A new energy battery pack with high safety performance

Abstract

The application discloses a new energy battery pack with high safety performance, which comprises a plurality of battery monomers arranged in sequence and stacked, at least two multifunctional protective pads arranged at intervals between two adjacent battery monomers, and a heat dissipation gap formed between two adjacent multifunctional protective pads; the multifunctional protective pad comprises a heat absorption and dissipation layer and a heat insulation buffer layer arranged on both sides of the heat absorption and dissipation layer; the heat insulation buffer layer is made of ceramicized silica gel foam and comprises a first ceramicized silica gel foam, a second ceramicized silica gel foam and a third ceramicized silica gel foam arranged in sequence from inside to outside, and the density p1 of the first ceramicized silica gel foam, the density p2 of the second ceramicized silica gel foam and the density p3 of the third ceramicized silica gel foam satisfy the relationship: p1>p2>p3. Compared with the prior art, the new energy battery pack provided by the application has the advantages of efficient heat dissipation, excellent heat insulation protection and good buffering performance, so as to guarantee the safety and durability of the battery pack.

Description

Technical Field

[0001] This invention relates to the field of new energy battery technology, specifically to a new energy battery pack with high safety performance. Background Technology

[0002] In the development and use of new energy battery packs, especially in electric vehicles and large-scale energy storage systems, battery safety and efficiency are paramount. Thermal management of battery modules during operation is a key factor affecting battery performance and safety. Traditional battery modules are typically designed with cell energy density and output efficiency in mind, but often have shortcomings in their heat dissipation structure design.

[0003] Because chemical reactions occur during charging and discharging, the heat released by these reactions causes the internal temperature of the battery to rise. Especially under high load or fast charging conditions, battery temperature control becomes a challenge. High temperatures not only reduce battery efficiency but can also cause aging of battery materials, shorten battery life, and even trigger thermal runaway in extreme cases, leading to safety accidents.

[0004] Furthermore, the close arrangement of multiple cells in a battery module exacerbates the heat dissipation problem. Poor heat dissipation of an individual cell not only affects its own performance but also the overall thermal management of the module. Currently, most battery module heat dissipation technologies on the market rely on traditional thermally conductive materials and heat sink designs, but these methods often fail to provide adequate thermal management in high-power output and fast-charging applications.

[0005] To address these issues, existing battery pack technologies fall short in the following aspects:

[0006] 1) Poor thermal insulation performance: When the battery is in thermal runaway, it is difficult to effectively prevent the spread of heat dissipation problems, which can easily lead to excessive temperature difference between cells inside the module, thereby causing fire or explosion.

[0007] 2) Insufficient buffering performance: During operation or charging, the battery may expand due to changes in internal pressure. Existing technology has failed to provide effective mechanical buffering to reduce structural damage or performance degradation caused by expansion.

[0008] 3) Insufficient thermal conductivity and heat dissipation performance: The existing heat dissipation structure fails to effectively conduct the heat generated by the battery cell away quickly, resulting in heat accumulation problems when the battery module is running at high efficiency.

[0009] Given these challenges, it is particularly urgent to develop a new type of battery pack with efficient heat dissipation, excellent thermal insulation protection, and good buffering performance. Summary of the Invention

[0010] The main purpose of this disclosure is to provide a new type of new energy battery pack with efficient heat dissipation, excellent thermal insulation protection and good buffering performance.

[0011] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0012] A new energy battery pack with high safety performance includes multiple battery cells stacked sequentially, with at least two spaced-apart multifunctional protective pads between adjacent battery cells, and a heat dissipation gap formed between adjacent multifunctional protective pads; the multifunctional protective pad includes a heat absorption and heat dissipation layer and a heat insulation buffer layer disposed on both sides of the heat absorption and heat dissipation layer.

[0013] The heat insulation buffer layer is made of ceramicized silicone foam, comprising a first ceramicized silicone foam, a second ceramicized silicone foam, and a third ceramicized silicone foam arranged sequentially from the inside out. The densities ρ1 of the first ceramicized silicone foam, ρ2 of the second ceramicized silicone foam, and ρ3 of the third ceramicized silicone foam satisfy the relationship: ρ1 > ρ2 > ρ3; and the density ρ1 of the first ceramicized silicone foam is 300 kg / m³. 3 ~400kg / m 3 The density ρ2 of the second ceramicized silicone foam is 200 kg / m³. 3 ~300kg / m 3 The density ρ3 of the third ceramicized silicone foam is 100 kg / m³. 3 ~200kg / m 3 .

[0014] Preferably, the width of the heat insulation buffer layer gradually increases in the direction away from the heat absorption and dissipation layer, and a V-shaped structure is formed between the heat insulation buffer layers on both sides.

[0015] Preferably, the width of the heat insulation buffer layer gradually decreases in the direction away from the heat absorption and dissipation layer, and a V-shaped structure is formed between the heat insulation buffer layers on both sides.

[0016] Preferably, the ceramicized silicone foam comprises the following components in parts by weight: 30-40 parts vinyl silicone oil, 10-20 parts silica, 20-50 parts nano-ceramic powder, 0.1-1.0 parts ethynylcyclohexanol, 1-10 parts hydrogen-containing silicone oil, 1-10 parts hydroxyl silicone oil, 0.1-1.0 parts platinum catalyst, 10-20 parts β-nepheline, and 1-8 parts halloysite nanotubes.

[0017] Preferably, the heat absorption and heat dissipation layer has multiple heat dissipation grooves arranged side by side at intervals. The inner wall of the heat dissipation groove has a pressure relief port communicating with the outside. The pressure relief port is inclined outward. A spherical airbag is installed inside the heat dissipation groove, and part of the spherical airbag extends outside the heat dissipation groove and is embedded in the heat insulation buffer layer. The spherical airbag is filled with heat-absorbing liquid.

[0018] Preferably, the heat-absorbing and heat-dissipating layer is embedded with a buffer protrusion, and the top end of the buffer protrusion extends outside the heat-absorbing and heat-dissipating layer and is embedded in the heat-insulating buffer layer;

[0019] The heat-absorbing and heat-dissipating layer is provided with a liquid guiding channel. The inner cavity of the buffer protrusion is connected to the inner cavity of the spherical airbag through the liquid guiding channel, and the heat-absorbing liquid can flow between the buffer protrusion and the spherical airbag through the liquid guiding channel.

[0020] Preferably, the endothermic liquid is composed of phase change material, sodium chloride, TiO2 particles and water; the mass ratio of the phase change material, sodium chloride, TiO2 particles and water is (15-45):(5-15):(10-30):(40-60).

[0021] Preferably, the phase change material is a mixture of gallium, indium bismuth tin alloy and ortho-decanoic acid, wherein the mass ratio of gallium, indium bismuth tin alloy and ortho-decanoic acid is (1-2):(1-2):(2-4).

[0022] Preferably, the heat-absorbing and heat-dissipating layer comprises the following components in the indicated weight ratios: 40 parts aluminum nitride powder, 15 parts cubic boron nitride powder, 5 parts graphene nanosheets, 20 parts polyimide resin, 5 parts silane coupling agent, 10 parts nano-sized silver powder, and 5 parts carbon nanotubes.

[0023] Preferably, the phase change material can be dispersed in the solution in particulate form, with a particle size range of 1 μm to 100 μm; the TiO2 particles have a particle size range of 0.1 μm to 10 μm.

[0024] Preferably, the multifunctional protective pad is fixed to the battery cell using thermally conductive silicone.

[0025] Compared with the prior art, the present invention has at least the following beneficial effects:

[0026] 1) This invention adds multiple multifunctional protective pads spaced apart between adjacent battery cells. On the one hand, the protective pads form a buffer area between adjacent battery cells, forming a spring-like buffer protection structure, which effectively reduces the direct impact of mechanical vibration, impact or battery thermal expansion on the battery cells, thereby improving the safety and durability of the entire battery pack. On the other hand, it can effectively improve the heat dissipation performance and thermal insulation performance of the battery pack, preventing thermal runaway of the battery pack.

[0027] 2) The multifunctional protective pad of the present invention includes a heat-absorbing and heat-dissipating layer and a heat dissipation gap is formed between adjacent protective pads. The heat-absorbing and heat-dissipating layer is constructed by using a material with high thermal conductivity, which can quickly absorb and disperse the heat generated by the battery cells and reduce the formation of local hot spots. The heat dissipation gap is formed between adjacent multifunctional protective pads, so that heat can be transferred more effectively inside the battery pack and dissipated into the environment. These gaps act as heat flow channels, helping to reduce heat accumulation between battery cells, prevent overheating, and thus maintain the performance and life of the battery.

[0028] 3) This invention uses ceramicized silicone foam to make a heat insulation buffer layer. Under normal conditions, the silicone foam is in a compressed state, which can not only absorb the stress when the battery cell is working, but also provide a relatively heat-insulating environment for the battery cell due to the low thermal conductivity of the silicone foam. When a single battery runs away, the foam is in a ceramicized state at high temperature, forming a hard and heat-resistant insulator, which can block fire and heat, so that the temperature of the cold side is lower than the runaway temperature of the adjacent battery, thereby protecting the adjacent batteries and avoiding thermal runaway of the battery pack.

[0029] 4) The heat insulation buffer layer of this invention adopts a multi-layer ceramicized silica foam with decreasing density design (ρ1>ρ2>ρ3), and controls the specific density combination of each layer. This not only provides excellent thermal insulation and buffering performance, but also helps to absorb and disperse stress layer by layer, thereby protecting the battery cells from hot spots and stress, and further improving the safety and reliability of the battery. Specifically, the high-density first ceramicized silica foam can first receive and disperse external impact energy, reducing the direct transmission of impact force to the battery cells; the medium-density second ceramicized silica foam can further absorb and disperse the remaining impact energy; and the low-density third ceramicized silica foam has extremely high energy absorption capacity, ultimately absorbing and dispersing the remaining impact energy, protecting the battery cells. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the structure of a new energy battery pack according to an embodiment of the present invention;

[0031] Figure 2 This is a top view of a new energy battery pack according to an embodiment of the present invention;

[0032] Figure 3 This is a side view of a new energy battery pack according to an embodiment of the present invention;

[0033] Figure 4 This is a schematic diagram of the structure of a new energy battery pack according to another embodiment of the present invention;

[0034] Figure 5 This is a top view of a new energy battery pack according to another embodiment of the present invention;

[0035] Figure 6 This is a schematic diagram of the structure of a new energy battery pack when it expands according to another embodiment of the present invention;

[0036] Figure 7 This is a schematic diagram of the structure of a multifunctional protective pad according to an embodiment of the present invention;

[0037] Figure 8 This is a schematic cross-sectional view of the multifunctional protective pad according to one embodiment of the present invention.

[0038] Figure 9 for Figure 8 A magnified view of part A in the middle.

[0039] In the diagram: 1. Battery cell; 2. Multifunctional protective pad; 21. Heat absorption and dissipation layer; 211. Heat dissipation groove; 212. Pressure relief port; 213. Spherical airbag; 214. Buffer protrusion; 215. Liquid guide channel; 22. Heat insulation buffer layer; 221. First ceramicized silicone foam; 222. Second ceramicized silicone foam; 223. Third ceramicized silicone foam; 3. Heat dissipation gap. Detailed Implementation

[0040] 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.

[0041] Please see the appendix Figures 1-9 This embodiment provides a new energy battery pack with high safety performance, including a frame and a battery pack placed inside the frame. The battery pack includes multiple battery cells 1 stacked sequentially. At least two multi-functional protective pads 2 are provided between two adjacent battery cells 1, and a heat dissipation gap 3 is formed between two adjacent multi-functional protective pads 2. The multi-functional protective pad 2 includes a heat absorption and heat dissipation layer 21 and a heat insulation buffer layer 22 provided on both sides of the heat absorption and heat dissipation layer 21.

[0042] The heat insulation buffer layer 22 is made of ceramicized silicone foam, including a first ceramicized silicone foam 221, a second ceramicized silicone foam 222, and a third ceramicized silicone foam 223 arranged sequentially from the inside out. The densities ρ1 of the first ceramicized silicone foam 221, ρ2 of the second ceramicized silicone foam 222, and ρ3 of the third ceramicized silicone foam 223 satisfy the relationship: ρ1 > ρ2 > ρ3; and the density ρ1 of the first ceramicized silicone foam 221 is 300 kg / m³. 3~400kg / m 3 The density ρ2 of the second ceramicized silicone foam 222 is 200 kg / m³. 3 ~300kg / m 3 The density ρ3 of the third ceramicized silicone foam 223 is 100 kg / m³. 3 ~200kg / m 3 .

[0043] The layers of the multifunctional protective pad 2 can be integrated into a sheet structure through a well-known hot-press bonding process or spraying process.

[0044] like Figures 1-3 As shown, in one embodiment according to this application, the width of the heat insulation buffer layer 22 gradually increases in the direction away from the heat absorption and dissipation layer 21, and a V-shaped structure is formed between the two sides of the heat insulation buffer layer 22. This V-shaped structure design, where the width of the heat insulation buffer layer 22 gradually increases in the direction away from the heat absorption and dissipation layer 21, helps to form a more efficient heat flow channel and promotes uniform heat distribution.

[0045] like Figures 4-6 As shown, in another embodiment according to this application, the width of the heat insulation buffer layer 22 gradually decreases in the direction away from the heat absorption and dissipation layer 21, and a V-shaped structure is formed between the two sides of the heat insulation buffer layer 22. This V-shaped structure design, where the width of the heat insulation buffer layer 22 gradually increases in the direction away from the heat absorption and dissipation layer 21, not only helps to form a more efficient heat flow channel and promotes uniform heat distribution, but also creates an expansion space adapted to the battery cell 1 (the central part of the large surface of the battery cell 1 expands more, while the sides expand less, resulting in an overall arc-shaped expansion), further improving the buffering performance and anti-expansion performance of the battery pack.

[0046] In one embodiment of this application, the first ceramicized silicone foam 221, the second ceramicized silicone foam 222, and the third ceramicized silicone foam 223 are all provided with staggered pore structures. The porosity Q1 of the first ceramicized silicone foam 221, the porosity Q2 of the second ceramicized silicone foam 222, and the porosity Q3 of the third ceramicized silicone foam 223 satisfy the relationship: Q1 < Q2 < Q3; and the porosity Q1 of the first ceramicized silicone foam 221 is 20% to 30%, preferably 25%; the porosity Q2 of the second ceramicized silicone foam 222 is 30% to 50%, preferably 40%; and the porosity Q3 of the third ceramicized silicone foam 223 is 50% to 70%, preferably 60%. The staggered pore structure design not only improves buffering performance but also facilitates heat dissipation and gas flow, thereby enhancing heat dissipation. Furthermore, by innovatively combining the porosity and density of each layer, this application can achieve the effect of absorbing and dispersing stress layer by layer, thus significantly improving the buffering protection performance of the battery pack and ensuring the safety and reliability of the battery module.

[0047] In one embodiment of this application, the ceramicized silicone foam comprises the following components in parts by weight: 30-40 parts vinyl silicone oil, 10-20 parts silica, 20-50 parts nano-ceramic powder, 0.1-1.0 parts ethynylcyclohexanol, 1-10 parts hydrogen-containing silicone oil, 1-10 parts hydroxyl silicone oil, 0.1-1.0 parts platinum catalyst, 10-20 parts β-nepheline, and 1-8 parts halloysite nanotubes. The ceramicized silicone foam provided by this invention not only exhibits good elasticity under normal operating conditions, providing excellent buffering protection for the battery cell 1, but also, at high temperatures, rapidly forms a self-supporting foam ceramic body while maintaining a high degree of cell structure retention, thus exhibiting excellent heat insulation and flame retardant effects. Furthermore, it can withstand flames above 1300°C for extended periods, effectively isolating fire and temperature transmission, controlling the ignition range within a single battery compartment, and preventing adjacent batteries from igniting.

[0048] Vinyl silicone oil serves as the primary polymer matrix, providing the necessary elasticity and flexibility in the foaming system. It can also enhance the material's mechanical strength by undergoing an addition reaction with hydrogen-containing silicone oil to form a cross-linked structure. Silica, acting as a reinforcing agent, increases the composite material's tear resistance and abrasion resistance while improving the silicone rubber's compression resistance, making the material less prone to deformation even under high loads. Nano-ceramic powder acts as a flame retardant, promoting the formation of a hard ceramic layer on the material surface at high temperatures, effectively preventing further propagation of flames and heat. Ethynylcyclohexanol acts as an inhibitor, controlling the polymerization rate and preventing structural instability caused by excessively rapid reactions. Hydrogen-containing silicone oil, as a cross-linking agent, reacts with vinyl silicone oil to form a silicone rubber network structure, enhancing the material's overall mechanical properties and thermal stability. Hydroxyl silicone oil acts as a foaming agent in this system, decomposing upon heating to produce gas and form a foam structure, thus providing good cushioning performance and low density. Platinum catalysts catalyze the addition crosslinking reaction of vinyl silicone oil and hydrogen-containing silicone oil, improving reaction efficiency and uniformity, and ensuring consistent material properties. β-Lithium nepheline, as a ceramic-forming agent, can promote the transformation of silicone rubber into ceramic at high temperatures, enhancing the material's high-temperature resistance and structural stability. Halloysite nanotubes, as a pore structure stabilizer, can form a uniformly distributed support structure in the material, enhancing pore structure stability and preventing collapse under high temperature or mechanical pressure.

[0049] Therefore, through these specific components and their synergistic effect, the silicone foam of this invention not only maintains excellent elasticity and flexibility, effectively protecting the battery cell 1, but also significantly improves the material's performance under extreme conditions. Especially in fire scenarios, this material can rapidly form a self-supporting foam ceramic body, greatly enhancing its heat insulation and flame retardant capabilities. This foam ceramic body can maintain its structural integrity and flame retardancy when subjected to high temperatures or direct flame irradiation, unlike traditional silicone foam which may crack, deform, collapse, or even pulverize under the same conditions, thus losing its protective ability.

[0050] The method for preparing the ceramicized silicone foam includes the following steps:

[0051] Step S1: Add vinyl silicone oil, silica, nano-ceramic powder, and β-nepheline to a kneader and knead into a ball at 100-150°C. Cool to obtain the base adhesive.

[0052] Step S2: Stir and mix hydroxyl silicone oil and halloysite nanotubes to obtain a foaming mixture; wherein the stirring speed is 23000-26000 r / min and the mixing time is 10-25 s;

[0053] Step S3: Add the above foaming mixture, ethynylcyclohexanol, hydrogen-containing silicone oil, and platinum catalyst to the base adhesive, mix evenly, and obtain the adhesive compound;

[0054] Step S4: The rubber compound is vulcanized and foamed using casting, calendering or molding processes to obtain the ceramicized silicone foam.

[0055] The ceramicized silicone foam prepared by this invention has the following advantages:

[0056] 1) Excellent mechanical properties and elasticity: Due to the cross-linked structure of vinyl silicone oil and hydrogen-containing silicone oil, coupled with the reinforcing effect of silica, the silicone foam of the present invention has good elasticity and resistance to mechanical stress, which enables it to maintain its original shape and function after long-term use or repeated compression.

[0057] 2) Highly efficient flame retardant and heat insulation capabilities: The addition of nano-ceramic powder and β-lithium nepheline enables the material to quickly form a protective ceramic layer when subjected to high temperatures or flames. This structure not only effectively isolates the flames but also reduces heat transfer, protecting the internal structure from damage.

[0058] 3) Highly stable foam structure: The foam structure is formed by the gas generated from the decomposition of hydroxyl silicone oil, and its stability is enhanced by halloysite nanotubes, so that the foam is not easy to collapse even at high temperature and maintains a high cell structure retention rate.

[0059] 4) Excellent heat resistance: The controlled polymerization rate of ethynylcyclohexanol and the efficient catalytic effect of platinum catalyst ensure the uniform formation and stability of the silicone rubber network structure, thus maintaining performance even under extreme high temperature environments.

[0060] In one embodiment of this application, the heat-absorbing and heat-dissipating layer 21 has a plurality of heat dissipation grooves 211 arranged side by side at intervals. The inner wall of the heat dissipation groove 211 has a pressure relief port 212 communicating with the outside. The pressure relief port 212 is inclined outward. A spherical airbag 213 is installed inside the heat dissipation groove 211, and part of the spherical surface of the spherical airbag 213 extends outside the heat dissipation groove 211 and is embedded in the heat insulation buffer layer 22. The spherical airbag 213 is filled with heat-absorbing liquid.

[0061] In one embodiment of this application, the heat-absorbing and heat-dissipating layer 21 is provided with a buffer protrusion 214, and the top end of the buffer protrusion 214 extends outside the heat-absorbing and heat-dissipating layer 21 and is embedded in the heat-insulating buffer layer 22; wherein, the buffer protrusion 214 can be made of a polymer material with good elasticity, such as EVA, polyurethane, etc., and the buffer protrusion 214 further enhances the buffering capacity of the heat-absorbing and heat-dissipating layer 21, effectively absorbing and dispersing stress.

[0062] The heat-absorbing and heat-dissipating layer 21 is provided with a liquid-guiding channel 215. The inner cavity of the buffer protrusion 214 is connected to the inner cavity of the spherical airbag 213 through the liquid-guiding channel 215, and the heat-absorbing liquid can flow between the buffer protrusion 214 and the spherical airbag 213 through the liquid-guiding channel 215. The spherical airbag 213 can be made of a material with good thermal conductivity and elasticity, such as thermally conductive silicone, and is manufactured by injection molding, extrusion molding, or blow molding. The liquid-guiding channel 215 design enables the flow of heat-absorbing liquid between the buffer protrusion 214 and the spherical airbag 213, enhancing the efficiency and uniformity of heat dissipation.

[0063] In one embodiment of this application, the endothermic liquid is composed of a phase change material, sodium chloride, TiO2 particles, and water; the mass ratio of the phase change material, sodium chloride, TiO2 particles, and water is (15-45):(5-15):(10-30):(40-60); preferably 30:10:20:40. The endothermic liquid formulation contains a phase change material, which absorbs heat and undergoes a phase change at a specific temperature, effectively reducing the battery temperature. The addition of sodium chloride and TiO2 particles further enhances the heat absorption capacity and stability of the endothermic liquid.

[0064] In one embodiment of this application, the phase change material is a mixture of gallium, indium bismuth tin alloy, and ortho-capric acid, wherein the mass ratio of gallium, indium bismuth tin alloy, and ortho-capric acid is (1-2):(1-2):(2-4); preferably 1:1:3. The phase change material possesses excellent thermal absorption and conductivity properties, and the specific mass ratio ensures the stability and high efficiency of the endothermic liquid.

[0065] In one embodiment of this application, the phase change material can be dispersed in the solution in particulate form, with a particle size ranging from 1 μm to 100 μm; the TiO2 particles have a particle size ranging from 0.1 μm to 10 μm. Controlling the particle size ensures the uniformity of the endothermic liquid dispersion, further improving the efficiency and stability of thermal management.

[0066] In one embodiment of this application, the phase change material comprises sodium sulfate decahydrate, multi-walled carbon nanotubes, sodium carboxymethyl cellulose, and polyvinyl alcohol, wherein the mass percentages of sodium sulfate decahydrate, multi-walled carbon nanotubes, sodium carboxymethyl cellulose, and polyvinyl alcohol are 80-85%:5-10%:5-10%:5-10%, preferably 85%:5%:5%:5%. Sodium sulfate decahydrate, as the main phase change material, has a moderate phase change temperature and a high latent heat of phase change, enabling it to significantly absorb heat and thus reduce the battery pack temperature. Multi-walled carbon nanotubes improve the thermal conductivity of the phase change material, ensuring rapid heat diffusion within the material, making the phase change process more uniform and efficient. Sodium carboxymethyl cellulose, as a stabilizer, prevents crystallization deformation and phase separation during repeated use of the phase change material, improving its mechanical strength and stability. Polyvinyl alcohol, as a dispersant, ensures uniform dispersion of multi-walled carbon nanotubes and other additives in the phase change material, preventing aggregation and sedimentation, and improving the overall performance of the material.

[0067] In one embodiment of this application, the endothermic liquid comprises the following components by weight percentage: 20% paraffin wax, 5% sodium chloride, 10% hexagonal boron nitride nanosheets, 2% polyvinyl alcohol, and the balance being water. Paraffin wax, as a phase change material, can absorb a large amount of heat, improving the overall heat dissipation effect; sodium chloride enhances the overall thermal conductivity and lowers the freezing point of water, preventing the solution from freezing in low-temperature environments; hexagonal boron nitride nanosheets significantly improve the thermal conductivity of the endothermic liquid, ensuring rapid heat dispersion within the solution and preventing localized overheating; polyvinyl alcohol ensures uniform dispersion of the hexagonal boron nitride nanosheets in the solution, preventing aggregation and sedimentation, and improving the overall performance and stability of the solution; water, as the matrix solution, provides good fluidity and thermal conductivity, ensuring uniform dispersion of other components.

[0068] In one embodiment of this application, the heat-absorbing and heat-dissipating layer 21 comprises the following components in parts by weight: 40 parts aluminum nitride powder, 15 parts cubic boron nitride powder, 5 parts graphene nanosheets, 20 parts polyimide resin, 5 parts silane coupling agent, 10 parts nanoscale silver powder, and 5 parts carbon nanotubes.

[0069] This material combines aluminum nitride, cubic boron nitride, graphene nanosheets, nanoscale silver powder, and carbon nanotubes to achieve a balance of high thermal conductivity, high-temperature resistance, and mechanical strength. Aluminum nitride and cubic boron nitride, with their high thermal conductivity, enhance heat dissipation efficiency, while graphene nanosheets and carbon nanotubes further improve thermal conductivity. Polyimide resin is used as a high-temperature resistant matrix material, working in conjunction with the high thermal conductivity filler to provide excellent heat dissipation and high-temperature resistance. A silane coupling agent is used to modify the surface of the filler, improving the interfacial adhesion between the filler and the matrix and enhancing the overall performance of the material. Furthermore, the synergistic effect of the components forms a highly efficient thermally conductive network, further improving the material's thermal conductivity and heat dissipation performance.

[0070] The method for preparing the heat absorption and dissipation layer 21 is as follows:

[0071] Step 1: Pre-processing

[0072] Materials preparation:

[0073] Weigh aluminum nitride powder, cubic boron nitride powder, graphene nanosheets, nanoscale silver powder, and carbon nanotubes according to the specified proportions and set aside.

[0074] Prepare the polyimide resin and silane coupling agent.

[0075] Surface modification:

[0076] The fillers (aluminum nitride, cubic boron nitride, graphene nanosheets, nanoscale silver powder and carbon nanotubes) were mixed with silane coupling agents in anhydrous ethanol and stirred for 2 hours to perform surface modification.

[0077] The modified filler was dried at 80°C to remove residual ethanol.

[0078] Step 2: Mixing and Dispersing

[0079] Mixed packing:

[0080] Mix the modified fillers using a high-speed mixer or ball mill to ensure uniform dispersion; control the mixing time to more than 2 hours to ensure that all components are fully mixed.

[0081] Add matrix material:

[0082] The polyimide resin was dissolved in N-methylpyrrolidone (NMP) to form a homogeneous solution;

[0083] The mixed filler is gradually added to the polyimide solution, and stirring is continued until a uniform slurry is formed.

[0084] Step 3: Molding and Curing

[0085] The well-mixed slurry is evenly coated onto the aluminum plate;

[0086] The coated aluminum plate was dried at 80°C for 2 hours to allow the NMP solvent to evaporate completely.

[0087] Then, the aluminum plate is placed in an oven and cured at 300°C for 2 hours to allow the polyimide resin to fully crosslink and cure, thus obtaining the heat-absorbing and heat-dissipating layer 21.

[0088] In one embodiment of this application, the heat-absorbing and heat-dissipating layer 21 may also be made of a metal or alloy material with high thermal conductivity and heat dissipation performance, such as aluminum, copper and their alloys.

[0089] In one embodiment of this application, the multifunctional protective pad 2 is fixed to the battery cell 1 by thermally conductive silicone. The thermally conductive silicone not only fixes the multifunctional protective pad 2 to the battery cell 1, but also effectively improves the thermal conductivity and heat dissipation of the battery cell 1.

[0090] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0091] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A new energy battery pack, characterized in that, It includes multiple battery cells stacked sequentially, with at least two spaced-apart multifunctional protective pads between adjacent battery cells, and a heat dissipation gap formed between adjacent multifunctional protective pads; the multifunctional protective pad includes a heat absorption and heat dissipation layer and a heat insulation buffer layer disposed on both sides of the heat absorption and heat dissipation layer. The heat insulation buffer layer is made of ceramicized silicone foam, including a first ceramicized silicone foam, a second ceramicized silicone foam, and a third ceramicized silicone foam arranged sequentially from the inside out. The densities ρ1 of the first ceramicized silicone foam, ρ2 of the second ceramicized silicone foam, and ρ3 of the third ceramicized silicone foam satisfy the relationship: ρ1 > ρ2 > ρ3; and the density ρ1 of the first ceramicized silicone foam is 300 kg / m³ to 400 kg / m³; the density ρ2 of the second ceramicized silicone foam is 200 kg / m³ to 300 kg / m³; and the density ρ3 of the third ceramicized silicone foam is 100 kg / m³ to 200 kg / m³. The ceramicized silicone foam comprises the following components in parts by weight: 30-40 parts vinyl silicone oil, 10-20 parts silica, 20-50 parts nano-ceramic powder, 0.1-1.0 parts ethynylcyclohexanol, 1-10 parts hydrogen-containing silicone oil, 1-10 parts hydroxyl silicone oil, 0.1-1.0 parts platinum catalyst, 10-20 parts β-nepheline, and 1-8 parts halloysite nanotubes; The heat absorption and heat dissipation layer has multiple heat dissipation grooves arranged side by side at intervals. The inner wall of the heat dissipation groove has a pressure relief port that communicates with the outside. The pressure relief port is inclined outward. A spherical airbag is installed inside the heat dissipation groove, and part of the spherical airbag extends outside the heat dissipation groove and is embedded in the heat insulation buffer layer. The spherical airbag is filled with heat-absorbing liquid.

2. The new energy battery pack according to claim 1, characterized in that: The width of the heat insulation buffer layer gradually increases in the direction away from the heat absorption and dissipation layer, and a V-shaped structure is formed between the heat insulation buffer layers on both sides.

3. The new energy battery pack according to claim 1, characterized in that: The width of the heat insulation buffer layer gradually decreases in the direction away from the heat absorption and dissipation layer, and a V-shaped structure is formed between the heat insulation buffer layers on both sides.

4. The new energy battery pack according to claim 1, characterized in that: The heat-absorbing and heat-dissipating layer is embedded with a buffer protrusion, and the top of the buffer protrusion extends outside the heat-absorbing and heat-dissipating layer and is embedded in the heat-insulating buffer layer. The heat-absorbing and heat-dissipating layer is provided with a liquid guiding channel. The inner cavity of the buffer protrusion is connected to the inner cavity of the spherical airbag through the liquid guiding channel, and the heat-absorbing liquid can flow between the buffer protrusion and the spherical airbag through the liquid guiding channel.

5. The new energy battery pack according to claim 1, characterized in that: The endothermic liquid is composed of phase change material, sodium chloride, and Composed of particles and water; the phase change material, sodium chloride, The mass ratio of particles to water is (15~45):(5~15):(10~30):(40~60).

6. The new energy battery pack according to claim 5, characterized in that: The phase change material is a mixture of gallium, indium bismuth tin alloy and ortho-capric acid, and the mass ratio of gallium, indium bismuth tin alloy and ortho-capric acid is (1~2):(1~2):(2~4).

7. The new energy battery pack according to claim 1, characterized in that: The heat absorption and heat dissipation layer comprises the following components in the indicated weight ratios: 40 parts aluminum nitride powder, 15 parts cubic boron nitride powder, 5 parts graphene nanosheets, 20 parts polyimide resin, 5 parts silane coupling agent, 10 parts nano-sized silver powder, and 5 parts carbon nanotubes.

8. The new energy battery pack according to claim 1, characterized in that: The multifunctional protective pad is fixed to the battery cell by thermally conductive silicone.

Images