CN111048780A - Graphene conductive agent for lithium ion battery and preparation method thereof - Google Patents
Graphene conductive agent for lithium ion battery and preparation method thereof Download PDFInfo
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Abstract
The invention discloses a graphene conductive agent for a lithium ion battery and a preparation method thereof, and belongs to the technical field of electrochemistry. The graphene conductive agent is prepared by the following method: firstly, crushing and stripping graphene powder, then uniformly mixing the graphene powder with carbon nano tubes to obtain high-quality graphene-carbon nano tube powder, then mixing and dissolving the graphene-carbon nano tube powder with a dispersing agent, carrying out ultrasonic treatment and suction filtration on the obtained solution, carrying out supercritical treatment on the filtered solid for 2-6 hours, quickly reducing the pressure after the carbon dioxide circularly flows to reach a preset value, finally sequentially repeating the steps of supercritical treatment and quick pressure reduction, enabling the material to undergo multiple pressure increasing and reducing processes, finally discharging the mixed material in an autoclave, and carrying out sanding treatment. The graphene conductive agent for the lithium ion battery prepared by the invention has the advantages that the ultrahigh specific capacity is excellent in rate capability, the attenuation rate is only about 9% after 1000 cycles, and the good cycle stability is realized.
Description
Technical Field
The invention belongs to the technical field of electrochemistry, and particularly relates to a graphene conductive agent for a lithium ion battery and a preparation method thereof.
Background
The lithium ion power battery is a power supply for providing a power source for the tool, and is a product needing power driving, such as an electric automobile, an electric train, a power transmission substation and the like; has the advantages of high energy and power, high energy density, wide working temperature range (-30-65 ℃), long service life, safety, reliability and the like. However, in the research related to the development of the lithium ion battery cathode material, the capacity of the existing cathode electrode is limited, and the capacity of the novel cathode electrode is greatly attenuated in the charging and discharging process. In order to further improve the electrochemical performance of the lithium ion battery, and to provide the advantages of high energy density and long cycle life, further development of new electrode materials is required to improve the battery performance. The addition of a proper conductive agent into the electrode material can improve the conductivity of the electrode, reduce the polarization resistance in the battery and improve the electrochemical performance of the battery, thereby effectively solving the problem. The conductive agent generally used is a carbon material such as graphite, carbon black, or carbon nanotube having high conductivity.
The graphene conductive agent is concerned by more and more researchers due to the unique advantages of the graphene conductive agent, however, the graphene is easy to agglomerate, and the graphene conductive agent has the defect of difficult dispersion when being used as a conductive agent, so that the application of the graphene conductive agent is greatly limited. Therefore, how to ensure the dispersibility and uniformity of the graphene conductive agent is very important.
Disclosure of Invention
In view of the problems or defects of the prior art, the present invention aims to provide a graphene conductive agent for a lithium ion battery and a preparation method thereof. According to the invention, graphene is dispersed and peeled off under the assistance of a supercritical fluid method, and then the mixed powder is further dispersed by sanding through a sanding machine, so that the technical problems existing in the prior art are solved.
In order to achieve one of the above objects of the present invention, the present invention adopts the following technical solutions:
a preparation method of a graphene conductive agent for a lithium ion battery specifically comprises the following steps:
(1) pretreatment of graphene powder: feeding the graphene powder into a jet mill, and crushing and stripping at a certain temperature to obtain high-quality graphene powder which meets the requirement of particle size, has uniform layer number dispersion and good fluidity and is not easy to agglomerate;
(2) fully stirring and mixing the high-quality graphene powder obtained in the step (1) and the carbon nano tube in a high-speed mixing reactor to obtain high-quality graphene-carbon nano tube powder;
(3) dissolving the mixed powder consisting of the high-quality graphene-carbon nano tube powder obtained in the step (2) and a dispersing agent in a solvent, placing the obtained solution in an ultrasonic cleaning machine for ultrasonic treatment, carrying out suction filtration on the solution after ultrasonic treatment, and placing the filtered solid in a high-pressure kettle;
(4) pumping carbon dioxide into the high-pressure autoclave after the temperature in the high-pressure autoclave reaches a preset value, starting the carbon dioxide to circularly flow after the pressure in the high-pressure autoclave reaches the preset value, carrying out supercritical treatment for a period of time, and stirring materials in the high-pressure autoclave by using an ultrasonic or stirring device during reaction;
(5) after the carbon dioxide circularly flows to reach a preset value, quickly reducing the pressure to reduce the pressure in the kettle to normal pressure;
(6) repeating the step (4) and the step (5) in sequence to enable the materials to undergo multiple pressure increasing and reducing processes, and finally discharging the mixed materials in the high-pressure kettle;
(7) and (4) sending the mixed material obtained in the step (6) into a sand mill, and properly sanding for a period of time to obtain the graphene conductive agent for the lithium ion battery.
Further, according to the technical scheme, in the step (1), the jet mill is a circulating pipe type jet mill, the temperature is 15-25 ℃, and the time for crushing and stripping of the jet mill is 2-5 hours.
Further, according to the technical scheme, in the step (1), the conductivity of the high-quality graphene powder is 1500S/cm, and the thickness of the high-quality graphene powder is 1-5 nm.
Further, according to the technical scheme, in the step (2), the mass ratio of the high-quality graphene powder to the carbon nano tubes is 9: 1-1: 9.
Further, in the above technical scheme, in the step (3), the solvent is one or more of N-methylpyrrolidone, N-methylformamide, N-dimethylformamide, acetamide, N-methylacetamide, N-dimethylacetamide, ethanol, isopropanol, dichloromethane, and water.
Further, in the above technical scheme, in the step (3), the dispersant is one or more of sodium dodecyl sulfate, sodium dodecyl benzene sulfonate, sodium dodecyl sulfate, polyvinylpyrrolidone, ethyl cellulose, and sodium cholate.
Further, according to the technical scheme, in the step (3), the high-quality graphene-carbon nanotube powder and the dispersing agent are mixed according to the mass ratio of 1 (1-11), and the ratio of the mixed powder to the solvent is 1-6 g/L.
Further, according to the technical scheme, in the step (3), the ultrasonic temperature is 30-50 ℃, the ultrasonic power is 400-800W, and the ultrasonic time is 2-5 h.
Further, according to the technical scheme, in the step (4), the temperature preset value in the high-pressure kettle is 25-50 ℃, the pressure preset value in the high-pressure kettle is 5-30 MPa, and the supercritical processing time is 2-6 hours.
Further, in the technical scheme, in the step (5), the pressure reduction speed is 5-20 MPa/s.
Further, in the technical scheme, in the step (7), the sanding time is 3-5 hours.
The second purpose of the invention is to provide the graphene conductive agent for the lithium ion battery prepared by the method.
Compared with the prior art, the invention has the following beneficial effects:
(1) according to the invention, graphene powder is fed into a jet mill by adopting a jet milling and stripping method, is milled and stripped, the powder collides in a jet manner in a milling chamber to generate high-strength impact force, shearing force and friction force, the powder is screened in a grading chamber in the processes of repeated impact, cutting and friction in high-speed airflow, unqualified large-particle powder flows back to the milling chamber to continuously collide, a product meeting the particle size requirement is produced from a product outlet, and the high-quality graphene powder with uniform layer number dispersion, good fluidity, few defects, high electrical conductivity, difficult agglomeration and excellent electrochemical performance is obtained.
(2) The conductive additive composed of the high-quality graphene powder and the carbon nano tube and the active material are in a point-point or line-point contact mode, so that the electrode conductivity is greatly improved. The use amount can be reduced, and the integral conductivity of the electrode can be improved, so that the capacity, the multiplying power and the cycle performance of the battery are improved.
(3) The high-quality graphene powder and the carbon nano tube have higher electrical conductivity, can effectively exert respective advantages by combining the two, and overcome the problem that the single graphene electrode material has poor cycle performance and rate capability.
(4) According to the invention, by utilizing the advantages that the viscosity of the supercritical fluid is close to that of gas, the diffusion coefficient is large, the viscosity is small, the dielectric constant is large, the separation effect is good and the like, the prepared graphene conductive agent for the lithium ion battery shows ultrahigh specific capacity and excellent rate capability, the attenuation rate is only about 9% after 1000 cycles, and the good cycle stability is achieved.
(5) The preparation method is green and environment-friendly, the equipment and the process are simple and feasible, and the industrial production is easy to realize.
Drawings
Fig. 1 is a 0.2C-rate first charge-discharge curve of a battery assembled by using the graphene conductive agent obtained in example 1.
Fig. 2 is a 0.5C-rate first charge-discharge curve of a battery assembled by applying the graphene conductive agent obtained in example 2.
Detailed Description
The present invention will be described in further detail below with reference to examples. The present invention is implemented on the premise of the technology of the present invention, and the detailed embodiments and specific procedures are given to illustrate the inventive aspects of the present invention, but the scope of the present invention is not limited to the following embodiments.
Various modifications to the precise description of the invention will be readily apparent to those skilled in the art from the information contained herein without departing from the spirit and scope of the appended claims. It is to be understood that the scope of the invention is not limited to the procedures, properties, or components defined, as these embodiments, as well as others described, are intended to be merely illustrative of particular aspects of the invention. Indeed, various modifications of the embodiments of the invention which are obvious to those skilled in the art or related fields are intended to be covered by the scope of the appended claims.
For a better understanding of the invention, and not as a limitation on the scope thereof, all numbers expressing quantities, percentages, and other numerical values used in this application are to be understood as being modified in all instances by the term "about". Accordingly, unless expressly indicated otherwise, the numerical parameters set forth in the specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained. At the very least, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.
Materials, reagents and the like used in the following examples are commercially available unless otherwise specified. The carbon nanotube powder is a multi-walled carbon nanotube with a diameter of 10-15 nm and a purity of more than 99.8%, and is available from Jiangsu Tiannai science and technology limited.
Example 1
The preparation method of the graphene conductive agent for the lithium ion battery in the embodiment specifically comprises the following steps:
(1) pretreatment of graphene powder: feeding the graphene powder into a jet mill, and crushing and stripping for 2h to obtain high-quality graphene powder which meets the requirement on particle size, has uniform layer number dispersion and good fluidity and is not easy to agglomerate;
(2) fully stirring and mixing the 90mg high-quality graphene powder and the 10mg carbon nano tube obtained in the step (1) in a high-speed mixing reactor to obtain high-quality graphene-carbon nano tube powder;
(3) dissolving the mixed powder consisting of 25mg of the high-quality graphene-carbon nanotube powder obtained in the step (2) and 25mg of sodium dodecyl sulfate in 50mL of N-methylpyrrolidone, placing the solution in an ultrasonic cleaning machine for ultrasonic treatment for 3 hours at the ultrasonic temperature of 30 ℃ and the ultrasonic power of 500W, carrying out suction filtration on the solution after ultrasonic treatment, and putting the filtered solid into an autoclave;
(4) pumping carbon dioxide into the high-pressure kettle when the temperature in the high-pressure kettle reaches 25 ℃, enabling the carbon dioxide to start to circularly flow after the pressure in the high-pressure kettle reaches 5MPa, carrying out supercritical treatment for 2h, and stirring materials in the high-pressure reaction kettle by using an ultrasonic or stirring device during reaction;
(5) quickly reducing the pressure at the speed of 10MPa/s to reduce the pressure in the kettle to normal pressure;
(6) repeating the processes of the step (4) and the step (5) in sequence, so that the materials undergo multiple pressure increasing and reducing processes, and finally discharging the mixed materials in the high-pressure kettle;
(7) and (4) finally, sending the mixed material obtained in the step (6) into a sand mill for proper sand milling for 3.5 hours to obtain the graphene conductive agent for the lithium ion battery.
Example 2
The preparation method of the graphene conductive agent for the lithium ion battery in the embodiment specifically comprises the following steps:
(1) pretreatment of graphene powder: feeding the graphene powder into a jet mill, and crushing and stripping for 2.5 hours to obtain high-quality graphene powder which meets the requirement of particle size, has uniform layer number dispersion and good fluidity and is not easy to agglomerate;
(2) fully stirring and mixing the high-quality graphene powder 60mg and the carbon nano tube 10mg obtained in the step (1) in a high-speed mixing reactor to obtain high-quality graphene-carbon nano tube powder;
(3) dissolving the mixed powder consisting of 25mg of high-quality graphene-carbon nanotube powder and 50mg of sodium dodecyl sulfate obtained in the step (2) in 50mL of acetamide, placing the solution in an ultrasonic cleaning machine for ultrasonic treatment for 2h, wherein the ultrasonic temperature is 35 ℃, the ultrasonic power is 800W, carrying out suction filtration on the solution after ultrasonic treatment, and putting the filtered solid into an autoclave;
(4) pumping carbon dioxide into the high-pressure autoclave after the temperature in the high-pressure autoclave reaches 25 ℃, starting circulating flow of the carbon dioxide after the pressure in the high-pressure autoclave reaches 15MPa, carrying out supercritical treatment for 3h, and stirring materials in the high-pressure autoclave by using an ultrasonic or stirring device during reaction;
(5) rapidly reducing the pressure at the speed of 5MPa/s to reduce the pressure in the kettle to normal pressure;
(6) repeating the processes of the step (4) and the step (5) in sequence, so that the materials undergo multiple pressure increasing and reducing processes, and finally discharging the mixed materials in the high-pressure kettle;
(7) and (4) finally, sending the mixed material obtained in the step (6) into a sand mill for proper sand milling for 3 hours to obtain the graphene conductive agent for the lithium ion battery.
Example 3
The preparation method of the graphene conductive agent for the lithium ion battery in the embodiment specifically comprises the following steps:
(1) pretreatment of graphene powder: feeding the graphene powder into a jet mill, and crushing and stripping for 3 hours to obtain high-quality graphene powder which meets the requirement on particle size, is uniform in layer number dispersion, good in fluidity and not prone to agglomeration;
(2) fully stirring and mixing the 10mg high-quality graphene powder and 30mg carbon nano tube obtained in the step (1) in a high-speed mixing reactor to obtain high-quality graphene-carbon nano tube powder;
(3) dissolving the mixed powder consisting of 25mg of high-quality graphene-carbon nanotube powder and 100mg of polyvinylpyrrolidone obtained in the step (2) in 50mL of ethanol, placing the solution in an ultrasonic cleaning machine for ultrasonic treatment for 4h, wherein the ultrasonic temperature is 40 ℃, the ultrasonic power is 500W, carrying out suction filtration on the solution after ultrasonic treatment, and putting the filtered solid into a high-pressure kettle;
(4) pumping carbon dioxide into the high-pressure autoclave after the temperature in the high-pressure autoclave reaches 30 ℃, starting the circulating flow of the carbon dioxide after the pressure in the high-pressure autoclave reaches 20MPa, carrying out supercritical treatment for 4h, and stirring materials in the high-pressure autoclave by using an ultrasonic or stirring device during reaction;
(5) quickly reducing the pressure at the speed of 15MPa/s to reduce the pressure in the kettle to normal pressure;
(6) repeating the processes of the step (4) and the step (5) in sequence, so that the materials undergo multiple pressure increasing and reducing processes, and finally discharging the mixed materials in the high-pressure kettle;
(7) and (4) finally, sending the mixed material obtained in the step (6) into a sand mill for proper sand milling for 4 hours to obtain the graphene conductive agent for the lithium ion battery.
Example 4
The preparation method of the graphene conductive agent for the lithium ion battery in the embodiment specifically comprises the following steps:
(1) pretreatment of graphene powder: feeding the graphene powder into a jet mill, and crushing and stripping for 4 hours to obtain high-quality graphene powder which meets the requirement on particle size, is uniformly dispersed in the number of layers, has good fluidity and is not easy to agglomerate;
(2) fully stirring and mixing the 20mg of high-quality graphene powder obtained in the step (1) and 45mg of carbon nanotubes in a high-speed mixing reactor to obtain high-quality graphene-carbon nanotube powder;
(3) dissolving the mixed powder consisting of 25mg of high-quality graphene-carbon nanotube powder and 225mg of ethyl cellulose obtained in the step (2) in 50mL of isopropanol, placing the solution in an ultrasonic cleaning machine for ultrasonic treatment for 5 hours at the ultrasonic temperature of 45 ℃ and the ultrasonic power of 600W, carrying out suction filtration on the solution after ultrasonic treatment, and putting the filtered solid into an autoclave;
(4) pumping carbon dioxide into the high-pressure kettle when the temperature in the high-pressure kettle reaches 40 ℃, starting the circulating flow of the carbon dioxide after the pressure in the high-pressure kettle reaches 25MPa, carrying out supercritical treatment for 4h, and stirring materials in the high-pressure reaction kettle by using an ultrasonic or stirring device during reaction;
(5) quickly reducing the pressure at the speed of 10MPa/s to reduce the pressure in the kettle to normal pressure;
(6) repeating the processes of the step (4) and the step (5), so that the materials undergo multiple pressure increasing and reducing processes, and finally discharging the mixed materials in the high-pressure kettle;
(7) and (4) finally, sending the mixed material obtained in the step (6) into a sand mill for proper sand milling for 5 hours to obtain the graphene conductive agent for the lithium ion battery.
Example 5
The preparation method of the graphene conductive agent for the lithium ion battery in the embodiment specifically comprises the following steps:
(1) pretreatment of graphene powder: feeding the graphene powder into a jet mill, and crushing and stripping for 5 hours to obtain high-quality graphene powder which meets the requirement on particle size, is uniformly dispersed in the number of layers, has good fluidity and is not easy to agglomerate;
(2) fully stirring and mixing the 10mg high-quality graphene powder and the 90mg carbon nano tube obtained in the step (1) in a high-speed mixing reactor to obtain high-quality graphene-carbon nano tube powder;
(3) dissolving the mixed powder consisting of 25mg of high-quality graphene-carbon nanotube powder obtained in the step (2) and 275mg of sodium cholate in 50mL of dichloromethane, placing the solution in an ultrasonic cleaning machine for ultrasonic treatment for 5h, wherein the ultrasonic temperature is 50 ℃, the ultrasonic power is 400W, carrying out suction filtration on the solution after ultrasonic treatment, and putting the filtered solid into an autoclave;
(4) pumping carbon dioxide into the high-pressure autoclave when the temperature in the high-pressure autoclave reaches 50 ℃, starting circulating flow of the carbon dioxide after the pressure in the high-pressure autoclave reaches 30MPa, carrying out supercritical treatment for 6h, and stirring materials in the high-pressure autoclave by using an ultrasonic or stirring device during reaction;
(5) quickly reducing the pressure at the speed of 10MPa/s to reduce the pressure in the kettle to normal pressure;
(6) repeating the processes of the step (4) and the step (5), so that the materials undergo multiple pressure increasing and reducing processes, and finally discharging the mixed materials in the high-pressure kettle;
(7) and (4) finally, sending the mixed material obtained in the step (6) into a sand mill for proper sand milling for 5 hours to obtain the graphene conductive agent for the lithium ion battery.
Application example 1
The NCM523 active material is mixed with the graphene conductive agent and the binding agent polyvinylidene fluoride obtained in the embodiment 1 according to the mass ratio of 9: 0.5: 0.5, mixing evenly and coating on an aluminum foil to prepare the positive plate. A button cell is assembled by taking a lithium sheet as a counter electrode, a UB3025 membrane as a diaphragm and Ethylene Carbonate (EC) + dimethyl carbonate (DMC) + lithium hexafluorophosphate (LiPF6) as an electrolyte. And (3) carrying out constant current discharge test on the battery within the voltage range of 2.75-4.2V at room temperature (25 +/-2 ℃).
The test result is shown in figure 1, when the charge-discharge current density is 0.2C, the first discharge specific capacity is about 168mAh/g, and after 1000 cycles, the discharge specific capacity is still maintained at about 152mAh/g, so that the high-performance lithium ion battery has good cycle stability.
Application example 2
The NCM622 active material, the graphene conductive agent and the adhesive polyvinylidene fluoride in the embodiment 2 are uniformly mixed according to the mass ratio of 9: 0.5 and then coated on an aluminum foil to prepare the positive plate. A button cell is assembled by taking a lithium sheet as a counter electrode, a UB3025 membrane as a diaphragm and Ethylene Carbonate (EC) + dimethyl carbonate (DMC) + lithium hexafluorophosphate (LiPF6) as an electrolyte. And (3) carrying out constant current discharge test on the battery within the voltage range of 2.75-4.2V at room temperature (25 +/-2 ℃).
The test result is shown in figure 2, when the charge-discharge current density is 0.5C, the first discharge specific capacity is about 185mAh/g, and after 1000 cycles, the discharge specific capacity is still maintained at about 167mAh/g, so that the high-performance lithium ion battery has good cycle stability.
Claims (10)
1. A preparation method of a graphene conductive agent for a lithium ion battery is characterized by comprising the following steps: the method specifically comprises the following steps:
(1) pretreatment of graphene powder: feeding the graphene powder into a jet mill, and crushing and stripping at a certain temperature to obtain high-quality graphene powder which meets the requirement of particle size, has uniform layer number dispersion and good fluidity and is not easy to agglomerate;
(2) fully stirring and mixing the high-quality graphene powder obtained in the step (1) and the carbon nano tube in a high-speed mixing reactor to obtain high-quality graphene-carbon nano tube powder;
(3) dissolving the mixed powder consisting of the high-quality graphene-carbon nano tube powder obtained in the step (2) and a dispersing agent in a solvent, placing the obtained solution in an ultrasonic cleaning machine for ultrasonic treatment, carrying out suction filtration on the solution after ultrasonic treatment, and placing the filtered solid in a high-pressure kettle;
(4) pumping carbon dioxide into the high-pressure autoclave after the temperature in the high-pressure autoclave reaches a preset value, starting the carbon dioxide to circularly flow after the pressure in the high-pressure autoclave reaches the preset value, carrying out supercritical treatment for a period of time, and stirring materials in the high-pressure autoclave by using an ultrasonic or stirring device during reaction;
(5) after the carbon dioxide circularly flows to reach a preset value, quickly reducing the pressure to reduce the pressure in the kettle to normal pressure;
(6) repeating the step (4) and the step (5) in sequence to enable the materials to undergo multiple pressure increasing and reducing processes, and finally discharging the mixed materials in the high-pressure kettle;
(7) and (4) sending the mixed material obtained in the step (6) into a sand mill, and properly sanding for a period of time to obtain the graphene conductive agent for the lithium ion battery.
2. The method for preparing the graphene conductive agent for the lithium ion battery according to claim 1, wherein the method comprises the following steps: in the step (1), the conductivity of the high-quality graphene powder is 1500S/cm, and the thickness of the high-quality graphene powder is 1-5 nm.
3. The method for preparing the graphene conductive agent for the lithium ion battery according to claim 1, wherein the method comprises the following steps: in the step (2), the mass ratio of the high-quality graphene powder to the carbon nano tubes is 9: 1-1: 9.
4. The method for preparing the graphene conductive agent for the lithium ion battery according to claim 1, wherein the method comprises the following steps: in the step (3), the solvent is one or more of N-methylpyrrolidone, N-methylformamide, N-dimethylformamide, acetamide, N-methylacetamide, N-dimethylacetamide, ethanol, isopropanol, dichloromethane and water.
5. The method for preparing the graphene conductive agent for the lithium ion battery according to claim 1, wherein the method comprises the following steps: in the step (3), the dispersant is one or more of sodium dodecyl sulfate, sodium dodecyl benzene sulfonate, sodium dodecyl sulfate, polyvinylpyrrolidone, ethyl cellulose and sodium cholate.
6. The method for preparing the graphene conductive agent for the lithium ion battery according to claim 1, wherein the method comprises the following steps: and (3) mixing the high-quality graphene-carbon nanotube powder and a dispersing agent according to the mass ratio of 1 (1-11), wherein the ratio of the mixed powder to the solvent is 1-6 g/L.
7. The method for preparing the graphene conductive agent for the lithium ion battery according to claim 1, wherein the method comprises the following steps: in the step (4), the temperature preset value in the high-pressure autoclave is 25-50 ℃, the pressure preset value in the high-pressure autoclave is 5-30 MPa, and the supercritical processing time is 2-6 h.
8. The method for preparing the graphene conductive agent for the lithium ion battery according to claim 1, wherein the method comprises the following steps: in the step (5), the pressure reduction speed is 5-20 MPa/s.
9. The method for preparing the graphene conductive agent for the lithium ion battery according to claim 1, wherein the method comprises the following steps: in the step (7), the sanding time is 3-5 h.
10. The graphene conductive agent for the ion battery, which is prepared by the preparation method of the graphene conductive agent for the lithium ion battery according to any one of claims 1 to 9.
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| CN114538419A (en) * | 2020-11-26 | 2022-05-27 | 江苏天奈科技股份有限公司 | Preparation method and equipment of dispersible carbon nanotube powder |
| CN114792585A (en) * | 2022-01-20 | 2022-07-26 | 马国庆 | Preparation treatment process of graphene slurry with strong magnetic and electric properties |
| CN115744889A (en) * | 2022-11-30 | 2023-03-07 | 上海利物盛纳米科技有限公司 | Method for preparing graphene powder by combining sanding and high-pressure airflow |
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| CN114792585B (en) * | 2022-01-20 | 2024-05-24 | 中山市华洋塑胶颜料有限公司 | Graphene slurry preparation treatment process |
| CN115744889A (en) * | 2022-11-30 | 2023-03-07 | 上海利物盛纳米科技有限公司 | Method for preparing graphene powder by combining sanding and high-pressure airflow |
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