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

Abstract

This invention discloses an electrode slurry for a high-capacity lithium battery for unmanned aerial vehicles and its coating process, belonging to the field of electrode material technology. By weight, it comprises the following raw materials: 5-8 parts polybenzimidazole, 40-50 parts dimethylacetamide, 15-20 parts supported MOF composite graphene, 3-4 parts carbon nanotubes, and 5-10 parts conductive carbon black. The supported MOF composite graphene is prepared by adsorbing and loading p-aminobenzoic acid onto MOF composite graphene. The MOF composite graphene is prepared by in-situ synthesis of Cu-MOF on the surface of modified graphene. This invention improves the heat resistance and mechanical properties of the binder through the amidation reaction of polybenzimidazole with p-aminobenzoic acid on the surface of graphene oxide nanosheets. It also increases the adhesion of the binder to the graphene oxide nanosheets by synthesizing a porous structure on the surface of the graphene oxide nanosheets, reducing the detachment of graphene nanosheets caused by high temperature and electrolyte.

Description

Technical Field

[0001] This invention belongs to the field of electrode material technology, specifically relating to an electrode slurry for high-capacity lithium batteries used in drones and its coating process. Background Technology

[0002] Lithium-ion batteries, with their excellent rechargeability, high power density, and high energy density, are widely used in daily life and have rapidly evolved from being 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 and readily available non-metallic material with high conductivity, has a wide range of applications. Graphite's stable structure, low voltage plateau, and strong ability to insert and extract lithium ions make it very suitable as the negative electrode material for lithium-ion batteries.

[0003] Because graphite has poor compatibility with some electrolytes, during the charging and discharging process of lithium-ion batteries using graphite as the negative electrode, organic solvents can react with Li... + The graphite sheets are inserted into the graphite layers together, causing them to detach and affecting the battery's capacity. Furthermore, at higher temperatures, the binder on the graphite electrodes weakens, leading to further detachment of the graphite sheets. Heat-resistant binders are required, typically fluorinated binders such as polytetrafluoroethylene (PTFE). However, fluorinated polymers have serious impacts on human health and the environment throughout the entire production, manufacturing, and disposal process. In the field of drone applications, due to the high energy consumption of drones, rapid discharge causes the battery temperature to rise rapidly, and rapid charging also leads to a large accumulation of heat, resulting in a decrease in battery life and capacity.

[0004] Chinese invention patent application CN111653831A discloses a method for preparing a high-safety, high-temperature, long-life aqueous lithium iron phosphate battery. The method involves coating graphene conductive paste onto the surfaces of positive and negative electrodes and stacking them together with a microporous membrane containing an adhesive layer to form a battery cell. The battery is then obtained through hot pressing, welding, adhesive bonding, and aluminum-plastic film encapsulation. It features high temperature resistance and slow cycle capacity decay. However, this method uses lithium iron phosphate as the conductive material, which has weak conductivity, low theoretical capacity, and a relatively large battery weight, making it unsuitable for lithium batteries used in drones. Summary of the Invention

[0005] The purpose of this invention is to solve the problem that the low heat resistance of fluorine-free binders leads to the easy detachment of graphite electrodes at high temperatures, resulting in a decrease in battery capacity. The invention provides an electrode slurry and its coating process for high-capacity lithium batteries for drones.

[0006] This invention improves the heat resistance and mechanical properties of the binder by amidation reaction of polybenzimidazole with p-aminobenzoic acid on the surface of graphene oxide nanosheets. By synthesizing a porous structure on the surface of graphene oxide nanosheets, the bonding effect of the binder on the graphene oxide nanosheets is increased, reducing the graphene nanosheets from falling off due to high temperature and electrolyte.

[0007] The objective of this invention can be achieved through the following technical solutions:

[0008] An electrode slurry for a high-capacity lithium battery for drones, the electrode slurry comprising the following raw materials by weight:

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

[0010] Furthermore, the supported MOF composite graphene is prepared by adsorbing and supporting p-aminobenzoic acid onto MOF composite graphene.

[0011] Furthermore, the 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 supported MOF composite graphene is prepared by the following steps:

[0014] MOF composite graphene was ultrasonically dispersed in ethanol in a reaction vessel, p-aminobenzoic acid was added, the temperature was raised to 40-50℃ and reacted for 1-2 hours, the precipitate was collected by filtration and vacuum dried to obtain supported MOF composite graphene.

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

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

[0017] Acetonitrile and deionized water were mixed in a reactor, sulfonated ligands were added, and after stirring to dissolve, modified graphene was added. After ultrasonic dispersion, the temperature was raised to 40-50℃ and reacted for 1-2 hours. Then, copper perchlorate was added, and after stirring to dissolve, the temperature was raised to 120-130℃ and reacted for 20-24 hours. After cooling, the precipitate was collected by centrifugation, washed, and vacuum dried to obtain MOF composite graphene.

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

[0019] Furthermore, 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 vessel and heated to 100-110℃ 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 dried under vacuum at 110-120℃ for 20-24 hours to obtain the sulfonated ligand.

[0021] Furthermore, the 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 prepared by the following steps:

[0023] In a reaction vessel, graphene oxide nanosheets were ultrasonically dispersed in deionized water. p-phenylenediamine was dissolved in deionized water and added to the reaction vessel. The mixture was ultrasonically treated for 1-2 hours, heated to 70-80℃ and stirred for 20-24 hours. Hydrazine monohydrate was added, and the mixture was refluxed at 80-90℃ for 10-12 hours. The precipitate was obtained by centrifugation and filtration. The precipitate was washed and vacuum dried to obtain modified graphene.

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

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

[0026] The electrode slurry for high-capacity lithium batteries is stirred evenly with a stirrer at 60-80 rpm, and then uniformly coated onto metal foil using an extrusion coating machine to form electrode rolls. After coating, the electrode rolls are baked in an oven at 165-170℃ to remove the solvent. The baked electrode rolls are then pressed using a roller press to achieve a thickness of 1.8-2.2 g / cm³. 3 The electrode is obtained by pressing with a compacting roller.

[0027] The beneficial effects of this invention are:

[0028] 1. This 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 graphene oxide nanosheets, the bonding effect of the binder on the graphene oxide nanosheets is increased, reducing the shedding of graphene nanosheets caused by high temperature and electrolyte, improving the cycle life of lithium batteries, and reducing the degree of battery capacity decay.

[0029] 2. This invention prepares p-phenylenediamine-modified graphene by grafting p-phenylenediamine onto graphene oxide nanosheets and then reducing them with hydrazine hydrate. p-phenylenediamine gives the modified graphene good dispersibility and electrolyte wettability, effectively improving the compatibility between graphene and electrolyte and reducing graphene shedding.

[0030] 3. The amino groups on the surface of modified graphene react with the sulfonic acid groups in the sulfonated ligands for grafting, fixing the sulfonated ligands on the surface of modified graphene. Then, through a thermal reaction with copper salt, Cu-MOF is synthesized in situ on the surface of modified graphene using the sulfonated ligands as sites. The modification with p-phenylenediamine improves the dispersibility between graphene oxide nanosheets. Cu-MOF forms spacers between the modified graphene, preventing the aggregation of modified graphene and promoting the formation of a more uniform conductive network, thus improving conductivity. Detailed Implementation

[0031] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments in the present invention. 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 of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

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

[0033] S1. In a reaction vessel, 3g of graphene oxide nanosheets were ultrasonically dispersed in 500mL of deionized water. 4g of p-phenylenediamine was dissolved in 500mL of deionized water and added to the reaction vessel. The mixture was ultrasonically treated for 1h, heated to 70℃ and stirred for 20h. 10mL of hydrazine monohydrate was added, and the mixture was refluxed at 80℃ for 10h. The precipitate was obtained by centrifugation and filtration. The precipitate was washed with deionized water and vacuum dried at 50℃ for 20h to obtain modified graphene.

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

[0035] S3. In a reaction vessel, 400 mL of acetonitrile and 400 mL of deionized water were mixed, 4 g of sulfonated ligand was added, and after stirring to dissolve, 3 g of modified graphene was added. After ultrasonic dispersion, the mixture was heated to 40 °C and reacted for 1 h. Then, 6 g of copper perchlorate was added, and after stirring to dissolve, the mixture was heated to 120 °C and reacted for 20 h. After cooling, the precipitate was collected by centrifugation, washed with deionized water, and dried under vacuum at 50 °C for 20 h to obtain MOF composite graphene.

[0036] S4. In a reaction vessel, 15g of MOF composite graphene was ultrasonically dispersed in 800mL of ethanol, 4g of p-aminobenzoic acid was added, the temperature was raised to 40℃ and reacted for 1h, the precipitate was collected by filtration, and the precipitate was dried under vacuum at 50℃ for 10h to obtain the supported MOF composite graphene.

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

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

[0039] The high-capacity lithium battery electrode slurry is stirred at 60 rpm to form a homogenized slurry, and then evenly coated onto metal foil using an extrusion coating machine to form an electrode roll. After coating, the electrode roll is baked in an oven at 165℃ to remove the solvent. The baked electrode roll is then pressed through a roller press to a pressure of 1.8 g / cm³. 3 The electrode is obtained by pressing with a compacting roller.

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

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

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

[0043] S3. In a reaction vessel, 450 mL of acetonitrile and 450 mL of deionized water were mixed, 5 g of sulfonated ligand was added, and after stirring to dissolve, 4 g of modified graphene was added. After ultrasonic dispersion, the mixture was heated to 45 °C and reacted for 1.5 h. Then, 7 g of copper perchlorate was added, and after stirring to dissolve, the mixture was heated to 125 °C and reacted for 22 h. After cooling, the precipitate was collected by centrifugation, washed with deionized water, and dried under vacuum at 55 °C for 22 h to obtain MOF composite graphene.

[0044] S4. In a reaction vessel, 17.5g of MOF composite graphene was ultrasonically dispersed in 900mL of ethanol, 4.5g of p-aminobenzoic acid was added, the temperature was raised to 45℃ and reacted for 1.5h, the precipitate was collected by filtration, and the precipitate was dried under vacuum at 55℃ for 11h to obtain supported MOF composite graphene.

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

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

[0047] The high-capacity lithium battery electrode slurry is stirred at 70 rpm to form a homogenized slurry, and then evenly coated onto metal foil using an extrusion coating machine to form an electrode roll. After coating, the electrode roll is baked in an oven at 167℃ to remove the solvent. The baked electrode roll is then pressed through a roller press at a ratio of 2 g / cm³. 3 The electrode is obtained by pressing with a compacting roller.

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

[0049] S1. In a reaction vessel, 5g of graphene oxide nanosheets were ultrasonically dispersed in 800mL of deionized water. 5g of p-phenylenediamine was dissolved in 800mL of deionized water and added to the reaction vessel. The mixture was ultrasonically treated for 2h, heated to 80℃ and stirred for 24h. 12mL of hydrazine monohydrate was added, and the mixture was refluxed at 90℃ for 12h. The precipitate was obtained by centrifugation and filtration. The precipitate was washed with deionized water and vacuum dried at 60℃ for 24h to obtain modified graphene.

[0050] p-Phenylenediamine was grafted onto graphene oxide nanosheets and then reduced with hydrazine hydrate to prepare p-Phenylenediamine-modified graphene. p-Phenylenediamine gave the modified graphene good dispersibility and electrolyte wettability, effectively improving the compatibility between graphene and electrolyte and reducing graphene shedding.

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

[0052] Sulfonated ligands containing sulfonic acid groups were prepared by sulfonating 4,4'-diphenyl ether dicarboxylic acid with concentrated sulfuric acid, thus making the ligands contain sulfonic acid groups.

[0053] S3. In a reaction vessel, 500 mL of acetonitrile and 500 mL of deionized water were mixed, 6 g of sulfonated ligand was added, and after stirring to dissolve, 5 g of modified graphene was added. After ultrasonic dispersion, the mixture was heated to 50 °C and reacted for 2 h. Then, 8 g of copper perchlorate was added, and after stirring to dissolve, the mixture was heated to 130 °C and reacted for 24 h. After cooling, the precipitate was collected by centrifugation, washed with deionized water, and dried under vacuum at 60 °C for 24 h to obtain MOF composite graphene.

[0054] The amino groups on the surface of modified graphene react with the sulfonic acid groups in the sulfonated ligands for grafting, fixing the sulfonated ligands on the surface of modified graphene. Then, through a thermal reaction with copper salt, Cu-MOF is synthesized in situ on the surface of modified graphene using the sulfonated ligands as sites. Modification with p-phenylenediamine improves the dispersibility between graphene oxide nanosheets. Cu-MOF forms spacers between modified graphene, preventing the aggregation of modified graphene and promoting the formation of a more uniform conductive network, thus improving conductivity.

[0055] S4. In a reaction vessel, 20g of MOF composite graphene was ultrasonically dispersed in 1000mL of ethanol, 5g of p-aminobenzoic acid was added, the temperature was raised to 50℃ and reacted for 2h, the precipitate was collected by filtration, and the precipitate was dried under vacuum at 60℃ for 12h to obtain the supported 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, as well as the adsorption capacity of Cu-MOF, p-aminobenzoic acid is adsorbed into the pores of Cu-MOF, thus obtaining MOF composite graphene loaded with p-aminobenzoic acid.

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

[0058] After polybenzimidazole reacts with p-aminobenzoic acid, it forms 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. Furthermore, since p-aminobenzoic acid is adsorbed by MOF on the surface of the MOF-loaded composite graphene, the porous structure of MOF increases the contact area, allowing the polymer formed by polybenzimidazole and p-aminobenzoic acid to firmly fix the MOF-loaded composite graphene, further reducing the shedding of graphene oxide nanosheets.

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

[0060] The high-capacity lithium battery electrode slurry is stirred at 80 rpm to form a homogenized slurry, and then evenly coated onto metal foil using an extrusion coating machine to form an electrode roll. After coating, the electrode roll is baked in an oven at 170℃ to remove the solvent. The baked electrode roll is then pressed through a roller press to a pressure of 2.2 g / cm³. 3 The electrode is obtained by pressing with a compacting roller.

[0061] Comparative Example 1: The difference from Example 1 is that in S2, the modified graphene is replaced with graphene oxide nanosheets of equal mass, while the other steps remain unchanged, to obtain the electrode slurry for high-capacity lithium batteries.

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

[0063] Comparative Example 3: The difference from Example 1 is that in S4, the MOF composite graphene is replaced with an equal mass of modified graphene, while the other steps remain unchanged, to obtain the electrode slurry for high-capacity lithium batteries.

[0064] The graphene oxide nanosheets had a particle size of 10-15 μm and a thickness of 6-8 nm, and were purchased from Jiangsu Xianfeng Nanotechnology Co., Ltd.

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

[0066] The electrode slurry of the lithium batteries prepared in Examples 1-3 and Comparative Examples 1-3 was coated onto copper foil using the coating process described 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 then used in a glove box for coin cell assembly, with the following order: positive electrode shell, lithium metal, separator, electrode sheet, stainless steel gasket, spring sheet, and negative electrode shell. The electrolyte was 1 mol·L⁻¹. -1The LiPF6 / DMC (dimethyl carbonate) / EC (ethylene carbonate) / DEC (ethyl methyl carbonate) compound was used to perform performance tests on coin cells. The discharge capacity and capacity retention after 100 cycles were tested. The coin cells were placed in an 80℃ oven to test the discharge capacity and capacity retention after 100 cycles. The results are shown in Table 1.

[0067] Table 1: Performance Test Results of Button Cells

[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 coin cells made from the electrode sheet prepared by the present invention have high discharge capacity and high capacity retention rate. They can still maintain a high discharge capacity at high temperatures, and the capacity retention rate is good after cycle discharge. This indicates that the electrode sheet prepared by the present invention after coating with electrode slurry has good high temperature resistance.

[0070] In Comparative Example 1, since the surface of graphene oxide was not modified, graphene oxide was prone to agglomeration during the composite process with MOF, resulting in a decrease in the loading of MOF on the surface of graphene oxide and a decrease in the adhesive effect of polybenzimidazole binder.

[0071] In Comparative Example 2, the lack of sulfonation of the MOF ligand resulted in fewer grafts between the ligand and the modified graphene surface, leading to a decrease in the uniformity of MOF synthesis on the modified graphene surface and a reduction in the adhesion of polybenzimidazole to the modified graphene.

[0072] In Comparative Example 3, the lack of a porous MOF structure on the surface of graphene oxide led to a significant reduction in the adhesion between the polyphenylene imidazole binder and graphene oxide. As a result, the graphene oxide in the electrode obtained by coating the electrode slurry was prone to detachment at high temperatures, leading to a significant reduction in high-temperature discharge capacity.

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

Claims

1. An electrode slurry for a high-capacity lithium battery for unmanned aerial vehicles, characterized in that, The electrode slurry, by weight, comprises the following raw materials: 5-8 parts polybenzimidazole, 40-50 parts dimethylacetamide, 15-20 parts supported MOF composite graphene, 3-4 parts carbon nanotubes and 5-10 parts conductive carbon black; The loaded MOF composite graphene was prepared by adsorbing and loading p-aminobenzoic acid onto MOF composite graphene. The MOF composite graphene was 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; The supported MOF composite graphene is prepared by the following steps: MOF composite graphene was ultrasonically dispersed in ethanol in a reaction vessel, p-aminobenzoic acid was added, the temperature was raised to 40-50℃ and reacted for 1-2 hours, the precipitate was collected by filtration and vacuum dried to obtain supported MOF composite graphene. The MOF composite graphene is specifically prepared by the following steps: Acetonitrile and deionized water were mixed in a reaction vessel, sulfonated ligands were added, and after stirring and dissolving, modified graphene was added. After ultrasonic dispersion, the temperature was raised to 40-50℃ and reacted for 1-2 hours. Then, copper perchlorate was added, and after stirring and dissolving, the temperature was raised to 120-130℃ and reacted for 20-24 hours. After cooling, the precipitate was collected by centrifugation, washed, and vacuum dried to obtain MOF composite graphene. The sulfonated ligand is prepared by the following steps: Concentrated sulfuric acid and 4,4'-diphenyl ether dicarboxylic acid were mixed in a reaction vessel and heated to 100-110℃ 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 dried under vacuum at 110-120℃ for 20-24 hours to obtain the sulfonated ligand.

2. The electrode slurry for a high-capacity lithium battery for unmanned aerial vehicles according to claim 1, characterized in that, The ratio of the amount of MOF composite graphene, ethanol and p-aminobenzoic acid is 15-20g: 800-1000mL: 4-5g.

3. The electrode slurry for a high-capacity lithium battery for unmanned aerial vehicles according to claim 1, characterized in that, The ratio of acetonitrile, deionized water, sulfonated ligand, modified graphene, and copper perchlorate is 400-500mL:400-500mL:4-6g:3-5g:6-8g.

4. The electrode slurry for a high-capacity lithium battery for unmanned aerial vehicles according to claim 1, characterized in that, The ratio of concentrated sulfuric acid to 4,4'-diphenyl ether dicarboxylic acid is 15-20 mL: 7-8 g.

5. The electrode slurry for a high-capacity lithium battery for unmanned aerial vehicles according to claim 1, characterized in that, The modified graphene is specifically prepared by the following steps: In a reaction vessel, graphene oxide nanosheets were ultrasonically dispersed in deionized water. p-phenylenediamine was dissolved in deionized water and added to the reaction vessel. The mixture was ultrasonically treated for 1-2 hours, heated to 70-80℃ and stirred for 20-24 hours. Hydrazine monohydrate was added, and the mixture was refluxed at 80-90℃ for 10-12 hours. The precipitate was obtained by centrifugation and filtration. The precipitate was washed and vacuum dried to obtain modified graphene.

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

7. The coating process for electrode slurry of a high-capacity lithium battery for unmanned aerial vehicles according to any one of claims 1-6, characterized in that, Includes the following steps: The electrode slurry for high-capacity lithium batteries is stirred evenly with a stirrer at 60-80 rpm, and then uniformly coated onto metal foil using an extrusion coating machine to form electrode rolls. After coating, the electrode rolls are baked in an oven at 165-170℃ to remove the solvent. The baked electrode rolls are then pressed using a roller press to achieve a thickness of 1.8-2.2 g / cm³. 3 The electrode is obtained by pressing with a compacting roller.