Self-adaptive heat management structure based on bionic topology and preparation method and application thereof

Abstract

The invention discloses a self-adaptive heat management structure based on bionic topology and a preparation method and application thereof, and relates to the technical field of battery heat management materials and structures. The structure comprises a nanofiber reinforced phase change material filled in pores of a porous framework, the porous framework has a topological hexagonal honeycomb structure, and the size of a honeycomb unit in the topological hexagonal honeycomb structure is differentially set according to the temperature of a battery surface area covered by the honeycomb unit; and the size of the honeycomb unit corresponding to a high-temperature area of the battery surface is larger than that of the honeycomb unit corresponding to a low-temperature area. The preparation method comprises the following steps: optimally designing a skeleton three-dimensional model; manufacturing a framework by using light alloy powder through a selective laser melting technology; preparing a nanofiber reinforced phase change material; compounding is completed through a vacuum pressure impregnation method. The structure prepared by the invention has excellent structural strength, efficient heat spreading inhibition capability and intrinsic safety, and is especially suitable for battery thermal runaway protection of an unmanned system.

Description

Technical Field

[0001] This invention belongs to the field of battery thermal management materials and structures, specifically relating to an adaptive thermal management structure based on biomimetic topology, its preparation method, and its application. Background Technology

[0002] Modern unmanned systems rely on high-energy-density lithium-ion batteries. However, complex service environments and high-rate charging and discharging conditions can easily induce thermal runaway in batteries, which can cause temperatures to spike and explode within tens of seconds. This is a core hidden danger threatening the survival of unmanned systems.

[0003] Currently, battery thermal management systems are mainly divided into two categories: active and passive. Active thermal management systems typically use liquid cooling or air cooling to continuously remove heat through an external circulation system; while passive thermal management systems mainly rely on phase change materials to absorb heat, requiring no external energy input. In passive thermal management systems, phase change materials are widely used due to their high latent heat and temperature stability, but the poor thermal conductivity of pure phase change materials limits their thermal management efficiency.

[0004] To improve the thermal conductivity of phase change materials (PCMs), researchers have developed various composite PCM structures. CN205062152U discloses a metal fiber porous skeleton composite PCM heat sink, comprising a metal fiber porous skeleton, a PCM, a heat sink substrate, and heat dissipation fins. The metal fiber porous skeleton fills the cavity of the heat sink substrate, with a porosity of 75%–98%. The PCM is filled into the pores within the metal fiber porous skeleton via vacuum heating infusion. CN105296898B further details the manufacturing method of this metal fiber porous skeleton composite PCM heat sink, demonstrating that embedding the metal fiber porous skeleton within the PCM effectively enhances the thermal conductivity of the PCM inside the heat sink.

[0005] Regarding the design of the frame structure, CN108102615A proposes a novel shaped phase change thermal control device based on a honeycomb structure. This device combines shaped phase change material with a honeycomb panel and attaches an aluminum skin to the outer surface, which significantly improves the longitudinal thermal conductivity, thereby achieving more effective temperature control. CN115551304A discloses a high-efficiency phase change cooling thermal management system for electrical components. This system includes a shell, a metal frame, and a phase change material. The metal frame is a curved thin-walled structure, uniformly arranged in the inner cavity of the shell, dividing the inner cavity into multiple partitions. The phase change material fills the partitions enclosed by the metal frame.

[0006] Regarding material selection, CN118699404A introduces a bi-interpenetrating composite material with a biomimetic structure and its preparation method. The method uses 3D printing equipment to prepare a reinforcing phase skeleton with a biomimetic structure, and obtains a composite material with strong interfacial bonding and good mechanical and thermal conductivity through surface treatment and matrix phase melting treatment.

[0007] However, existing battery thermal management solutions still have the following technical problems: First, active liquid cooling solutions rely on external circulation systems, which are at risk of failure under the severe impact of thermal runaway, and the structure does not have the ability to contain the impact of battery explosion at high temperatures; Second, local liquid cooling / air cooling solutions have incomplete thermal management paths, making it difficult to achieve rapid and comprehensive thermal shock dissipation in the face of instantaneous omnidirectional thermal runaway, easily forming local hot spots that lead to heat spread; Third, existing composite phase change material blocks, as the core structure, will melt and flow away at the high temperatures of thermal runaway, leading to a sharp decrease in structural strength, softening and collapse, and potentially causing secondary risks such as leakage and short circuits; Finally, existing solutions are mostly based on experience in material and interface design, resulting in weak interface bonding, high thermal resistance, and affecting overall thermal management efficiency. Summary of the Invention

[0008] In order to overcome the shortcomings of the prior art, the present invention aims to provide an adaptive thermal management structure based on biomimetic topology, its preparation method and application, so as to solve the technical problem that existing battery thermal management technologies cannot simultaneously achieve efficient thermal propagation suppression and high-strength physical containment under extreme thermal runaway conditions.

[0009] To achieve the above objectives, the present invention employs the following technical solution: In a first aspect, the present invention provides an adaptive thermal management structure based on biomimetic topology, comprising an integrally formed lightweight alloy porous skeleton and a nanofiber-reinforced phase change material filling the pores of the porous skeleton; the porous skeleton has a topological hexagonal honeycomb structure, and the size of the honeycomb cells in the topological hexagonal honeycomb structure is differentiated according to the temperature of the battery surface region it covers: the size of the honeycomb cells in the high-temperature region of the corresponding battery surface is larger than the size of the honeycomb cells in the low-temperature region.

[0010] A further improvement of the present invention is that the lightweight alloy is an AlSiMgCuLi alloy, and by mass percentage, the elemental composition of the alloy includes 16.0%-19.5% Al, 17.5%-20.0% Si, 14.5%-17.0% Mg, 4.0%-5.5% Li, and the balance is Cu.

[0011] A further improvement of the present invention is that the compressive strength of the porous skeleton is 450-600 MPa.

[0012] A further improvement of this invention is that, in the topological hexagonal honeycomb structure, the honeycomb cells corresponding to the high-temperature region, medium-temperature region, and low-temperature region of the battery surface have a side length ratio of (8-5):(5-3):1.

[0013] A further improvement of the present invention is that the wall thickness of the unit cell of the topological hexagonal honeycomb structure is 1.5-2.5 mm.

[0014] A further improvement of the present invention is that the nanofiber-reinforced phase change material comprises a matrix phase change material and a nanofiber-reinforced phase dispersed therein.

[0015] A further improvement of the present invention is that the matrix phase change material is any one of paraffin, tetradecane, hexadecane, n-octadecane and lauric acid; the nanofiber reinforcing phase is any one of carbon fiber, carbon nanotube, graphene nanosheet, boron nitride nanofiber and alumina nanofiber, and its addition amount is 1%-5% of the mass of the matrix phase change material.

[0016] Secondly, the present invention also provides a method for fabricating an adaptive thermal management structure based on biomimetic topology, comprising the following steps: S1: Topology skeleton design and optimization: Based on the temperature field distribution on the battery surface, design and optimize the skeleton three-dimensional model with differentiated cell sizes; S2: Structure preparation: Using lightweight alloy powder, based on the three-dimensional model obtained in S1, the integrally formed porous skeleton is manufactured by selective laser melting technology; S3: Composite material preparation: Preparation of the nanofiber-reinforced phase change material; S4: Vacuum impregnation composite: The nanofiber-reinforced phase change material prepared in S3 is filled into the pores of the porous skeleton prepared in S2 by vacuum pressure impregnation method to obtain the biomimetic topology-based adaptive thermal management structure.

[0017] A further improvement of the present invention is that, in S2, the process parameters for selective laser melting are: laser power of 300-380W, scanning speed of 1200-2000mm / s, scanning spacing of 0.05-0.12mm, and layer thickness of 0.02-0.04mm.

[0018] Thirdly, the present invention also provides an application of an adaptive thermal management structure based on biomimetic topology in battery thermal runaway protection.

[0019] Compared with the prior art, the present invention has the following beneficial effects: This invention provides an adaptive thermal management structure based on biomimetic topology, integrating thermal management and structural load-bearing functions to enhance intrinsically safe high-temperature physical containment capabilities. The invention utilizes a one-piece molded lightweight alloy porous framework, which is itself a high-strength structural component with a melting point and high-temperature strength far exceeding those of phase change materials and existing composite material blocks. In the event of extreme thermal runaway, this framework acts as a robust load-bearing structure, maintaining structural integrity and effectively containing the heat flow impact generated during thermal runaway. This solves the fundamental flaw of existing technologies, where structural collapse is caused by material melting and loss, providing the most fundamental physical barrier for battery safety.

[0020] Secondly, the hexagonal honeycomb structure in this design is optimized using algorithms to minimize thermal resistance and maximize structural stiffness, forming an efficient and orderly heat transfer channel. When a battery experiences a massive thermal shock during thermal runaway, this structure can rapidly and directionally conduct and diffuse heat, significantly slowing down the temperature rise and effectively preventing the chain-like spread of heat between batteries, thus buying valuable time for a safe system response.

[0021] Furthermore, this invention constructs a stable and reliable composite material system by reinforcing phase change materials with nanofibers. By introducing nanofiber-reinforcing phases, a three-dimensional network structure is formed in the phase change material matrix, significantly improving its solid-state strength and effectively preventing molten leakage. This fundamentally eliminates the industry problem of easy leakage of traditional phase change materials at high temperatures, avoids secondary risks such as short circuits that may be caused by this, and ensures the long-term stability of the composite material under extreme working conditions.

[0022] Finally, by configuring large-sized honeycomb cells in the high-temperature region of the battery, the amount of phase change material and its heat capacity were significantly increased, enhancing the heat absorption and buffering capacity and effectively delaying the temperature rise in the early stages of thermal runaway. Simultaneously, configuring small-sized honeycomb cells in the low-temperature region increased the material packing density and structural stiffness, strengthening the mechanical support and physical containment of the battery module. This gradient size design enables the structure to autonomously adjust its thermal management strategy according to the battery's thermal state, achieving a technological leap from homogeneous passive protection to on-demand active heat dissipation. The optimized heat flow path prevents localized heat accumulation during localized thermal runaway, and the synergistic effect effectively blocks the chain propagation of thermal runaway between batteries, buying valuable time for system safety response and significantly improving the system's adaptability and reliability under complex operating conditions.

[0023] This invention also provides a method for fabricating an adaptive thermal management structure based on biomimetic topology. First, a three-dimensional skeleton model with differentiated honeycomb cell sizes is designed and optimized according to the temperature field distribution on the battery surface. Then, selective laser melting (SLM) technology is used. This method overcomes the limitations of traditional casting or sintering processes, enabling the optimized porous skeleton with a complex internal gradient structure to be integrally molded in one step. This fundamentally ensures that the product has high precision, high density, and consistent mechanical properties, laying the foundation for reliable structural support. Furthermore, a vacuum pressure impregnation method is used. By eliminating pore gas in a vacuum environment and using pressure to drive the process, the nanofiber-reinforced phase change material is ensured to fully and completely fill every micropore of the skeleton, achieving a tight microscopic bond between the two phases. This effectively avoids the formation of defects such as air gaps, significantly reducing interfacial thermal resistance and ensuring efficient heat conduction within the composite. Attached Figure Description

[0024] The accompanying drawings described herein are for illustrative purposes only and are not intended to limit the scope of the invention in any way. Furthermore, the shapes and proportions of the components in the drawings are merely illustrative to aid in understanding the invention and do not specifically limit the shapes and proportions of the components of the invention.

[0025] Figure 1 The image shows the microstructure of the prepared biomimetic honeycomb composite structure. Figure 2 This is a flowchart illustrating the fabrication process of the biomimetic topological adaptive thermal management structure of the present invention. Figure 3 This is the simulation model of Embodiment 2 of the present invention; Figure 4 This is the paraffin melting fraction curve of Example 2 of the present invention; Figure 5 This is a graph showing the change in the Nu number in Embodiment 2 of the present invention. Detailed Implementation

[0026] To enable those skilled in the art to understand the features and effects of the present invention, the terms and expressions used in the specification and claims are explained and defined in general below. Unless otherwise specified, all technical and scientific terms used herein have the ordinary meaning understood by those skilled in the art regarding the present invention, and in case of conflict, the definitions in this specification shall prevail.

[0027] The theories or mechanisms described and disclosed herein, whether right or wrong, should not in any way limit the scope of the invention, that is, the contents of the invention can be implemented without being limited by any particular theory or mechanism.

[0028] In this document, all features defined by numerical ranges or percentage ranges, such as numerical values, quantities, contents, and concentrations, are for the sake of brevity and convenience only. Accordingly, descriptions of numerical ranges or percentage ranges should be considered as covering and specifically disclosing all possible sub-ranges and individual numerical values ​​(including integers and fractions) within those ranges.

[0029] For the sake of brevity, not all possible combinations of the technical features in each implementation scheme or embodiment are described herein. Therefore, as long as there is no contradiction in the combination of these technical features, the technical features in each implementation scheme or embodiment can be combined arbitrarily, and all possible combinations should be considered within the scope of this specification.

[0030] This invention provides an adaptive thermal management structure based on biomimetic topology, comprising a one-piece molded lightweight alloy porous framework and a nanofiber-reinforced phase change material filling the pores of the porous framework; the porous framework has a topological hexagonal honeycomb structure designed based on biomimetic principles, such as... Figure 1 As shown, the size of the cell in the hexagonal honeycomb structure is set differently according to the temperature of the battery surface area it covers: the size of the cell in the high temperature area of ​​the corresponding battery surface is larger than the size of the cell in the low temperature area.

[0031] The porous framework features a topological hexagonal honeycomb structure. The biomimetic honeycomb topological optimization design in this structure draws profound inspiration from two aspects of nature. First, it originates from the stable hexagonal configuration of the honeycomb itself, achieving maximum structural efficiency and stability with minimal material. Second, it is influenced by plant ecological adaptability, particularly the manifestation of Bergmann's Law in leaf shape—in hot and humid regions, plant leaves are typically large to facilitate heat dissipation; while in cold regions, leaves are smaller to reduce heat loss.

[0032] Based on this dual biomimetic principle, this invention optimizes the honeycomb size topology to address the uneven temperature distribution on the battery surface. Specifically, in the higher-temperature regions of the battery module, relatively larger honeycomb cells are designed to enhance their heat capacity and heat storage capabilities, simulating the enhanced heat dissipation mechanism of the "broad-leaved southern leaf"; while in the lower-temperature regions, smaller honeycomb cells are configured to improve structural compactness and mechanical support, simulating the heat insulation and robustness characteristics of the "small-leaved northern leaf". This gradient honeycomb design based on the actual thermal field distribution achieves a globally optimal match between thermal management efficiency and structural load-bearing efficiency. In the topological hexagonal honeycomb structure, the side length ratio of the honeycomb cells corresponding to the high-temperature, medium-temperature, and low-temperature regions of the battery surface is (8-5):(5-3):1.

[0033] As a preferred option, the lightweight alloy is an AlSiMgCuLi alloy, whose elemental composition, by mass percentage, includes 16.0%-19.5% Al, 17.5%-20.0% Si, 14.5%-17.0% Mg, 4.0%-5.5% Li, with the balance being Cu. This porous framework has a topological hexagonal honeycomb structure, with a unit wall thickness of 1.5-2.5 mm, ensuring structural stability while providing sufficient space to accommodate the phase change material.

[0034] As a preferred option, the porous skeleton has a compressive strength of 450-600MPa, which allows the structure to maintain excellent mechanical properties while being lightweight.

[0035] As a preferred embodiment, the nanofiber-reinforced phase change material comprises a matrix phase change material and a nanofiber reinforcing phase dispersed therein; the matrix phase change material is not limited to paraffin wax, but may also be selected from any of the following materials: tetradecane, hexadecane, n-octadecane, and lauric acid. The nanofiber reinforcing phase is not limited to carbon fiber, but may also be selected from any of the following materials: carbon nanotubes, graphene nanosheets, boron nitride nanofibers, and alumina nanofibers. The amount of the nanofiber reinforcing phase added is 1%-5% of the mass of the matrix phase change material; the surface of the carbon fiber reinforcing phase is modified with a silane coupling agent.

[0036] It should be noted that in the field of composite materials, the interfacial compatibility between the reinforcing phase and the matrix phase is crucial in determining the final performance of the composite material. Untreated carbon fiber surfaces are chemically inert and have a significantly different surface energy from most polymer matrices, resulting in poor wettability and weak interfacial bonding. Therefore, this invention employs a silane coupling agent to treat the surface of the nanofiber reinforcing phase. Its mechanism of action is as follows: the functional groups at one end of the silane coupling agent molecule can chemically react with hydroxyl groups and other groups on the surface of the nanofiber reinforcing phase to form strong covalent bonds; while the long organic chains at the other end have good compatibility with the matrix phase change material, and may even entangle.

[0037] When this biomimetic topology-based adaptive thermal management structure is in operation, as the internal heat source temperature rises, the phase change material filled within the framework begins to absorb heat and undergo a phase change, effectively reducing the heat source temperature. The addition of carbon fibers further improves the thermal conductivity of the phase change material, accelerating the heat transfer process. When the heat source stops working or the temperature drops, the phase change material releases the stored heat, achieving thermal energy recovery and utilization.

[0038] like Figure 2 As shown, the present invention also provides a method for fabricating an adaptive thermal management structure based on biomimetic topology, comprising the following steps: S1: Topology skeleton design and optimization: Based on the temperature field distribution on the battery surface, design and optimize the skeleton three-dimensional model with differentiated cell sizes; S2: Structure preparation: Using lightweight alloy powder, based on the three-dimensional model obtained in S1, the integrally formed porous skeleton is manufactured by selective laser melting technology; S3: Composite material preparation: Preparation of the nanofiber-reinforced phase change material; S4: Vacuum impregnation composite: The nanofiber-reinforced phase change material prepared in S3 is filled into the pores of the porous skeleton prepared in S2 by vacuum pressure impregnation method to obtain the biomimetic topology-based adaptive thermal management structure.

[0039] In step S1, the optimization takes maximizing structural stiffness and minimizing thermal resistance as the dual objective functions, with a compressive strength of 450-600MPa as the constraint condition; the unit side length of the biomimetic hexagonal honeycomb structure is 0.45-0.9mm, and the wall thickness is 1.5-2.5mm.

[0040] In step S2, the lightweight alloy powder is AlSiMgCuLi alloy powder with a particle size distribution of 15-53μm; the process parameters of the selective laser melting (SLM) are: laser power of 300-380W, scanning speed of 1200-2000mm / s, scanning spacing of 0.05-0.12mm, and layer thickness of 0.02-0.04mm.

[0041] In step S3, the preparation process of the nanofiber-reinforced phase change material includes: The matrix phase change material is heated to a completely molten state to obtain a molten matrix phase change material; The nanofiber-reinforced phase was surface-modified with a silane coupling agent to obtain the modified nanofiber-reinforced phase. The modified nanofiber-reinforced phase is added to the molten matrix phase change material at an addition amount of 1%-5%, and treated for 50-70 minutes by a combination of mechanical stirring and ultrasonic vibration to ensure uniform dispersion, thereby obtaining the nanofiber-reinforced phase change material.

[0042] In step S4, the specific process of the vacuum pressure impregnation method includes: Preheat the porous skeleton prepared in step S2 to 60°C; In a vacuum environment, the molten nanofiber-reinforced phase change material prepared in step S3 is impregnated into the pores of a porous framework. The vacuum is evacuated to -0.1 MPa and held for 25-35 minutes, followed by pressure holding for 110-130 minutes to obtain a biomimetic topological adaptive thermal management structure.

[0043] This invention also provides an application of a biomimetic topology-based adaptive thermal management structure in battery thermal runaway protection. This biomimetic topology-based adaptive thermal management structure is installed on the periphery of the battery module or between individual battery cells. When the battery temperature rises abnormally due to overcharging, over-discharging, or internal short circuits, the phase change material in the thermal management structure can rapidly absorb heat, slowing the rate of heat transfer to surrounding batteries and effectively preventing the spread of thermal runaway within the battery pack. In practical applications, the biomimetic topology-based adaptive thermal management structure can be made into a plate or block shape suitable for the shape of the battery module and directly attached to the battery surface.

[0044] Example 1 This embodiment provides a method for fabricating an adaptive thermal management structure based on biomimetic topology, focusing on optimizing lightweight design and basic thermal buffering performance. The method includes the following steps: S1: Topology Skeleton Design and Optimization Based on simulation analysis of the battery surface temperature field, and combined with topology optimization algorithms, a three-dimensional skeleton model with gradient honeycomb dimensions is established. In this model, the side length ratio of the honeycomb cells in the high-temperature, medium-temperature, and low-temperature regions is 5:3:1, which is set as the left limit within the parameter range to achieve lightweight structural design while meeting basic thermal management requirements. The optimization objective is to minimize thermal resistance and maximize structural stiffness under a compressive strength of 450 MPa.

[0045] S2: Structure Preparation AlSiMgCuLi alloy powder was used, with the following composition by mass percentage: Al 16.0%, Si 17.5%, Mg 14.5%, Li 4.0%, and the balance Cu. This composition ratio emphasizes lightweight and low strength within the specified range. The powder particle size was controlled between 15-53 μm, and a monolithic porous framework was fabricated using selective laser melting (SLM). The process parameters were set to their left limits: laser power 300 W, scanning speed 1200 mm / s, scanning spacing 0.05 mm, and layer thickness 0.02 mm. The resulting hexagonal honeycomb structure unit had a wall thickness of 1.5 mm, and the formed framework underwent mechanical testing, showing a compressive strength of 460 MPa.

[0046] S3: Composite Material Preparation Paraffin wax, with a phase change temperature of 45-50℃, was used as the matrix phase change material and heated to complete melting. Carbon fibers with a diameter of 50-200 nm were selected as the reinforcing phase, surface-treated with silane coupling agent KH-550, and added to the molten paraffin wax at 1% of the paraffin wax mass. The mixture was mechanically stirred (500 r / min) and ultrasonically vibrated (40 kHz) for 50 minutes to obtain a uniformly dispersed nanofiber-reinforced phase change material slurry.

[0047] S4: Vacuum pressure impregnation composite After preheating the skeleton to 60°C, it was placed in an impregnation tank, and the aforementioned composite slurry was injected to completely submerge the skeleton. A vacuum was first drawn to -0.1 MPa and maintained for 25 minutes to remove pore gas. Then, nitrogen gas was introduced and a pressure of 0.6 MPa was applied, maintaining the pressure for 110 minutes to ensure the slurry fully fills all pores of the skeleton. After cooling and curing, the surface was cleaned to obtain a lightweight biomimetic topological adaptive thermal management structure.

[0048] Through simulation and experimental verification, under the condition of heat source temperature of 343.15K, the melting fraction of phase change material in the high temperature region reaches 0.5 within 10 minutes, and the thermal spread delay is about 35%, which effectively verifies the synergistic effect of lightweight components and structural gradient design in basic thermal buffering.

[0049] Example 2 This embodiment provides a method for fabricating a biomimetic topology-based adaptive thermal management structure that balances thermal management efficiency and structural strength, including the following steps: S1: Topology Skeleton Design and Optimization Based on the actual temperature distribution on the battery surface, a skeleton model with a cellular cell side length ratio of 6.5:4:1 (high temperature zone: medium temperature zone: low temperature zone) was constructed using response surface methodology and a multi-objective optimization algorithm. This is the median parameter configuration, designed to balance thermal capacity and mechanical support performance. During optimization, the improvement rate of thermal conductivity and the rate of stiffness decay were used as evaluation indicators to ensure the stability of the structure during continuous operation.

[0050] S2: Structure Preparation AlSiMgCuLi alloy powder was selected, with its composition adjusted by mass percentage as follows: Al 17.5%, Si 18.5%, Mg 15.5%, Li 4.5%, and the balance Cu. This ratio emphasizes comprehensive mechanical and thermal conductivity properties. The powder particle size was maintained at 15-53 μm. The skeleton was formed using selective laser melting (SLM) technology, with the following process parameters taken as median values: laser power 340 W, scanning speed 1600 mm / s, scanning spacing 0.085 mm, and layer thickness 0.03 mm. The honeycomb unit wall thickness was set to 2.0 mm, and the minimum compressive strength of the formed skeleton was 480 MPa.

[0051] S3: Composite Material Preparation Using paraffin as the matrix phase change material, a surface-modified carbon fiber nano-reinforcing phase was added at a concentration of 3% of the paraffin mass. The mixture was then subjected to a combination of mechanical stirring and ultrasonic vibration for 60 minutes to prepare a composite slurry with moderate viscosity and uniform distribution of the reinforcing phase.

[0052] S4: Vacuum pressure impregnation composite After the skeleton is preheated to 60°C, it is placed in an impregnation environment, vacuumed to -0.1MPa and maintained for 30 minutes, and then held at 0.6MPa for 120 minutes to achieve full penetration and interfacial bonding of the composite material into the skeleton.

[0053] Through simulation and thermal cycling experiments, it has been demonstrated that, Figures 3 to 5 As shown, the structure maintains a stable interfacial heat flux density and a gradual change in Nu number during thermal shock, completing a smooth phase transition within 15 minutes without significant heat accumulation, demonstrating the innovative advantages of balanced component design and controllable heat conduction mechanism.

[0054] Example 3 This embodiment provides a method for fabricating an adaptive thermal management structure based on a high-performance biomimetic topology for protection against extreme thermal runaway. The specific steps are as follows: S1: Topology Skeleton Design and Optimization To address the extreme thermal runaway conditions of high-energy-density battery modules, a skeleton model with a cell side length ratio of 8:5:1 (high-temperature zone: medium-temperature zone: low-temperature zone) was designed. This is the right limit setting of the parameters, focusing on enhancing the heat capacity and structural impact resistance of the high-temperature region. Transient thermal shock loads were introduced during the optimization process to ensure the integrity of the structure under extreme conditions.

[0055] S2: Structure Preparation AlSiMgCuLi alloy powder was used, with the following composition by mass percentage: Al 19.5%, Si 20.0%, Mg 17.0%, Li 5.5%, and the balance Cu. This composition emphasizes high-temperature strength and creep resistance. The skeleton was formed using selective laser melting (SLM) technology under the following extreme process parameters: laser power 380W, scanning speed 2000mm / s, scanning spacing 0.12mm, and layer thickness 0.04mm. The cell wall thickness was set to 2.5mm, and the minimum compressive strength of the formed skeleton, after testing, reached 500MPa.

[0056] S3: Composite Material Preparation Using paraffin as the matrix, a surface-modified carbon fiber reinforcing phase was added, with the addition amount increased to 5% of the paraffin mass. After mechanical stirring and ultrasonic vibration treatment for 70 minutes, a stable three-dimensional thermally conductive network was constructed, which significantly improved the high-temperature shape retention and leakage resistance of the composite material.

[0057] S4: Vacuum pressure impregnation composite Molten composite slurry is injected into a preheated skeleton under vacuum, vacuum is drawn to -0.1MPa and held for 35 minutes, and then pressure of 0.6MPa is applied and held for 130 minutes to achieve full filling of material and tight bonding with the interface.

[0058] Through extreme working condition simulation and experimental verification, this structure can withstand heat flux densities > 50kW / m³. 2It remains intact under these conditions. The phase change material melts to 0.8% in the high-temperature region within 12 minutes, and the thermal propagation delay time is increased by about 50%, which fully demonstrates the synergistic enhancement effect of high-strength components and adaptive thermal conduction mechanism in extreme protection.

[0059] The above three embodiments, through systematic adjustment of alloy composition, structural parameters and process conditions, fully demonstrate the innovation of this invention in multi-dimensional collaborative design of materials, structure and process, and provide customizable and verifiable solutions for battery thermal safety protection in different application scenarios.

[0060] The above embodiments, through strength test box simulation experiments, demonstrate that under different parameter combinations, the structure can meet the requirement of compressive strength of 450-600 MPa and exhibits good thermal management efficiency. The biomimetic topological adaptive thermal management structure obtained through the above embodiments combines excellent structural strength, efficient thermal management capabilities, and inherent safety, providing a certain guarantee for the safe operation of modern unmanned systems.

[0061] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. An adaptive thermal management structure based on biomimetic topology, characterized in that, It includes a one-piece molded lightweight alloy porous framework and a nanofiber-reinforced phase change material filling the pores of the porous framework; The porous skeleton has a topological hexagonal honeycomb structure, and the size of the honeycomb cells in the topological hexagonal honeycomb structure is set differently according to the temperature of the battery surface area it covers: the size of the honeycomb cells in the high temperature area of ​​the corresponding battery surface is larger than the size of the honeycomb cells in the low temperature area.

2. The adaptive thermal management structure based on biomimetic topology according to claim 1, characterized in that, The lightweight alloy is an AlSiMgCuLi alloy, which, by mass percentage, comprises 16.0%-19.5% Al, 17.5%-20.0% Si, 14.5%-17.0% Mg, 4.0%-5.5% Li, with the balance being Cu.

3. The adaptive thermal management structure based on biomimetic topology according to claim 1, characterized in that, The compressive strength of the porous skeleton is 450-600 MPa.

4. The adaptive thermal management structure based on biomimetic topology according to claim 1, characterized in that, In the aforementioned hexagonal honeycomb structure, the honeycomb cells corresponding to the high-temperature, medium-temperature, and low-temperature regions on the battery surface have a side length ratio of (8-5):(5-3):

1.

5. The adaptive thermal management structure based on biomimetic topology according to claim 1, characterized in that, The unit wall thickness of the topological hexagonal honeycomb structure is 1.5-2.5 mm.

6. The adaptive thermal management structure based on biomimetic topology according to claim 1, characterized in that, The nanofiber-reinforced phase change material comprises a matrix phase change material and a nanofiber-reinforced phase dispersed therein.

7. The adaptive thermal management structure based on biomimetic topology according to claim 1, characterized in that, The matrix phase change material is any one of paraffin, tetradecane, hexadecane, n-octadecane, and lauric acid; the nanofiber reinforcing phase is any one of carbon fiber, carbon nanotube, graphene nanosheet, boron nitride nanofiber, and alumina nanofiber, and its addition amount is 1%-5% of the mass of the matrix phase change material.

8. A method for fabricating an adaptive thermal management structure based on biomimetic topology as described in any one of claims 1 to 7, characterized in that, Includes the following steps: S1: Topology skeleton design and optimization: Based on the temperature field distribution on the battery surface, design and optimize the skeleton three-dimensional model with differentiated honeycomb cell sizes; S2: Structure preparation: Using lightweight alloy powder, based on the three-dimensional model obtained in S1, the integrally formed porous skeleton is manufactured by selective laser melting technology; S3: Composite material preparation: Preparation of the nanofiber-reinforced phase change material; S4: Vacuum impregnation composite: The nanofiber-reinforced phase change material prepared in S3 is filled into the pores of the porous skeleton prepared in S2 by vacuum pressure impregnation method to obtain the biomimetic topology-based adaptive thermal management structure.

9. The method for fabricating an adaptive thermal management structure based on biomimetic topology according to claim 8, characterized in that, In S2, the process parameters for selective laser melting are as follows: laser power of 300-380W, scanning speed of 1200-2000mm / s, scanning spacing of 0.05-0.12mm, and layer thickness of 0.02-0.04mm.

10. The application of an adaptive thermal management structure based on biomimetic topology as described in any one of claims 1 to 7 in battery thermal runaway protection.

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