Preparation method and application of microporous aperture copper foam

Abstract

This invention belongs to the field of foam metal production and processing technology, specifically relating to a method for preparing micron-sized foam copper and its application. The method for preparing micron-sized foam copper includes the following steps: mixing: mixing and stirring copper powder, modified polyurethane microspheres, and adhesive; compounding and calendering, pre-drying and precision rolling, sintering, cleaning, drying, and slicing. The foam copper obtained by the method of this invention has micron-sized pores, high porosity, large specific surface area, and good thermal insulation properties.

Description

Technical Field

[0001] This invention belongs to the field of foam metal production and processing technology, specifically relating to a method for preparing micron-sized foam copper and its application. Background Technology

[0002] Foamed metal is a porous metallic material that combines the mechanical properties of metals with the advantages of porous materials. Foamed copper, a type of foamed metal material, is characterized by numerous interconnected or non-interconnected pores distributed within a copper matrix. It combines the superior properties of copper and porous materials, making it a novel functional structural material. Compared to traditional metallic copper, foamed copper significantly reduces weight while retaining good ductility, electrical and thermal conductivity, and chemical stability. It also possesses high specific surface area and high impact strength. With the rapid development of my country's industry and science and technology, especially the advancements in microelectronics and integrated circuits, the demand for foamed copper materials with complex structures and excellent properties in high-tech fields is increasing. It can be widely used in heat dissipation and heat exchange materials for electronic components such as CPUs, graphics cards, and LEDs; phase change energy storage materials; lithium-ion or fuel cell electrode materials; noise reduction materials; electromagnetic shielding materials; catalysts; and carriers. Therefore, foamed copper materials have been extensively studied.

[0003] Patent CN101608271B discloses a method for preparing through-hole copper foam. The method uses electrolytic copper powder and NaCl particles as raw materials. The NaCl particles are mixed evenly with the electrolytic copper powder and additives, then pressed into a green body. This green body is sintered in an argon atmosphere in a sintering furnace. The sintered material is then placed in a circulating hot water device to dissolve the NaCl particles, followed by washing in an ultrasonic water bath and acetone cleaning, and finally drying to obtain the final product. This invention, using NaCl as a pore-forming agent, typically results in a closed-cell structure, making it difficult to achieve a highly interconnected pore structure, thus limiting the material's application range.

[0004] Patent CN106180745B discloses a foamed copper powder and its preparation method. This invention uses copper oxide powder of different particle sizes as raw materials, with the particle size of the copper oxide powder being 5-75μm. The foamed copper powder of this invention does not require or only requires the addition of a small amount of pore-forming agent, and does not affect the material properties and applications of the copper matrix. The foamed copper powder prepared has high porosity and small pore size. The process is simple, the cost is low, and it does not pollute the environment. However, the foam obtained by this method requires the sintered copper to be crushed and sieved, which increases the post-processing steps and production costs.

[0005] Therefore, there is an urgent need to develop a method for preparing copper foam with high porosity and simple post-processing. Summary of the Invention

[0006] To overcome the shortcomings of the prior art, the present invention provides a method for preparing micron-sized copper foam. The copper foam prepared by this method has high porosity and specific surface area, good thermal insulation properties, and simple post-processing methods.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0008] The first aspect of this invention provides a method for preparing micron-sized copper foam, comprising the following steps:

[0009] S1. Mixing: Mix copper powder, modified polyurethane microspheres and adhesive for 30-50 minutes to obtain a mixture;

[0010] S2, Rubber mixing and calendering: The mixture obtained in step S1 is mixed and calendered;

[0011] S3. Pre-drying and finishing rolling: The material after calendering in step S2 is pre-dried and then finished rolled.

[0012] S4. Sintering: The material after fine rolling in step S3 is sintered under gas protection;

[0013] S5. Cleaning: Clean the material after sintering in step S4.

[0014] S6. Drying and slicing: Dry and slice the material after cleaning in step S5.

[0015] Preferably, the gas in step S4 is an inert gas or ammonia.

[0016] In some embodiments, the mass ratio of the copper powder, modified polyurethane microspheres, and adhesive is (5-8):(1-4):1.

[0017] In some embodiments, the method for preparing the modified polyurethane microspheres includes the following steps:

[0018] (1) Under an inert gas atmosphere, polyether diol is added to a reaction vessel, heated to 70-80℃, then isocyanate and catalyst are added, and the reaction is continued at 70-80℃ for 1.5-2.5h. After cooling to room temperature, the prepolymer is obtained.

[0019] (2) Add phloroglucinol and p-aminobenzoic acid to dichloromethane, then add sulfuric acid, react at 70-80℃ for 5-6 hours, wash and dry to obtain crosslinking agent;

[0020] (3) Add the crosslinking agent obtained in step (2) to ethanol, stir at room temperature for 15-20 min to obtain a mixture, then add the prepolymer obtained in step (1) dropwise to the mixture, react at room temperature for 2.5-3.5 h, centrifuge, wash and dry to obtain modified polyurethane microspheres.

[0021] Preferably, the mass ratio of the polyether diol to the isocyanate is 1:(1.5-3).

[0022] This invention prepares polyurethane microspheres via precipitation polymerization. The monomers and catalysts are mixed to form a homogeneous system. As the prepolymer reacts with the crosslinking agent, the molecular chains grow continuously. Once the critical chain length is reached, they precipitate from the solvent to form primary particles. These primary particles continue to grow by adsorbing the oligomers in the prepolymer continuously added to the solvent, eventually forming polyurethane microspheres. Preparing polymer microspheres using precipitation polymerization does not require the addition of any surfactants or stabilizers, and produces microspheres with clean surfaces. Product separation and post-processing are simple, which is beneficial for industrial production.

[0023] In some embodiments, the mass ratio of phloroglucinol to p-aminobenzoic acid is 1:(3-3.5).

[0024] In some embodiments, the mass ratio of the prepolymer to the crosslinking agent in step (3) is 1:(0.05-0.15).

[0025] Currently, common methods for preparing copper foam include powder metallurgy and electroplating. Powder metallurgy involves adding a foaming agent to molten copper, but the resulting foam may form a closed-cell structure with poor connectivity between pores. Electroplating replicates copper foam on a polyurethane foam skeleton using electrodeposition, but this process is complex, produces products with lower precision, and has lower production efficiency. This invention uses a specially structured crosslinking agent to prepare polyurethane microspheres, resulting in copper foam with high porosity and specific surface area, uniform pore size distribution, and good thermal insulation properties. One possible reason for this is the limitation of polyether diols. The mass ratio of the prepolymer to isocyanate makes the microspheres more uniform, resulting in uniform pore size in the sintered copper foam. Another reason is that the reaction between phloroglucinol and p-aminobenzoic acid, and the controlled ratio of the two, results in a crosslinking agent with multiple amino groups, increasing the degree of crosslinking of the modified polyurethane microspheres. This further increases the uniformity of the microspheres and enhances the compatibility between copper powder and the modified polyurethane microspheres, further increasing the porosity of the copper foam. In addition, by controlling the ratio of the prepolymer to the crosslinking agent, the modified polyurethane microspheres have good sphericity, and the pores of the sintered copper foam have good connectivity, further improving its thermal insulation performance.

[0026] In some embodiments, the method for preparing the adhesive includes the following steps:

[0027] 1) Under nitrogen protection, trans-3-chloro-2-propenylhydroxylamine, allyl alcohol, 4-dimethylaminopyridine, and hydroquinone were added to dichloromethane and stirred at 25-35°C for 35-37 h to obtain the functional monomer.

[0028] 2) Add the functional monomer, pentaerythritol triacrylate, and acrylic acid to a reaction vessel and stir at 60-70℃ for 30-60 min to obtain a mixture. Add the initiator to the solvent to obtain an initiator solution. Under a nitrogen atmosphere at 70-80℃, add half of the initiator solution by weight dropwise to the mixture and stir for 0.5-1.5 h. Then add the remaining initiator solution and stir for 4-5 h at 80-90℃. After cooling to 30-40℃, add isocyanate and solvent to obtain the adhesive.

[0029] Preferably, the mass ratio of trans-3-chloro-2-propenylhydroxylamine to allyl alcohol is 1:(0.54-0.7).

[0030] To improve the bonding strength of the internal structure of copper foam and prevent cracking or loosening, adhesive needs to be added during the preparation of copper foam. However, ordinary adhesives often have limited compatibility with copper powder, resulting in limited filling effect on the pores of copper powder and affecting the uniformity of the formed copper foam material. This invention prepares a functional monomer for the preparation of adhesive, which is easier to bond with copper powder and reduces internal defects in copper foam. The possible reason is that the functional monomer increases the compatibility between adhesive and copper powder, making it easier for adhesive to penetrate into the interior of copper powder. In addition, the presence of a large number of amino and ester groups has a strong bonding force with copper powder. Even after calendering, the modified polyurethane microspheres, adhesive and copper powder can still be uniformly dispersed, which increases the porosity and specific surface area of ​​the sintered copper foam.

[0031] In some embodiments, the mass ratio of the functional monomer, pentaerythritol triacrylate and acrylic acid in step 2) is (7-10):(2-5):1.

[0032] This invention increases the compatibility of copper powder and modified polyurethane microspheres and enhances the bonding force among the three by limiting the mass ratio of functional monomers, pentaerythritol triacrylate and acrylic acid, without affecting subsequent processing.

[0033] In some embodiments, the pre-drying temperature in step S3 is 50-90°C, the time is 4-6 hours, and the finishing rolling pressure is 160-180 MPa.

[0034] In some embodiments, the sintering temperature in step S4 is first raised to 550-650°C at a heating rate of 4-6°C / min, and then raised to 800-900°C at a heating rate of 7-10°C / min, with a sintering time of 3-4 hours.

[0035] A second aspect of the present invention provides an application of micron-sized copper foam in lithium batteries.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] 1. This invention utilizes a microsphere sintering method to prepare a micron-sized foamed copper with high porosity and specific surface area, good thermal insulation performance, and the ability to uniformly coat polymer electrolytes on its surface, making it a promising candidate for use in lithium batteries.

[0038] 2. This invention uses a crosslinking agent with a special structure to prepare polyurethane microspheres, which solves the problem of poor compatibility between conventional polyurethane microspheres and copper powder. This results in copper foam with high porosity and specific surface area, and uniform pore size distribution. In addition, by limiting the ratio of prepolymer to crosslinking agent, the modified polyurethane microspheres have good sphericity, which solves the problem of poor connectivity between pores and limited thermal insulation in copper foam.

[0039] 3. This invention prepares a functional monomer for use in preparing adhesives. The adhesive is easier to combine with copper powder, reducing internal defects in the foamed copper. It solves the problem that ordinary adhesives have poor compatibility with copper powder and limited filling effect on the pores of copper powder. At the same time, the presence of a large number of amino and ester groups has a strong binding force with copper powder, solving the problems of cracking and uneven thickness that may occur during calendering. This results in sintered foamed copper with a large porosity and specific surface area. Detailed Implementation

[0040] The present invention will be described below with reference to specific embodiments. It should be noted that the examples and comparative examples below are for illustrative purposes only and are not intended to limit the invention. Other combinations and various modifications within the scope of the invention can be made without departing from its spirit or scope.

[0041] To facilitate implementation of this invention by those skilled in the art, some raw materials and manufacturers of the embodiments and comparative examples are described below:

[0042] The compounds and related reagents used in the following examples and comparative examples are all commercially available. The polyether diol used was PPG-200; the average particle size of the copper powder was 3 μm.

[0043] Preparation Example 1

[0044] The preparation method of modified polyurethane microspheres-1 includes the following steps:

[0045] (1) Under a nitrogen atmosphere, 10g of polyether diol was added to the reaction vessel, the temperature was raised to 75°C, and then 25g of hexamethylene diisocyanate and 0.3g of dibutyltin dilaurate were added. The reaction was continued at 75°C for 2 hours, and then cooled to room temperature to obtain the prepolymer.

[0046] (2) Add 10g of phloroglucinol and 34g of p-aminobenzoic acid to 300ml of dichloromethane, then add 5ml of 90wt% sulfuric acid, react at 75℃ for 5.5h, wash and dry to obtain the crosslinking agent;

[0047] (3) Add 1g of the crosslinking agent obtained in step (2) to 100ml of anhydrous ethanol, stir at room temperature for 18min to obtain a mixture, then add 10g of the prepolymer obtained in step (1) to the mixture, react at room temperature for 3h, centrifuge, wash and dry to obtain modified polyurethane microspheres-1.

[0048] Preparation Example 2

[0049] The preparation method of modified polyurethane microspheres-2 is the same as that in preparation example 1, except that the amount of p-aminobenzoic acid added is 27g.

[0050] Preparation Example 3

[0051] The preparation method of modified polyurethane microspheres-3 is the same as that in preparation example 1, except that the amount of crosslinking agent added is 1.8g.

[0052] Preparation Example 4

[0053] The preparation method of polyurethane microspheres includes the following steps:

[0054] Under a nitrogen atmosphere, 10g of polyether diol was added to a reaction vessel and heated to 75°C. Then, 25g of hexamethylene diisocyanate and 0.3g of dibutyltin dilaurate were added, and the reaction was continued at 75°C for 2 hours. After cooling to room temperature, a prepolymer was obtained. 10g of ethylenediamine was added to 100ml of anhydrous ethanol and stirred at room temperature for 18 minutes to obtain a mixture. Then, 10g of the prepolymer obtained in step (1) was added dropwise to the mixture and reacted at room temperature for 3 hours. After centrifugation, washing and drying were performed to obtain polyurethane microspheres.

[0055] Preparation Example 5

[0056] The preparation method of adhesive-1 includes the following steps:

[0057] 1) Under nitrogen protection, 10.7g of trans-3-chloro-2-propenylhydroxylamine, 7g of allyl alcohol, 0.2g of 4-dimethylaminopyridine, and 0.1g of hydroquinone were added to 100ml of dichloromethane and stirred at 30℃ for 36h to obtain the functional monomer.

[0058] 2) Add 8g of functional monomer, 4g of pentaerythritol triacrylate, and 10g of acrylic acid to a reaction vessel and stir at 65℃ for 45min to obtain a mixture; add 0.1g of azobisisobutyronitrile to 25ml of toluene to obtain an azobisisobutyronitrile solution; under a nitrogen atmosphere at 75℃, add half of the azobisisobutyronitrile solution dropwise to the entire mixture and stir for 1h, then add the remaining azobisisobutyronitrile solution and stir for 4.5h at 85℃, then cool to 35℃, add 8g of lysine diisocyanate and 50ml of toluene to obtain glue-1.

[0059] Preparation Example 6

[0060] The preparation method of glue-2 is the same as that of preparation example 5, except that the amount of functional monomer added is 12g.

[0061] Preparation Example 7

[0062] The preparation method of glue-3 includes the following steps:

[0063] 4g of pentaerythritol triacrylate and 10g of acrylic acid were added to a reaction vessel and stirred at 65°C for 45 min to obtain a mixture. 0.1g of azobisisobutyronitrile was added to 25ml of toluene to obtain an azobisisobutyronitrile solution. Under a nitrogen atmosphere at 75°C, half of the azobisisobutyronitrile solution was added dropwise to the entire mixture and stirred for 1 h. Then the remaining azobisisobutyronitrile solution was added and stirred at 85°C for 4.5 h. After cooling to 35°C, 8g of lysine diisocyanate and 50ml of toluene were added to obtain glue-3.

[0064] Example 1

[0065] A method for preparing micron-sized copper foam includes the following steps:

[0066] S1. Mixing: Mix 70g of copper powder, 20g of modified polyurethane microspheres-1 and 10g of adhesive-1 and stir for 40 minutes to obtain a mixture;

[0067] S2. Rubber mixing and calendering: All the mixture obtained in step S1 is mixed at 120°C and calendered at 40MPa.

[0068] S3. Pre-drying and finishing rolling: All materials after calendering in step S2 are pre-dried at 70°C for 5 hours and then finished rolled at a pressure of 170MPa.

[0069] S4. Sintering: Under ammonia protection, all the materials after the fine rolling in step S3 are sintered. The sintering temperature is first raised to 600℃ at a heating rate of 5℃ / min, and then raised to 850℃ at a heating rate of 9℃ / min. The sintering time is 3.5h.

[0070] S5. Cleaning: Clean the material after sintering in step S4.

[0071] S6. Drying and slicing: Dry and slice the material after cleaning in step S5.

[0072] Example 2

[0073] A method for preparing micron-sized copper foam includes the following steps:

[0074] S1. Mixing: Mix 50g of copper powder, 10g of modified polyurethane microspheres-1 and 10g of adhesive-1 for 30 minutes to obtain a mixture;

[0075] S2. Rubber mixing and calendering: All the mixture obtained in step S1 is mixed at 120°C and calendered at 40MPa.

[0076] S3. Pre-drying and finishing rolling: The material after calendering in step S2 is pre-dried at 50°C for 6 hours and then finished rolled at a pressure of 160MPa.

[0077] S4. Sintering: The material after fine rolling in step S3 is sintered under ammonia protection. The sintering temperature is first raised to 550℃ at a heating rate of 4℃ / min, and then raised to 800℃ at a heating rate of 7℃ / min. The sintering time is 4h.

[0078] S5. Cleaning: Clean the material after sintering in step S4.

[0079] S6. Drying and slicing: Dry and slice the material after cleaning in step S5.

[0080] Example 3

[0081] A method for preparing micron-sized copper foam includes the following steps:

[0082] S1. Mixing: Mix 80g of copper powder, 40g of modified polyurethane microspheres-1 and 10g of adhesive-1 for 50 minutes to obtain a mixture;

[0083] S2. Rubber mixing and calendering: All the mixture obtained in step S1 is mixed at 120°C and calendered at 40MPa.

[0084] S3. Pre-drying and finishing rolling: The material after calendering in step S2 is pre-dried at 90°C for 4 hours and then finished rolled at a pressure of 180MPa.

[0085] S4. Sintering: The material after fine rolling in step S3 is sintered under ammonia protection. The sintering temperature is first raised to 650℃ at a heating rate of 6℃ / min, and then raised to 900℃ at a heating rate of 10℃ / min. The sintering time is 3h.

[0086] S5. Cleaning: Clean the material after sintering in step S4.

[0087] S6. Drying and slicing: Dry and slice the material after cleaning in step S5.

[0088] Example 4

[0089] A method for preparing micron-sized copper foam, the specific implementation method is the same as in Example 1, except that modified polyurethane microspheres-1 are replaced with modified polyurethane microspheres-2 in equal amounts.

[0090] Example 5

[0091] A method for preparing micron-sized copper foam, the specific implementation method is the same as in Example 1, except that modified polyurethane microspheres-1 are replaced with modified polyurethane microspheres-3 in equal amounts.

[0092] Example 6

[0093] A method for preparing micron-sized copper foam, the specific implementation method is the same as in Example 1, except that glue-1 is replaced with glue-2 in equal amounts.

[0094] Example 7

[0095] A method for preparing micron-sized copper foam, the specific implementation method is the same as in Example 1, except that glue-1 is replaced with glue-3 in equal amounts.

[0096] Example 8

[0097] A method for preparing micron-sized copper foam, the specific implementation method is the same as in Example 1, except that the amount of modified polyurethane microspheres-1 added in step S1 is 110g.

[0098] Comparative Example 1

[0099] A method for preparing micron-sized copper foam, the specific implementation is the same as in Example 1, except that the modified polyurethane microspheres-1 are replaced with polyurethane microspheres in equal amounts.

[0100] Performance testing

[0101] 1. The porosity, pore size, and specific surface area of ​​the copper foam obtained in each embodiment and comparative example were obtained by gas adsorption method (BET method).

[0102] 2. The foamed copper obtained from each embodiment and comparative example was made into cylindrical samples with a diameter of 12.7 mm, and the thermal conductivity of the samples was tested using a laser thermal conductivity meter.

[0103] The experimental results are shown in Table 1.

[0104] Table 1

[0105]

[0106] A comparison of the experimental data from Examples 1-3 in Table 1 shows that the copper foam prepared by this method has a pore size in the micrometer range, with large porosity and specific surface area, and low thermal conductivity. A comparison of Example 4 with Example 1 shows that changing the ratio of phloroglucinol and p-aminobenzoic acid may alter the sphericity of the polyurethane microspheres, leading to changes in all properties of the sintered copper foam. A comparison of Example 5 with Example 1 shows that changing the ratio of prepolymer to crosslinking agent may alter the degree of crosslinking, potentially causing pore wall collapse, increased pore size, decreased porosity, and increased thermal conductivity during sintering. A comparison of Example 6 with Example 1 shows that changing the ratio of functional monomers, pentaerythritol triacrylate, and acrylic acid may weaken the bonding force with copper powder and modified polyurethane microspheres, leading to changes in calendering properties. During the process, internal cracking occurred, resulting in uneven pore size distribution, decreased porosity, specific surface area, and thermal insulation. A comparison of Example 7 and Example 1 shows that conventional adhesives have poor compatibility with copper powder, limiting their filling effect on the copper powder pores, leading to a decrease in the pore size, porosity, specific surface area, and thermal insulation of the foamed copper. A comparison of Example 8 and Example 1 shows that changing the ratio of copper powder, modified polyurethane microspheres, and adhesive increases the number of microspheres per unit volume and decreases the pore size, but may lead to incomplete sintering, forming a closed-cell structure with uneven pore distribution, decreased porosity and specific surface area, and consequently, a decrease in the thermal insulation of the foamed copper. A comparison of Comparative Example 1 and Example 1 shows that using conventional polyurethane microspheres results in poor compatibility with copper powder, leading to a decrease in all indicators of the foamed copper obtained after sintering.

[0107] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A method for preparing micron-sized copper foam, characterized in that, Includes the following steps: S1. Mixing: Mix copper powder, modified polyurethane microspheres and adhesive for 30-50 minutes to obtain a mixture; S2, Rubber mixing and calendering: The mixture obtained in step S1 is mixed and calendered; S3. Pre-drying and finishing rolling: The material after calendering in step S2 is pre-dried and then finished rolled. S4. Sintering: The material after fine rolling in step S3 is sintered under gas protection; S5. Cleaning: Clean the material after sintering in step S4. S6. Drying and slicing: Dry and slice the material cleaned in step S5. The preparation method of the modified polyurethane microspheres includes the following steps: (1) Under an inert gas atmosphere, polyether diol is added to the reaction vessel, heated to 70-80℃, then isocyanate and catalyst are added, and the reaction is continued at 70-80℃ for 1.5-2.5h. After cooling to room temperature, the prepolymer is obtained. (2) Add phloroglucinol and p-aminobenzoic acid to dichloromethane, then add sulfuric acid, react at 70-80℃ for 5-6 hours, wash and dry to obtain crosslinking agent; (3) Add the crosslinking agent obtained in step (2) to ethanol, stir at room temperature for 15-20 min to obtain a mixture, then add the prepolymer obtained in step (1) dropwise to the mixture, react at room temperature for 2.5-3.5 h, centrifuge, wash and dry to obtain modified polyurethane microspheres; The method for preparing the adhesive includes the following steps: 1) Under nitrogen protection, trans-3-chloro-2-propenylhydroxylamine, allyl alcohol, 4-dimethylaminopyridine, and hydroquinone were added to dichloromethane and stirred at 25-35°C for 35-37 h to obtain the functional monomer. 2) Add the functional monomer, pentaerythritol triacrylate, and acrylic acid to a reaction vessel and stir at 60-70℃ for 30-60 min to obtain a mixture. Add the initiator to the solvent to obtain an initiator solution. Under a nitrogen atmosphere at 70-80℃, add half of the initiator solution by weight dropwise to the mixture and stir for 0.5-1.5 h. Then add the remaining initiator solution and stir for 4-5 h at 80-90℃. After cooling to 30-40℃, add isocyanate and solvent to obtain the adhesive.

2. The method for preparing micron-sized copper foam according to claim 1, characterized in that, The mass ratio of copper powder, modified polyurethane microspheres, and adhesive is (5-8):(1-4):

1.

3. The method for preparing micron-sized copper foam according to claim 1, characterized in that, The mass ratio of phloroglucinol to p-aminobenzoic acid is 1:(3-3.5).

4. The method for preparing micron-sized copper foam according to claim 1, characterized in that, The mass ratio of the prepolymer to the crosslinking agent in step (3) is 1:(0.05-0.15).

5. The method for preparing micron-sized copper foam according to claim 1, characterized in that, The pre-drying temperature in step S3 is 50-90℃, and the finishing rolling pressure is 160-180MPa.

6. The method for preparing micron-sized copper foam according to claim 1, characterized in that, The sintering temperature mentioned in step S4 is first raised to 550-650℃ at a heating rate of 4-6℃ / min, and then raised to 800-900℃ at a heating rate of 7-10℃ / min, with a sintering time of 3-4h.

7. The application of micron-pore copper foam obtained by the method for preparing micron-pore copper foam according to any one of claims 1-6 in lithium batteries.

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