Pole piece slurry of high-capacity lithium battery for unmanned aerial vehicle and coating process of pole piece slurry

Abstract

The invention discloses pole piece slurry of a high-capacity lithium battery for an unmanned aerial vehicle and a coating process of the pole piece slurry, and belongs to the technical field of electrode materials, the pole piece slurry is prepared from the following raw materials in parts by mass: 5-8 parts of polybenzimidazole, 40-50 parts of dimethylacetamide, 15-20 parts of MOF-loaded composite graphene, 3-4 parts of carbon nanotubes and 5-10 parts of conductive carbon black; the MOF-loaded composite graphene is prepared by adsorbing and loading p-aminobenzoic acid with MOF composite graphene; the MOF composite graphene is prepared by in-situ synthesis of Cu-MOF on the surface of modified graphene; through amidation reaction of polybenzimidazole and p-aminobenzoic acid on the surfaces of the graphene oxide nanosheets, the heat resistance and mechanical properties of the binder are improved, and the bonding effect of the binder on the graphene oxide nanosheets is improved by synthesizing a porous structure on the surfaces of the graphene oxide nanosheets. And shedding of the graphene nanosheets caused by high temperature and electrolyte is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of electrode materials, and in particular relates to a pole piece slurry for a high-capacity lithium battery for unmanned aerial vehicles and a coating process thereof. Background Art

[0002] Lithium-ion batteries, with their excellent rechargeability, high power density, and high energy density, are widely used in daily life. They have rapidly evolved from the preferred power source for relatively small applications such as portable electronic devices to large-scale applications such as drones, hybrid electric vehicles, and even stationary energy storage systems. Graphite, as an inexpensive, readily available, highly conductive non-metallic material, has a wide range of applications. Graphite's stable structure, low voltage plateau, and strong ability to intercalate and deintercalate lithium ions make it an ideal negative electrode material for lithium-ion batteries.

[0003] Since graphite is not compatible with some electrolytes, during the charge and discharge process of lithium-ion batteries with graphite as the negative electrode, organic solvents will react with Li + They are inserted into the graphite layers together, causing the graphite sheets to fall off, affecting the capacity of the battery. When the temperature is high, the adhesive of the graphite pole piece will reduce the bonding strength, causing the graphite sheet to fall off further. A heat-resistant adhesive is needed, usually a fluorine-containing adhesive such as polytetrafluoroethylene. However, fluorine-based polymers have serious impacts on human health and the environment during the entire production, manufacturing and disposal process. In the field of drone applications, due to the high energy consumption of drones, rapid discharge will cause the battery temperature to rise rapidly, and rapid charging will also cause a large amount of heat to accumulate, resulting in a decrease in battery life and capacity.

[0004] Chinese invention patent application publication number CN111653831A discloses a method for preparing a high-safety, high-temperature, long-life aqueous lithium iron phosphate battery. Graphene conductive slurry is applied to the surfaces of the positive and negative electrode sheets, and together with a microporous membrane containing an adhesive layer, a battery cell is formed in a stacked manner. The battery is then hot-pressed, welded, glued, and encapsulated with an aluminum-plastic film to obtain a battery with the characteristics of high temperature resistance and slow cycle capacity decay. However, this solution uses lithium iron phosphate as the conductive material, which has weak conductivity and low theoretical capacity. In addition, the resulting battery is heavy, making it unsuitable for the field of lithium batteries for drones. Summary of the Invention

[0005] The purpose of the present invention is to solve the problem that the heat resistance of fluorine-free binders is low, which causes graphite pole pieces to easily fall off at high temperatures and leads to a decrease in battery capacity, and to provide a pole piece slurry for high-capacity lithium batteries for drones and its coating process.

[0006] The present invention improves the heat resistance and mechanical properties of the binder through the amidation reaction of polybenzimidazole and p-aminobenzoic acid on the surface of graphene oxide nanosheets, and increases the bonding effect of the binder on the graphene oxide nanosheets by synthesizing a porous structure on the surface of the graphene oxide nanosheets, thereby reducing the shedding of the graphene nanosheets caused by high temperature and electrolyte.

[0007] The purpose of the present invention can be achieved through the following technical solutions:

[0008] A pole piece slurry for a high-capacity lithium battery for drones, the pole piece slurry comprising the following components in parts by mass:

[0009] 5-8 parts of polybenzimidazole, 40-50 parts of dimethylacetamide, 15-20 parts of supported MOF composite graphene, 3-4 parts of carbon nanotubes and 5-10 parts of conductive carbon black.

[0010] Furthermore, the loaded MOF composite graphene is prepared by adsorbing loaded p-aminobenzoic acid on the MOF composite graphene.

[0011] Furthermore, MOF composite graphene is prepared by in situ synthesis of Cu-MOF on the surface of modified graphene.

[0012] Furthermore, the modified graphene is prepared by modifying graphene oxide nanosheets with p-phenylenediamine.

[0013] Furthermore, the MOF-loaded composite graphene is specifically prepared by the following steps:

[0014] The MOF composite graphene was ultrasonically dispersed in ethanol in a reactor, p-aminobenzoic acid was added, the temperature was raised to 40-50° C. and the reaction was carried out for 1-2 hours. The precipitate was collected by filtration and vacuum dried to obtain the loaded MOF composite graphene.

[0015] Furthermore, the usage ratio of MOF composite graphene, ethanol and p-aminobenzoic acid is 15-20 g: 800-1000 mL: 4-5 g.

[0016] Furthermore, MOF composite graphene is specifically prepared by the following steps:

[0017] Acetonitrile and deionized water are mixed in a reactor, and the sulfonated ligand is added. After stirring and dissolving, the modified graphene is added. After ultrasonic dispersion, the temperature is raised to 40-50°C and the reaction is carried out for 1-2 hours. Then, copper perchlorate is added, stirred and dissolved, and the temperature is raised to 120-130°C and the reaction is carried out for 20-24 hours. After cooling, the precipitate is collected by centrifugation, washed, and vacuum dried to obtain MOF composite graphene.

[0018] Furthermore, the usage ratio of acetonitrile, deionized water, sulfonated ligand, modified graphene and copper perchlorate is 400-500 mL: 400-500 mL: 4-6 g: 3-5 g: 6-8 g.

[0019] Further, the sulfonated ligand is prepared by the following steps:

[0020] Concentrated sulfuric acid and 4,4'-diphenyl ether dicarboxylic acid were mixed in a reaction kettle, heated to 100-110°C and reacted for 2-3 hours. After cooling, the mixture was poured into a saturated sodium chloride aqueous solution, filtered to obtain a precipitate, and the precipitate was vacuum dried at 110-120°C for 20-24 hours to obtain a sulfonated ligand.

[0021] Furthermore, the usage ratio of concentrated sulfuric acid to 4,4'-diphenyl ether dicarboxylic acid is 15-20 mL: 7-8 g.

[0022] Furthermore, the modified graphene is specifically prepared by the following steps:

[0023] In a reactor, graphene oxide nanosheets are ultrasonically dispersed in deionized water, p-phenylenediamine is dissolved in deionized water and added to the reactor, ultrasonically treated for 1-2 hours, heated to 70-80° C. and stirred for reaction for 20-24 hours, hydrazine monohydrate is added, heated to 80-90° C. and refluxed for reaction for 10-12 hours, centrifuged to obtain a precipitate, washed the precipitate, and vacuum dried to obtain modified graphene.

[0024] Furthermore, the usage ratio of graphene oxide nanosheets, deionized water, p-phenylenediamine and hydrazine monohydrate is 3-5 g: 4-5 g: 500-800 mL: 10-12 mL; the usage ratio of p-phenylenediamine and deionized water is 4-5 g: 500-800 mL.

[0025] A coating process for electrode slurry of a high-capacity lithium battery for drones comprises the following steps:

[0026] The high-capacity lithium battery pole piece slurry is stirred with a stirrer at 60-80 rpm and then evenly coated on the metal foil with an extrusion coater to form a pole roll. After coating, it is baked in an oven to remove the solvent at a baking temperature of 165-170 ° C. The baked pole roll is passed through a roller press at a pressure of 1.8-2.2 g / cm 3 Compact and roll to obtain the pole piece.

[0027] Beneficial effects of the present invention:

[0028] 1. The present invention uses polybenzimidazole as a binder and utilizes the amidation reaction between polybenzimidazole and p-aminobenzoic acid on the surface of graphene oxide nanosheets to improve the heat resistance and mechanical properties of the binder. By synthesizing a porous structure on the surface of the graphene oxide nanosheets, the adhesion of the binder to the graphene oxide nanosheets is increased, the shedding of the graphene nanosheets caused by high temperature and electrolyte is reduced, the cycle life of the lithium battery is increased, and the degree of battery capacity attenuation is reduced.

[0029] 2. The present invention prepares p-phenylenediamine-modified graphene by grafting p-phenylenediamine onto graphene oxide nanosheets and then reducing them with hydrazine hydrate. The p-phenylenediamine makes the modified graphene have good dispersibility and electrolyte wettability, effectively improves the compatibility of graphene with the electrolyte, and reduces the shedding of graphene.

[0030] 3. The amino groups on the surface of the modified graphene react with the sulfonic acid groups in the sulfonated ligands to graft, so that the sulfonated ligands are grafted and fixed on the surface of the modified graphene. Then, through thermal reaction with copper salt, Cu-MOF is in situ synthesized on the surface of the modified graphene with the sulfonated ligands as sites. The p-phenylenediamine modification improves the dispersion between the graphene oxide nanosheets. Cu-MOF forms gaps between the modified graphene, preventing the agglomeration of the modified graphene, prompting the modified graphene to form a more uniform conductive network, and improving the conductivity. DETAILED DESCRIPTION

[0031] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0032] Example 1: A high-capacity lithium battery electrode slurry for drones, comprising the following steps:

[0033] S1. Ultrasonic dispersion of 3 g of graphene oxide nanosheets in 500 mL of deionized water was performed in a reactor. 4 g of p-phenylenediamine was dissolved in 500 mL of deionized water and added to the reactor. The mixture was ultrasonically treated for 1 h. The mixture was heated to 70°C and stirred for 20 h. 10 mL of hydrazine monohydrate was added and the mixture was heated to 80°C and refluxed for 10 h. The mixture was centrifuged to obtain a precipitate. The precipitate was washed with deionized water and vacuum dried at 50°C for 20 h to obtain modified graphene.

[0034] S2. In a reaction kettle, 15 mL of concentrated sulfuric acid and 7 g of 4,4'-diphenyl ether dicarboxylic acid were mixed, the temperature was raised to 100°C, and the mixture was reacted for 2 h. After cooling, the mixture was poured into a saturated aqueous sodium chloride solution, filtered to obtain a precipitate, and the precipitate was vacuum-dried at 110°C for 20 h to obtain a sulfonated ligand.

[0035] S3. Mix 400 mL of acetonitrile and 400 mL of deionized water in a reactor, add 4 g of sulfonated ligand, stir to dissolve, then add 3 g of modified graphene, ultrasonically disperse, heat to 40 ° C and react for 1 hour, then add 6 g of copper perchlorate, stir to dissolve, heat to 120 ° C and react for 20 hours, cool and collect the precipitate by centrifugation, wash the precipitate with deionized water, and vacuum dry at 50 ° C for 20 hours to obtain MOF composite graphene.

[0036] S4. Ultrasonic dispersion of 15 g of MOF composite graphene in 800 mL of ethanol was performed in a reactor. 4 g of p-aminobenzoic acid was added. The temperature was raised to 40° C. for reaction for 1 h. The precipitate was collected by filtration and vacuum dried at 50° C. for 10 h to obtain the loaded MOF composite graphene.

[0037] S5. Dissolve 5 g of polybenzimidazole in 40 mL of dimethylacetamide in a reactor, heat to 120°C, stir and dissolve, cool, add 15 g of loaded MOF composite graphene, 3 g of carbon nanotubes and 5 g of conductive carbon black, ultrasonically disperse and stir overnight to obtain a high-capacity lithium battery electrode slurry.

[0038] A coating process for electrode slurry of a high-capacity lithium battery for drones comprises the following steps:

[0039] The high-capacity lithium battery pole piece slurry was stirred with a stirrer at 60 rpm and then evenly coated on the metal foil with an extrusion coater to form a pole roll. After coating, the pole roll was baked in an oven to remove the solvent at a baking temperature of 165 ° C. The baked pole roll was passed through a roller press at a pressure of 1.8 g / cm 3 Compact and roll to obtain the pole piece.

[0040] Example 2: A high-capacity lithium battery electrode slurry for drones, comprising the following steps:

[0041] S1. Ultrasonic dispersion of 4 g of graphene oxide nanosheets in 650 mL of deionized water was performed in a reactor. 4.5 g of p-phenylenediamine was dissolved in 650 mL of deionized water and added to the reactor. The mixture was ultrasonically treated for 1.5 h. The mixture was heated to 75 °C and stirred for 22 h. 11 mL of hydrazine monohydrate was added and the mixture was heated to 85 °C and refluxed for 11 h. The precipitate was obtained by centrifugation and filtration. The precipitate was washed with deionized water and vacuum dried at 55 °C for 22 h to obtain modified graphene.

[0042] S2. In a reaction kettle, 17.5 mL of concentrated sulfuric acid and 7.5 g of 4,4'-diphenyl ether dicarboxylic acid were mixed, the temperature was raised to 105°C, and the mixture was reacted for 2.5 h. After cooling, the mixture was poured into a saturated aqueous sodium chloride solution, filtered to obtain a precipitate, and the precipitate was vacuum-dried at 115°C for 22 h to obtain a sulfonated ligand.

[0043] S3. Mix 450 mL of acetonitrile and 450 mL of deionized water in a reactor, add 5 g of sulfonated ligand, stir to dissolve, then add 4 g of modified graphene, ultrasonically disperse, heat to 45 ° C and react for 1.5 h, then add 7 g of copper perchlorate, stir to dissolve, heat to 125 ° C and react for 22 h, cool and centrifuge to collect the precipitate, wash the precipitate with deionized water, and vacuum dry at 55 ° C for 22 h to obtain MOF composite graphene.

[0044] S4. Ultrasonic dispersion of 17.5 g of MOF composite graphene in 900 mL of ethanol was performed in a reactor. 4.5 g of p-aminobenzoic acid was added. The temperature was raised to 45° C. for reaction for 1.5 h. The precipitate was collected by filtration and vacuum dried at 55° C. for 11 h to obtain the loaded MOF composite graphene.

[0045] S5. Dissolve 6 g of polybenzimidazole in 45 mL of dimethylacetamide in a reactor, heat to 125°C, stir and dissolve, cool, add 17.5 g of loaded MOF composite graphene, 3.5 g of carbon nanotubes and 7 g of conductive carbon black, ultrasonically disperse and stir overnight to obtain a high-capacity lithium battery electrode slurry.

[0046] A coating process for electrode slurry of a high-capacity lithium battery for drones comprises the following steps:

[0047] The high-capacity lithium battery pole piece slurry was stirred with a stirrer at 70 rpm and then evenly coated on the metal foil with an extrusion coater to form a pole roll. After coating, the pole roll was baked in an oven to remove the solvent at a baking temperature of 167 ° C. The baked pole roll was passed through a roller press at a pressure of 2 g / cm 3 Compact and roll to obtain the pole piece.

[0048] Example 3: A high-capacity lithium battery electrode slurry for drones, comprising the following steps:

[0049] S1. Ultrasonic dispersion of 5 g of graphene oxide nanosheets in 800 mL of deionized water was performed in a reactor. 5 g of p-phenylenediamine was dissolved in 800 mL of deionized water and added to the reactor. The mixture was ultrasonically treated for 2 h. The mixture was heated to 80 °C and stirred for 24 h. 12 mL of hydrazine monohydrate was added and the mixture was heated to 90 °C and refluxed for 12 h. The mixture was centrifuged to obtain a precipitate. The precipitate was washed with deionized water and vacuum dried at 60 °C for 24 h to obtain modified graphene.

[0050] Paraphenylenediamine was grafted onto graphene oxide nanosheets and then reduced with hydrazine hydrate to prepare paraphenylenediamine-modified graphene. Paraphenylenediamine gives the modified graphene good dispersibility and electrolyte wettability, effectively improving the compatibility of graphene with the electrolyte and reducing the shedding of graphene.

[0051] S2. In a reaction kettle, 20 mL of concentrated sulfuric acid and 8 g of 4,4'-diphenyl ether dicarboxylic acid were mixed, and the temperature was raised to 110°C for reaction for 3 h. After cooling, the mixture was poured into a saturated aqueous sodium chloride solution, filtered to obtain a precipitate, and the precipitate was vacuum dried at 120°C for 24 h to obtain a sulfonated ligand.

[0052] The sulfonated ligand containing a sulfonic acid group is prepared by sulfonating 4,4'-diphenyl ether dicarboxylic acid with concentrated sulfuric acid, so that the ligand contains a sulfonic acid group.

[0053] S3. Mix 500 mL of acetonitrile and 500 mL of deionized water in a reactor, add 6 g of sulfonated ligand, stir to dissolve, then add 5 g of modified graphene, ultrasonically disperse, heat to 50 ° C and react for 2 h, then add 8 g of copper perchlorate, stir to dissolve, heat to 130 ° C and react for 24 h, cool and collect the precipitate by centrifugation, wash the precipitate with deionized water, and vacuum dry at 60 ° C for 24 h to obtain MOF composite graphene.

[0054] The amino groups on the surface of the modified graphene react and graft with the sulfonic acid groups in the sulfonated ligand, so that the sulfonated ligand is grafted and fixed on the surface of the modified graphene. Then, through thermal reaction with copper salt, Cu-MOF is in situ synthesized on the surface of the modified graphene with the sulfonated ligand as the site. The modification with p-phenylenediamine improves the dispersion between the graphene oxide nanosheets. Cu-MOF forms gaps between the modified graphene, preventing the agglomeration of the modified graphene, prompting the modified graphene to form a more uniform conductive network, and improving the conductivity.

[0055] S4. Ultrasonic dispersion of 20 g of MOF composite graphene in 1000 mL of ethanol was performed in a reactor. 5 g of p-aminobenzoic acid was added. The temperature was raised to 50° C. for reaction for 2 h. The precipitate was collected by filtration and vacuum dried at 60° C. for 12 h to obtain the loaded MOF composite graphene.

[0056] By utilizing the reaction between the sulfonic acid group in the Cu-MOF ligand and the amino group on p-aminobenzoic acid and the adsorption capacity of Cu-MOF, p-aminobenzoic acid is adsorbed into the pores of Cu-MOF to obtain MOF composite graphene loaded with p-aminobenzoic acid.

[0057] S5. Dissolve 8 g of polybenzimidazole in 50 mL of dimethylacetamide in a reactor, heat to 130°C, stir and dissolve, cool, add 20 g of loaded MOF composite graphene, 4 g of carbon nanotubes and 10 g of conductive carbon black, ultrasonically disperse and stir overnight to obtain a high-capacity lithium battery electrode slurry.

[0058] Polybenzimidazole reacts with p-aminobenzoic acid to form polyamide groups. The polyamide groups improve the heat resistance and mechanical properties of the polybenzimidazole binder, reducing the impact of high temperature on lithium battery electrodes. In addition, since p-aminobenzoic acid is adsorbed by the MOF on the surface of the MOF composite graphene, the porous structure of the MOF increases the contact area, so that the polymer formed by polybenzimidazole and p-aminobenzoic acid firmly fixes the loaded MOF composite graphene, further reducing the shedding of graphene oxide nanosheets.

[0059] A coating process for electrode slurry of a high-capacity lithium battery for drones comprises the following steps:

[0060] The high-capacity lithium battery pole piece slurry was stirred with a stirrer at 80 rpm and then evenly coated on the metal foil with an extrusion coater to form a pole roll. After coating, the pole roll was baked in an oven to remove the solvent at a baking temperature of 170 ° C. The baked pole roll was passed through a roller press at a pressure of 2.2 g / cm 3 Compact and roll to obtain the pole piece.

[0061] Comparative Example 1: The difference from Example 1 is that in S2, the modified graphene is replaced by graphene oxide nanosheets of equal mass, and the other steps remain unchanged to prepare a high-capacity lithium battery electrode slurry.

[0062] Comparative Example 2: The difference from Example 1 is that in S3, the sulfonated ligand is replaced by an equal mass of 4,4'-diphenyl ether dicarboxylic acid, and the other steps remain unchanged to prepare a high-capacity lithium battery electrode slurry.

[0063] Comparative Example 3: The difference from Example 1 is that in S4, the MOF composite graphene is replaced by modified graphene of equal mass, and the other steps remain unchanged to prepare a high-capacity lithium battery electrode slurry.

[0064] Graphene oxide nanosheets with a particle size of 10-15 μm and a thickness of 6-8 nm were purchased from Jiangsu Pioneer Nanotechnology Co., Ltd.

[0065] The carbon nanotubes were multi-walled carbon nanotubes with a length of 10-30 μm and a diameter of 10-20 nm, purchased from Jiangsu Pioneer Nanotechnology Co., Ltd.

[0066] The electrode slurries of the lithium batteries prepared in Examples 1 to 3 and Comparative Examples 1 to 3 were coated on metal copper foil according to the coating process in Example 1 to obtain electrode sheets. The electrode sheets had a thickness of 0.1 mm and a diameter of 1.4 cm. The electrode sheets were assembled into button cells in a glove box. The positive electrode shell, metal lithium, diaphragm, electrode sheet, stainless steel gasket, spring sheet, and negative electrode shell were placed in this order. The electrolyte was 1 mol·L -1The button cell was tested with LiPF6 / DMC (dimethyl carbonate) / EC (ethylene carbonate) / DEC (ethyl methyl carbonate). The discharge capacity and capacity retention after 100 cycles of the button cell were tested. The button cell was placed in an oven at 80°C to test the discharge capacity and capacity retention after 100 cycles. The results are shown in Table 1:

[0067] Table 1: Button battery performance test results

[0068] project Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Discharge capacity (mAh / g) 235.2 242.5 248.7 221.4 226.4 216.3 Capacity retention rate (%) 231.6 238.9 245.2 208.3 214.1 201.5 Discharge capacity at high temperature (mAh / g) 214.3 218.1 223.4 188.2 195.6 174.3 Capacity retention rate at high temperature (%) 204.6 208.8 214.2 164.1 174.3 145.6

[0069] As can be seen from Table 1, the button battery made from the electrode piece prepared in the present invention has a high discharge capacity and a high capacity retention rate. It can still maintain a high discharge capacity at high temperature, and after cyclic discharge, the capacity retention rate is good, indicating that the electrode piece prepared after coating the electrode piece slurry prepared in the present invention has good high temperature resistance.

[0070] In Comparative Example 1, since the graphene oxide surface was not modified, the graphene oxide was easily agglomerated during the compounding process with MOF, resulting in a decrease in the loading amount of MOF on the graphene oxide surface and a decrease in the bonding effect of the polybenzimidazole binder.

[0071] In Comparative Example 2, since the MOF ligand was not sulfonated, the ligand was less grafted to the modified graphene surface, the synthesis uniformity of MOF on the modified graphene surface was reduced, and the adhesion effect of polybenzimidazole on the modified graphene was reduced.

[0072] In Comparative Example 3, since a porous MOF was not synthesized on the surface of graphene oxide, the bonding performance between the polyphenylene imidazole binder and graphene oxide was greatly weakened. In the electrode obtained by coating the prepared electrode slurry, the graphene oxide easily fell off at high temperature, resulting in a significant reduction in high-temperature discharge capacity.

[0073] While the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations can be made to the embodiments without departing from the principles and spirit of the invention.

Claims

1. A high-capacity lithium battery electrode slurry for drones, characterized in that: The electrode slurry comprises the following components in parts by mass: 5-8 parts of polybenzimidazole, 40-50 parts of dimethylacetamide, 15-20 parts of supported MOF composite graphene, 3-4 parts of carbon nanotubes and 5-10 parts of conductive carbon black; The loaded MOF composite graphene is prepared by adsorbing loaded p-aminobenzoic acid on the MOF composite graphene; The MOF composite graphene is prepared by in-situ synthesis of Cu-MOF on the surface of modified graphene; The modified graphene is prepared by modifying graphene oxide nanosheets with p-phenylenediamine.

2. The electrode slurry for a high-capacity lithium battery for a drone according to claim 1, characterized in that: The loaded MOF composite graphene is specifically prepared by the following steps: The MOF composite graphene was ultrasonically dispersed in ethanol in a reactor, p-aminobenzoic acid was added, the temperature was raised to 40-50° C. and the reaction was carried out for 1-2 hours. The precipitate was collected by filtration and vacuum dried to obtain the loaded MOF composite graphene.

3. The electrode slurry for a high-capacity lithium battery for a drone according to claim 2, characterized in that: The usage ratio of the MOF composite graphene, ethanol and p-aminobenzoic acid is 15-20 g: 800-1000 mL: 4-5 g.

4. The electrode slurry for a high-capacity lithium battery for a drone according to claim 3, characterized in that: The MOF composite graphene is specifically prepared by the following steps: Acetonitrile and deionized water are mixed in a reactor, and the sulfonated ligand is added. After stirring and dissolving, the modified graphene is added. After ultrasonic dispersion, the temperature is raised to 40-50°C and the reaction is carried out for 1-2 hours. Then, copper perchlorate is added, stirred and dissolved, and the temperature is raised to 120-130°C and the reaction is carried out for 20-24 hours. After cooling, the precipitate is collected by centrifugation, washed, and vacuum dried to obtain MOF composite graphene.

5. The electrode slurry for a high-capacity lithium battery for a drone according to claim 4, characterized in that: The usage ratio of the acetonitrile, deionized water, sulfonated ligand, modified graphene and copper perchlorate is 400-500 mL: 400-500 mL: 4-6 g: 3-5 g: 6-8 g.

6. The electrode slurry for a high-capacity lithium battery for a drone according to claim 5, characterized in that: The sulfonated ligand is prepared by the following steps: Concentrated sulfuric acid and 4,4'-diphenyl ether dicarboxylic acid were mixed in a reactor, heated to 100-110°C and reacted for 2-3 hours. After cooling, the mixture was poured into a saturated sodium chloride aqueous solution, filtered to obtain a precipitate, and the precipitate was vacuum dried at 110-120°C for 20-24 hours to obtain a sulfonated ligand.

7. The electrode slurry for a high-capacity lithium battery for a drone according to claim 6, characterized in that: The usage ratio of the concentrated sulfuric acid and 4,4'-diphenyl ether dicarboxylic acid is 15-20 mL: 7-8 g.

8. The electrode slurry for a high-capacity lithium battery for a drone according to claim 5, characterized in that: The modified graphene is specifically prepared by the following steps: In a reactor, graphene oxide nanosheets are ultrasonically dispersed in deionized water, p-phenylenediamine is dissolved in deionized water and added to the reactor, ultrasonically treated for 1-2 hours, heated to 70-80° C. and stirred for reaction for 20-24 hours, hydrazine monohydrate is added, heated to 80-90° C. and refluxed for reaction for 10-12 hours, centrifuged to obtain a precipitate, washed the precipitate, and vacuum dried to obtain modified graphene.

9. The electrode slurry for a high-capacity lithium battery for a drone according to claim 8, characterized in that: The usage ratio of the graphene oxide nanosheets, deionized water, p-phenylenediamine and hydrazine monohydrate is 3-5g:4-5g:500-800mL:10-12mL; the usage ratio of p-phenylenediamine and deionized water is 4-5g:500-800mL.

10. The coating process of the electrode slurry of a high-capacity lithium battery for drones according to any one of claims 1 to 9, characterized in that: The steps include: The high-capacity lithium battery pole piece slurry is stirred with a stirrer at 60-80 rpm and then evenly coated on the metal foil with an extrusion coater to form a pole roll. After coating, it is baked in an oven to remove the solvent at a baking temperature of 165-170 ° C. The baked pole roll is passed through a roller press at a pressure of 1.8-2.2 g / cm 3 Compact and roll to obtain the pole piece.