A flash repair and recycling process for the cathode material of lithium cobalt oxide batteries

Abstract

The present invention relates to a flash repair and recycling process for the cathode material of lithium cobalt oxide batteries, belonging to the technical field of battery materials. The present invention introduces a lithium source, a manganese source, and a nickel source. The introduction of the lithium source is to supplement the lithium that may be lost due to cyclic charge and discharge during battery use. The doping of manganese can improve its structural stability and introduce new electrochemically active sites; the doping of nickel can improve the energy density and rate performance of the lithium cobalt oxide material and increase the conductivity of the material. In the present invention, chitosan and polyvinyl alcohol are used in combination. Chitosan provides adhesiveness and stability, while PVA adjusts the viscosity and promotes dispersion. Under the combined action of the two, the added repair materials such as the lithium source, manganese source, and nickel source can better adhere to the surface of the cathode electrode sheet and improve its overall performance. In the present invention, graphene oxide is added to enhance the performance of the repaired cathode material. Graphene oxide can uniformly coat the surface of the lithium cobalt oxide cathode material to form a protective layer.

Description

Technical Field

[0001] The present invention belongs to the technical field of battery materials and relates to a flash repair and recycling process for the cathode material of lithium cobalt oxide batteries. Background Art

[0002] Lithium cobalt oxide is an important material and is widely used in fields such as lithium-ion batteries. With the popularization of electronic products and the rise of electric vehicles, the demand for lithium cobalt oxide is increasing continuously. However, due to its scarce resources and the risk of environmental pollution, the recycling of lithium cobalt oxide has become particularly important.

[0003] Currently, the recycling of lithium cobalt oxide that has received relatively much attention is mainly pyrometallurgy or hydrometallurgy. However, pyrometallurgy requires high-temperature treatment, has strict requirements for equipment, and has excessive energy consumption. Most hydrometallurgy processes use inorganic strong acids for leaching, and this process will release sulfur dioxide and harmful nitrogen-containing gases, which will pollute the environment. Summary of the Invention

[0004] The purpose of the present invention is to provide a flash repair and recycling process for the cathode material of lithium cobalt oxide batteries, which has the characteristics of stable performance.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] A flash repair and recycling process for the cathode material of lithium cobalt oxide batteries, and the specific process flow of the process is as follows.

[0007] S1: Immerse the lithium cobalt oxide battery in a phosphate solution, and consume the remaining power in the battery through the electrolysis process. The immersion time is 8 - 12 h.

[0008] S2: After the immersion is completed, wash with deionized water, disassemble the battery, and obtain the cathode plate of the lithium cobalt oxide battery.

[0009] S3: Immerse the cathode plate of lithium cobalt oxide in an organic solvent for 2 - 4 h. The solid-liquid ratio of the cathode plate of lithium cobalt oxide to the organic solvent is 1:(5 - 8) mg / ml to remove the binder on the surface, and then wash with an ethanol solution with a mass fraction of 30%. After the washing is completed, blow the surface of the cathode plate of the lithium cobalt oxide battery with nitrogen at 50 - 70 °C and a flow rate of 8 - 10 m / s for 1 - 2 h to obtain a dry cathode plate of the lithium cobalt oxide battery.

[0010] S4: Grind the dry cathode plate of the lithium cobalt oxide battery in a ball mill at a rotation speed of 400 r / min for 2 - 3 h to obtain a cathode plate powder of the lithium cobalt oxide battery with a particle size of 150 mesh. Then add 5 - 7 wt% of a lithium source, 3 - 5 wt% of a manganese source, and 2 - 3 wt% of a nickel source to the cathode plate powder of the lithium cobalt oxide battery, and continue to grind in the ball mill at a rotation speed of 500 r / min for 1 - 2 h to obtain a mixture A, and the particle size of the mixture A is 200 mesh.

[0011] S5: Mix chitosan and polyvinyl alcohol in a mass ratio of (1 - 3):1, dissolve them in a 5% acetic acid solution by mass, and prepare a mixed solution B with a mass fraction of 20 - 30%.

[0012] S6: Disperse mixture A in mixed solution B, and ultrasonicate for 0.5 - 2 h to prepare a solid - liquid mixture C with a solid - liquid ratio of 1:(5 - 10) mg / ml.

[0013] S7: Place the solid - liquid mixture C in liquid nitrogen and freeze for 10 - 15 min, then dry it at - 50 °C under vacuum for 2 - 4 h. Crush and grind the dried solid to obtain mixture D.

[0014] S8: Mix mixture D and graphene oxide in a mass ratio of (10 - 12):1, add 1 - 2 wt% of a dispersant, sinter at 300 - 350 °C for 1 - 2 h, and then crush to obtain the preliminarily repaired lithium cobalt oxide cathode powder.

[0015] S9: Conduct flash Joule heat treatment on the preliminarily repaired lithium cobalt oxide cathode powder to obtain the repaired lithium cobalt oxide cathode material.

[0016] Further, the phosphate in the phosphate solution in S1 is one or more of sodium phosphate, potassium phosphate, and magnesium phosphate.

[0017] Further, the concentration of the phosphate solution in S1 is 5 - 7 wt%.

[0018] Further, the voltage of the used lithium cobalt oxide battery after discharge in S1 is between 1.6 - 2.2 V.

[0019] Further, the organic solvent in S3 is one or more of N,N - dimethylformamide, N,N - dimethylacetamide, and dimethyl sulfoxide.

[0020] Further, the lithium source in S4 is one of lithium nitrate and lithium carbonate.

[0021] Further, the manganese source in S4 is one of manganese chloride, manganese carbonate, and manganese sulfate.

[0022] Further, the nickel source in S4 is one of nickel phosphate, nickel sulfate, and nickel carbonate.

[0023] Further, the dispersant in S8 is polyethylene glycol with a number - average molecular weight of 1000 - 2000.

[0024] Further, the parameters of the flash Joule heat treatment in S9 are a time of 15 - 30 s and a temperature of 1200 - 1800 °C.

[0025] The present invention immerses a lithium cobalt oxide battery in a phosphate solution, consumes the remaining power in the battery through the electrolysis process, ensures the efficiency and safety of the battery during subsequent processing, and the electrolysis process is mild and will not cause severe damage to the internal structure of the battery.

[0026] Wash the battery with deionized water, soak the lithium cobalt oxide positive electrode plate in an organic solvent after removing the surface impurities and residues to remove the binder on the surface, making the active substances easier to separate, wash with an ethanol solution and purge with nitrogen to further remove the residues and dry the electrode plate. After removing the binder, the purity of the active substances is higher, which is beneficial to subsequent processing; purging with nitrogen can quickly dry the electrode plate and avoid the performance degradation that may be caused by long-term high-temperature treatment.

[0027] Grind the dried lithium cobalt oxide battery positive electrode plate into powder to increase its specific surface area and improve the reaction activity; the grinding process can refine the particles and improve the uniformity of the material.

[0028] Put the solid-liquid mixture into liquid nitrogen for freezing, and then perform low-temperature drying under vacuum. This process can remove the solvent in the mixture while keeping its microstructure undamaged. The freeze-drying process can avoid the performance degradation and structural damage that may be caused by high-temperature treatment. Low-temperature drying can retain the original performance of the material and improve the repair effect. The addition of graphene oxide can enhance the conductivity and structural stability of the material.

[0029] Then promote the chemical reactions and interactions between the components through high-temperature sintering to form a stable repair layer. The flash Joule heat treatment process is fast and efficient, and can avoid the performance degradation that may be caused by long-term high-temperature treatment. The treated lithium cobalt oxide positive electrode material has better electrochemical performance and cycle stability.

[0030] The addition of the lithium source is mainly to supplement the lithium that may be lost during the charge and discharge cycles of the battery. As the positive electrode material of a lithium-ion battery, during the charge and discharge process, lithium ions will migrate between the positive and negative electrodes, and some lithium ions may not be completely intercalated back into the positive electrode material due to interfacial side reactions or material structure changes, resulting in a decline in material performance. The supplementation of the lithium source helps to restore the stoichiometric ratio of the material and improve its electrochemical performance. By supplementing the lithium source, the material structure changes caused by lithium loss can be reduced, thereby improving the cycle stability of the battery. The supplementation of the lithium source helps to restore the reversible capacity of the positive electrode material, enabling the battery to store more electrical energy.

[0031] The addition of manganese source is mainly to introduce manganese element. By doping manganese, the performance of lithium cobalt oxide material can be improved. Manganese doping can change the crystal structure of the material, enhance its structural stability, and introduce new electrochemically active sites. Manganese doping also helps to enhance the structural stability of lithium cobalt oxide material and reduce the structural changes during charge and discharge. In addition, the introduction of manganese can improve the cycling performance of the material, enabling the battery to still maintain good performance after multiple charge and discharges.

[0032] The addition of nickel source is mainly to introduce nickel element. By doping nickel, the energy density and rate performance of lithium cobalt oxide material can be improved. Nickel doping can increase the conductivity of the material and introduce more lithium storage sites. Nickel doping helps to improve the energy density of lithium cobalt oxide material, enabling the battery to store more electrical energy. The introduction of nickel can improve the rate performance of the material, enabling the battery to still maintain a high capacity and efficiency during rapid charge and discharge.

[0033] As a natural polymer material, chitosan has good biocompatibility, degradability and film-forming property. During the process of repairing lithium cobalt oxide cathode material, chitosan mainly acts as a binder and stabilizer, which helps to firmly attach the repair material to the surface of the cathode plate and improve its structural stability. Chitosan can enhance the adhesion between the repair material and the cathode plate, preventing detachment during subsequent processing. The film-forming property of chitosan helps to form a protective film on the surface of the cathode plate, improving the chemical stability and thermal stability of the material.

[0034] Polyvinyl alcohol (PVA) is a common water-soluble polymer material with good film-forming property and mechanical properties. During the repair process, PVA mainly acts as a thickening agent and dispersant, which helps to regulate the viscosity and stability of mixed solution B, enabling mixture A to be evenly dispersed in it. The addition of PVA can adjust the viscosity of mixed solution B, making it easier to operate and process. The dispersing effect of PVA helps mixture A to be evenly dispersed in mixed solution B, forming a stable solid-liquid mixture C.

[0035] Chitosan and polyvinyl alcohol can play a synergistic role when used in combination. Chitosan provides adhesiveness and stability, while PVA regulates viscosity and promotes dispersion. Under the combined action of the two, the added repair materials such as lithium source, manganese source, and nickel source can better adhere to the surface of the cathode plate and improve its overall performance. Then, through subsequent freeze-drying reaction, the repair materials are further fixed on the surface of the cathode plate. The combined use of chitosan and polyvinyl alcohol can significantly improve the effect of repairing lithium cobalt oxide cathode material, making the repaired cathode material significantly improved in terms of electrochemical performance, structural stability and cycle life.

[0036] In the present invention, graphene oxide is also added to improve the performance of the repaired cathode material. Graphene oxide can uniformly coat the surface of the lithium cobalt oxide cathode material to form a protective layer. This coating layer can not only prevent further damage to the cathode material during subsequent processing, but also improve the overall stability of the material. After coating on the surface of lithium cobalt oxide, it can significantly improve the conductivity of the cathode material, reduce the internal resistance of the battery, thereby improving the charge-discharge efficiency and cycle stability of the battery; under high voltage or high temperature conditions, the lithium cobalt oxide cathode material is prone to side reactions such as electrolyte decomposition and active material dissolution. The coating layer of graphene oxide can effectively inhibit the occurrence of these side reactions and protect the structural integrity of the cathode material; the coating layer of graphene oxide can reduce the direct contact between the active material and the electrolyte, reduce the probability of side reactions, and thus extend the service life of the battery; the conductivity of graphene oxide helps to improve the electron transport efficiency of the cathode material, enabling the battery to make more full use of the active material during the charge-discharge process, and further improving the energy density of the battery.

[0037] Advantages of the present invention:

[0038] (1) In the present invention, a lithium source, a manganese source, and a nickel source are introduced. The introduction of the lithium source is mainly to supplement the lithium that may be lost during the use of the battery due to cyclic charge and discharge; the performance of the lithium cobalt oxide material is improved by doping with manganese. The doping of manganese can change the crystal structure of the material, improve its structural stability, and introduce new electrochemically active sites; the energy density and rate performance of the lithium cobalt oxide material are improved by doping with nickel. The doping of nickel can increase the conductivity of the material and introduce more lithium storage sites. The doping of nickel helps to improve the energy density of the lithium cobalt oxide material, enabling the battery to store more electrical energy;

[0039] (2) In the present invention, chitosan and polyvinyl alcohol are used in combination. Chitosan provides adhesiveness and stability, while PVA adjusts the viscosity and promotes dispersion. Under the combined action of the two, the added repair materials such as the lithium source, manganese source, and nickel source can better adhere to the surface of the cathode plate and improve its overall performance, significantly improving the electrochemical performance, structural stability, and cycle life of the repaired cathode material;

[0040] (3) In the present invention, graphene oxide is added to improve the performance of the repaired cathode material. Graphene oxide can uniformly coat the surface of the lithium cobalt oxide cathode material to form a protective layer. This coating layer can not only prevent further damage to the cathode material during subsequent processing, but also improve the overall stability of the material. Specific embodiments

[0041] To further elaborate on the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following describes in detail the specific implementation manners, structures, features and their effects of the present invention in conjunction with embodiments.

[0042] Example 1

[0043] S1: Immerse the lithium cobalt oxide battery in a sodium phosphate solution with a concentration of 6 wt%, consume the remaining power in the battery through the electrolysis process, the immersion duration is 10 h, and the voltage of the used lithium cobalt oxide battery after discharging is 2.0 V.

[0044] S2: After the immersion is completed, wash with deionized water and disassemble the battery to obtain the positive electrode plate of the lithium cobalt oxide battery.

[0045] S3: Immerse the positive electrode plate of lithium cobalt oxide in N,N-dimethylformamide for 3 h, the solid-liquid ratio of the positive electrode plate of lithium cobalt oxide to N,N-dimethylformamide is 1:5 mg / ml, remove the binder on the surface, then wash with an ethanol solution with a mass fraction of 30%, and after the washing is completed, blow the surface of the positive electrode plate of the lithium cobalt oxide battery with nitrogen at 70 °C and a flow rate of 8 m / s for 1 h to obtain a dry positive electrode plate of the lithium cobalt oxide battery.

[0046] S4: Grind the dry positive electrode plate of the lithium cobalt oxide battery in a ball mill at a rotation speed of 400 r / min for 2 - 3 h to obtain a positive electrode plate powder of the lithium cobalt oxide battery with a particle size of 150 mesh. Then add 7 wt% lithium nitrate, 3 wt% manganese chloride, and 2 wt% nickel phosphate to the positive electrode plate powder of the lithium cobalt oxide battery, and continue to grind in the ball mill at a rotation speed of 500 r / min for 2 h to obtain mixture A, and the particle size of mixture A is 200 mesh.

[0047] S5: Mix chitosan and polyvinyl alcohol in a mass ratio of 2:1, dissolve them in an acetic acid solution with a mass fraction of 5% to prepare a mixed solution B with a mass fraction of 30%.

[0048] S6: Disperse mixture A in mixed solution B and ultrasonicate for 1 h to obtain a solid-liquid mixture C with a solid-liquid ratio of 1:7 mg / ml.

[0049] S7: Put solid-liquid mixture C into liquid nitrogen and freeze for 15 min, dry at -50 °C under vacuum for 4 h, crush and grind the dried solid to obtain mixture D.

[0050] S8: Mix mixture D and graphene oxide in a mass ratio of 10:1, then add 1 wt% polyethylene glycol 2000, sinter at 350 °C for 1 h, and crush to obtain the preliminarily repaired lithium cobalt oxide positive electrode powder.

[0051] S9: The preliminarily repaired lithium cobalt oxide cathode powder is subjected to flash Joule heat treatment with the parameters of 20 s for time and 1500 °C for temperature to obtain the repaired lithium cobalt oxide cathode material.

[0052] Example 2

[0053] S1: Immerse the lithium cobalt oxide battery in a potassium phosphate solution with a concentration of 5 wt%, consume the remaining power in the battery through the electrolysis process, with an immersion duration of 12 h. The voltage of the used lithium cobalt oxide battery after discharge is 2.2 V.

[0054] S2: After the immersion is completed, wash with deionized water, disassemble the battery to obtain the lithium cobalt oxide battery cathode plate.

[0055] S3: Immerse the lithium cobalt oxide cathode plate in N,N-dimethylacetamide for 2 h, with the solid-liquid ratio of the lithium cobalt oxide cathode plate to the organic solvent being 1:5 mg / ml to remove the surface binder, then wash with an ethanol solution with a mass fraction of 30%. After the washing is completed, purge the surface of the lithium cobalt oxide battery cathode plate with nitrogen at 50 °C and a flow rate of 10 m / s for 2 h to obtain a dry lithium cobalt oxide battery cathode plate.

[0056] S4: Grind the dry lithium cobalt oxide battery cathode plate in a ball mill at a rotation speed of 400 r / min for 2 - 3 h to obtain lithium cobalt oxide battery cathode plate powder with a particle size of 150 mesh. Then add 5 wt% lithium carbonate, 5 wt% manganese carbonate, and 3 wt% nickel sulfate to the lithium cobalt oxide battery cathode plate powder, and continue to grind in the ball mill at a rotation speed of 500 r / min for 1 h to obtain mixture A, with the particle size of mixture A being 200 mesh.

[0057] S5: Mix chitosan and polyvinyl alcohol in a mass ratio of 1:1 and dissolve them in an acetic acid solution with a mass fraction of 5% to prepare a mixed solution B with a mass fraction of 20%.

[0058] S6: Disperse mixture A in mixed solution B and ultrasonicate for 0.5 h to obtain a solid-liquid mixture C with a solid-liquid ratio of 1:5 mg / ml.

[0059] S7: Place solid-liquid mixture C in liquid nitrogen and freeze for 10 min, then dry at -50 °C under vacuum for 2 h. Grind the dried solid to obtain mixture D.

[0060] S8: Mix mixture D and graphene oxide in a mass ratio of 12:1, then add 2 wt% polyethylene glycol 1000, sinter at 300 °C for 2 h, and crush to obtain the preliminarily repaired lithium cobalt oxide cathode powder.

[0061] S9: Flash Joule heat treatment is performed on the preliminarily repaired lithium cobalt oxide cathode powder. The parameters of the flash Joule heat treatment are a time of 15 s and a temperature of 1800 °C, and the repaired lithium cobalt oxide cathode material is obtained.

[0062] Example 3

[0063] S1: Immerse the lithium cobalt oxide battery in a magnesium phosphate solution with a concentration of 7 wt%, consume the remaining power in the battery through the electrolysis process, and the immersion duration is 12 h. The voltage of the used lithium cobalt oxide battery after discharging is 1.6 V.

[0064] S2: After the immersion is completed, wash with deionized water and disassemble the battery to obtain the lithium cobalt oxide battery cathode plate.

[0065] S3: Immerse the lithium cobalt oxide cathode plate in dimethyl sulfoxide for 4 h. The solid-liquid ratio of the lithium cobalt oxide cathode plate to the organic solvent is 1:8 mg / ml to remove the surface binder, and then wash with an ethanol solution with a mass fraction of 30%. After the washing is completed, purge the surface of the lithium cobalt oxide battery cathode plate with nitrogen at 70 °C and a flow rate of 10 m / s for 2 h to obtain a dry lithium cobalt oxide battery cathode plate.

[0066] S4: Grind the dry lithium cobalt oxide battery cathode plate in a ball mill at a rotation speed of 400 r / min for 3 h to obtain lithium cobalt oxide battery cathode plate powder with a particle size of 150 mesh. Then add 7 wt% lithium nitrate, 3 wt% manganese sulfate, and 2 wt% nickel carbonate to the lithium cobalt oxide battery cathode plate powder, and continue to grind in the ball mill at a rotation speed of 500 r / min for 2 h to obtain mixture A, and the particle size of mixture A is 200 mesh.

[0067] S5: Mix chitosan and polyvinyl alcohol in a mass ratio of 3:1 and dissolve them in an acetic acid solution with a mass fraction of 5% to prepare a mixed solution B with a mass fraction of 30%.

[0068] S6: Disperse mixture A in mixed solution B and ultrasonicate for 2 h to prepare a solid-liquid mixture C with a solid-liquid ratio of 1:10 mg / ml.

[0069] S7: Freeze the solid-liquid mixture C in liquid nitrogen for 15 min and dry it at -50 °C under vacuum for 4 h. Grind the dried solid to obtain mixture D.

[0070] S8: Mix mixture D and graphene oxide in a mass ratio of 10:1, add 2 wt% polyethylene glycol 1000, sinter at 350 °C for 1 h, and crush to obtain the preliminarily repaired lithium cobalt oxide cathode powder.

[0071] S9: The preliminarily repaired lithium cobalt oxide cathode powder is subjected to flash Joule heat treatment with the parameters of 30 s for time and 1200 °C for temperature to obtain the repaired lithium cobalt oxide cathode material.

[0072] Comparative Example 1

[0073] In this comparative example, no manganese source is added, and the remaining steps are the same as those in Example 1.

[0074] Comparative Example 2

[0075] In this comparative example, no nickel source is added, and the remaining steps are the same as those in Example 1.

[0076] Comparative Example 3

[0077] In this comparative example, no chitosan and polyvinyl alcohol are added, and the remaining steps are the same as those in Example 1.

[0078] Comparative Example 4

[0079] In this comparative example, no graphene oxide is added, and the remaining steps are the same as those in Example 1.

[0080] The examples and comparative examples are detected. The discharge detection is carried out according to the standard GB / T 23365-2009, and the cycle retention rate test is carried out according to the standard GB / T 23366-2009. The experimental results are summarized in the following table.

[0081]

[0082] It can be seen from the experimental data that the introduction of manganese source, nickel source, chitosan, polyvinyl alcohol and graphene oxide improves the first-cycle discharge specific capacity and cycle retention rate of lithium cobalt oxide batteries.

[0083] The above is only a preferred embodiment of the present invention, and it does not impose any form of limitation on the present invention. Although the present invention has been disclosed above with the preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can make some changes or modifications to the equivalent embodiments with the equivalent changes within the scope of the technical solution of the present invention. However, as long as it does not depart from the content of the technical solution of the present invention, any brief modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A flash repair and recycling process for the cathode material of lithium cobalt oxide batteries, characterized in that, The specific process is as follows: S1: Immerse the lithium cobalt oxide battery in a phosphate solution, and consume the remaining power in the battery through the electrolysis process. The immersion time is 8 - 12 h. S2: After immersion, wash with deionized water, disassemble the battery to obtain the positive electrode plate of the lithium cobalt oxide battery. S3: Immerse the positive electrode plate of lithium cobalt oxide in an organic solvent for 2 - 4 h. The solid-liquid ratio of the positive electrode plate of lithium cobalt oxide to the organic solvent is 1:(5 - 8) mg / ml. Remove the binder on the surface, then wash with an ethanol solution with a mass fraction of 30%. After washing, blow the surface of the positive electrode plate of the lithium cobalt oxide battery with nitrogen at 50 - 70 °C and a flow rate of 8 - 10 m / s for 1 - 2 h to obtain a dry positive electrode plate of the lithium cobalt oxide battery. S4: Grind the dry positive electrode plate of the lithium cobalt oxide battery in a ball mill at a speed of 400 r / min for 2 - 3 h to obtain a positive electrode plate powder of the lithium cobalt oxide battery with a particle size of 150 mesh. Then add 5 - 7 wt% of a lithium source, 3 - 5 wt% of a manganese source, and 2 - 3 wt% of a nickel source to the positive electrode plate powder of the lithium cobalt oxide battery, and continue to grind in the ball mill at a speed of 500 r / min for 1 - 2 h to obtain mixture A. The particle size of mixture A is 200 mesh. S5: Mix chitosan and polyvinyl alcohol in a mass ratio of (1 - 3):1, and dissolve them in an acetic acid solution with a mass fraction of 5% to prepare a mixed solution B with a mass fraction of 20 - 30%. S6: Disperse mixture A in mixed solution B and ultrasonicate for 0.5 - 2 h to prepare a solid-liquid mixture C with a solid-liquid ratio of 1:(5 - 10) mg / ml. S7: Put solid-liquid mixture C into liquid nitrogen and freeze for 10 - 15 min, dry at -50 °C under vacuum for 2 - 4 h, and crush and grind the dried solid to obtain mixture D. S8: Mix mixture D and graphene oxide in a mass ratio of (10 - 12):1, add 1 - 2 wt% of a dispersant, sinter at 300 - 350 °C for 1 - 2 h, and crush to obtain the preliminarily repaired lithium cobalt oxide positive electrode powder. S9: Perform flash Joule heat treatment on the preliminarily repaired lithium cobalt oxide positive electrode powder to obtain the repaired lithium cobalt oxide positive electrode material.

2. The flash repair and recycling process for the cathode material of lithium cobalt oxide battery according to claim 1, characterized in that, The phosphate in the phosphate solution in S1 is one or more of sodium phosphate, potassium phosphate, and magnesium phosphate.

3. A flash repair and recycling process for the cathode material of a lithium cobalt oxide battery according to claim 1, characterized in that, The concentration of the phosphate solution in S1 is 5 - 7 wt%.

4. A flash repair and recycling process for the cathode material of a lithium cobalt oxide battery according to claim 1, characterized in that, The voltage of the used lithium cobalt oxide battery after discharge in S1 is between 1.6 - 2.2 V.

5. A flash repair and recycling process for the cathode material of a lithium cobalt oxide battery according to claim 1, characterized in that, The organic solvent in S3 is one or more of N,N-dimethylformamide, N,N-dimethylacetamide, and dimethyl sulfoxide.

6. A flash repair and recycling process for the cathode material of a lithium cobalt oxide battery according to claim 1, characterized in that, The lithium source in S4 is one of lithium nitrate and lithium carbonate.

7. A flash repair and recycling process for the cathode material of a lithium cobalt oxide battery according to claim 1, characterized in that, The manganese source in S4 is one of manganese chloride, manganese carbonate, and manganese sulfate.

8. A flash repair and recycling process for the cathode material of a lithium cobalt oxide battery according to claim 1, characterized in that, The nickel source in S4 is one of nickel phosphate, nickel sulfate, and nickel carbonate.

9. A flash repair and recycling process for the cathode material of a lithium cobalt oxide battery according to claim 1, characterized in that, The dispersant in S8 is polyethylene glycol with a number-average molecular weight of 1000 - 2000.

10. A flash repair and recycling process for the cathode material of a lithium cobalt oxide battery according to claim 1, characterized in that The parameters of the flash Joule heat treatment in S9 are a time of 15 - 30 s and a temperature of 1200 - 1800 °C.

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