid cooling plate substrate (1) is a rectangular structure with dimensions of 200mm×150mm×6mm; the diameter of the central coolant inlet (2) is Φ8mm, and the diameter of the coolant outlet (8) is Φ5mm.

7. The power battery liquid cooling plate with a pinecone-inspired flow channel according to claim 1, characterized in that, The channel depth of both the spiral main channel (3) and the graded branch channels (4) is 2.5mm-3mm.

8. The liquid cooling plate for power battery with pine-bionic structure flow channel according to claim 1, characterized in that, The spiral main channel (3) has an initial width of 6mm-8mm, which gradually decreases to 4mm-5mm along the direction away from the central coolant inlet (2) towards the edge of the liquid cooling plate substrate (1).

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