A method for recycling lithium battery negative electrodes to produce aluminum-ion battery positive electrode materials

Abstract

This invention discloses a method for producing aluminum-ion battery cathode materials from recycled lithium-ion battery anodes. The specific steps are as follows: Disassembling waste lithium-ion batteries in an argon-filled glove box. Separating the waste lithium-ion battery anode sheets obtained in the glove box and storing them in an anhydrous and oxygen-free glass bottle. Removing the glass bottle containing the waste anode sheets from the glove box, rapidly adding deionized water to the bottle, and sonicating for at least 1 hour to regenerate the waste graphite. The obtained recycled graphite is then heat-treated and acid-washed to obtain acid-treated recycled graphite nanosheets. Aminated recycled graphite nanosheets are then prepared using a diamine compound and the acid-treated recycled graphite nanosheets. This invention utilizes aminated recycled graphite nanosheets prepared from recycled graphite, achieving excellent electrochemical performance as a cathode material for aluminum-ion batteries. The preparation method is simple and easy to operate, uses readily available raw materials, and is suitable for large-scale production.

Description

Technical Field

[0001] This invention belongs to the fields of lithium battery waste graphite recycling and aluminum-ion battery, specifically relating to a method for recycling lithium battery negative electrodes to produce aluminum-ion battery positive electrode materials. Background Technology

[0002] During long-term cycling of lithium-ion batteries, the aging mechanism of the negative electrode is currently mainly considered to be the consumption of electrolyte and the thickening of the solid electrolyte interface on the graphite surface. The solid electrolyte interface forms in the early stages of cycling; it is an ionicly conductive but electronically insulating interface. Its outer layer contains loose organic oligomers, exhibiting insulating properties, while the dense inorganic lithium salt inner layer facilitates Li-ion exchange. + Through. During the long-term cycling process of lithium-ion batteries, the lithiation / delithiation process can cause cracks at the solid electrolyte interface, which leads to the thickening of the solid electrolyte interface, electrolyte consumption, and increased graphite surface defects during long-term cycling.

[0003] Waste lithium-ion batteries contain heavy metals such as lithium, nickel, cobalt, and manganese, as well as electrolytes that are harmful to the environment. Improper disposal of waste lithium-ion batteries can cause serious damage to land and water resources. Current research on waste lithium-ion battery recycling focuses primarily on valuable metals such as lithium, nickel, cobalt, aluminum, and copper in the cathode material, while waste anode graphite is often disposed of through landfill or incineration. These methods generate greenhouse gases and particulate pollutants, causing severe air pollution and harming human health. Chinese invention patent CN117673530A describes a method for preparing high-value-added graphene using ultrasonic exfoliation. This method utilizes the phenomenon of increased interlayer spacing caused by lithium ion insertion and extraction during long-term use of waste anode material. It combines wet and pyrometallurgical processes to recover waste graphite and then uses ball milling and ultrasonic methods to prepare graphene. Therefore, effectively implementing a 3R (reduce, reuse, recycle) system for waste lithium-ion battery graphite is essential. Previous reports have highlighted the extensive work done on recycling waste graphite from lithium-ion batteries, using the recycled graphite as a cathode material in lithium-ion batteries. Chinese invention patent CN117185289A pre-treats waste graphite using low-temperature calcination and acid treatment, then regenerates it using low-temperature catalytic graphitization for use as a cathode material in lithium-ion batteries. The performance of the recycled graphite is comparable to commercial graphite. However, no one has used recycled graphite in aluminum-ion batteries. Aluminum-ion batteries, as a strong competitor in future energy storage systems, possess a high theoretical specific capacity, with a theoretical volumetric specific capacity as high as 8046 mAh cm⁻¹. -3 and 2980mAh g -1Its specific capacity by weight ranks among the highest of all batteries. Currently, graphite-based cathode materials for aluminum-ion batteries have been criticized for their relatively low energy density compared to metal oxides, metal sulfides, and organic cathodes. Numerous studies have attempted to improve the energy density of graphite-based materials by preparing expanded graphite and graphene, or by using carbon nanotubes; however, the energy densities achieved by these materials are limited. Chinese invention patent CN113036122B employs a method for preparing expanded graphite, which possesses advantages such as low defect rate, high specific surface area, and good graphite sheet thickness. This expanded graphite is used as a cathode material for aluminum-ion batteries to achieve excellent electrochemical performance. This patent is the first to use recycled graphite to prepare aminated graphite nanosheets and use them as a cathode material for aluminum-ion batteries, achieving electrochemical performance exceeding that of most previously reported carbon-based cathode materials.

[0004] Currently, the recycling of waste lithium-ion battery graphite mostly employs wet or pyrometallurgical processes, using acidic or alkaline chemical reagents or thermal treatments, which are highly polluting, complex, and energy-intensive. The purpose of this invention is to address the shortcomings of existing technologies by employing an economical and environmentally friendly method for recycling graphite. This method is simple to operate and suitable for large-scale production. Graphite is recycled using water washing and ultrasonic methods to obtain micro-expanded layers of recycled graphite. This method for recycling waste graphite is clean, environmentally friendly, and cost-effective, making it suitable for industrial production. Simultaneously, aminated recycled graphite nanosheets were prepared using the recycled graphite. These aminated recycled graphite nanosheets exhibited excellent electrochemical performance as a cathode material for aluminum-ion batteries. The method used to prepare aminated graphite nanosheets is simple, the raw materials are readily available, and it is suitable for large-scale industrial production. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing technologies by providing a method for recycling lithium battery anodes to produce aluminum-ion battery cathode materials.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A method for recycling lithium battery negative electrodes to produce aluminum-ion battery positive electrode materials includes the following steps:

[0008] 1) Step 1: Place the waste lithium-ion battery in a glove box that is free of water and oxygen, and remove the negative electrode of the waste lithium-ion battery.

[0009] 2) Step 2: In the glove box, take an appropriate amount of the negative electrode sheet from step 1 above and add it into a glass bottle. After sealing, take out the glove box and quickly add deionized water into it for ultrasonication.

[0010] 3) Step 3: Separate the copper foil from the mixed solution in step 2, filter the residual powder in the solution, dry the filtered powder, and then sieve the dried powder.

[0011] 4) Step 4: The recovered graphite powder screened in Step 3 is chemically oxidized using sulfuric acid and nitric acid solutions, followed by rapid heat treatment at high temperature. It is then ultrasonically treated in acetone to obtain graphite nanosheets.

[0012] 5) Step 5: Further acidify the recovered graphite nanosheets obtained in step 4 with a mixture of concentrated sulfuric acid (98%) and concentrated nitric acid (68%), and then wash and dry at 80°C;

[0013] 6) Step 6: The acid-treated recovered graphite nanosheets from Step 5 are ultrasonically mixed with deionized water and a diamine compound. The mixture is then reacted under high temperature and nitrogen protection. The resulting aminated graphite nanosheets are then filtered, and the resulting solid powder is vacuum-dried at 60°C for 24 hours.

[0014] In step 1), the oxygen and water vapor content in the argon-filled glove box is less than 100 ppm.

[0015] In step 2), the deionized water has a TOC of 1.5 ppb, and the ultrasonic washing process takes 1-2 hours.

[0016] In step 3), the negative electrode sheet is placed in a glass bottle and sealed to ensure that the waste negative electrode sheet is in an anhydrous and oxygen-free environment, while ensuring that deionized water is added quickly within 1-2 seconds.

[0017] In step 3), a 200-400 mesh sieve is used to screen out any remaining small amounts of metal particles, such as those from the negative electrode current collector.

[0018] In step 4), the ratio of sulfuric acid to nitric acid is 2:1-3:1, the treatment time is 1-3 hours, the heat treatment temperature is 800-1000℃, the heat treatment time is 1-3 minutes, and the mixture is ultrasonically treated in acetone for 3-6 hours.

[0019] The ratio of sulfuric acid and nitric acid used in step 5) is 2:1-4:1, and the acid treatment time for graphite nanosheets is 1-3 hours.

[0020] Step 6) The acid treatment to recover graphite nanosheets is mixed with deionized water and diamino compound, and the ultrasonic treatment time is 10-30 min, the reaction temperature is 80-100℃, and the reaction time is 20-24 h.

[0021] Compared with the prior art, the present invention has the following advantages:

[0022] (1) This invention uses a water-washing ultrasonic process to recycle waste graphite. Compared with the current mainstream acid washing and heat treatment processes for recycling waste graphite, this process is environmentally friendly because it does not use acids or alkalis, and it is also inexpensive and simple because it does not require heat treatment. Thanks to these advantages, this process can be used for large-scale production, thereby achieving industrialization.

[0023] (2) The recycled graphite obtained in this invention retains the long-range ordered structure and slightly enlarged interlayer spacing of the original graphite. Taking advantage of these advantages, the recycled graphite is used directly as a cathode material for aluminum-ion batteries, which is rare for recycled graphite. Compared with commercial graphite, the recycled graphite exhibits better electrochemical performance.

[0024] (3) In this invention, recycled graphite is prepared into amino-based graphite nanosheets. Amino groups are introduced into the original structure to improve its electrochemical performance. When used as a cathode material for aluminum batteries, it achieves electrochemical performance exceeding that of most carbon-based materials. The preparation method has the advantages of simple operation and readily available raw materials, making it suitable for large-scale industrial production. Attached Figure Description

[0025] Figure 1 Cold field emission scanning electron microscope image of waste graphite prepared in Example 1.

[0026] Figure 2 The image is a cold field emission scanning electron microscope image of the recycled graphite prepared in Example 2.

[0027] Figure 3 The X-ray diffraction pattern of the waste graphite prepared in Example 1.

[0028] Figure 4 The X-ray diffraction pattern of the recycled graphite prepared in Example 2.

[0029] Figure 5 The Fourier transform infrared spectrum of the acid-treated graphite nanosheets prepared in Example 4 is shown.

[0030] Figure 6 The Fourier transform infrared spectrum of the amino-based graphite nanosheets prepared in Example 5 is shown.

[0031] Figure 7 Commercial graphite prepared in Example 3 at 100 mAg -1 Performance graph after 100 cycles at current density.

[0032] Figure 8 The recycled graphite prepared in Example 2 was at 100 mAg -1 Performance graph after 100 cycles at current density.

[0033] Figure 9The amino-based graphite nanosheets prepared in Example 5 were subjected to 100 mAg -1 Performance graph after 100 cycles at current density. Detailed Implementation

[0034] To make the technical features and advantages of the present invention clearer, a detailed description is provided below in conjunction with the accompanying drawings and specific embodiments.

[0035] All reagents used in the synthesis in the following examples are of analytical grade and have been strictly dehydrated. The main reagents will be briefly listed below.

[0036] Concentrated sulfuric acid (concentrated H2SO4, 98%): Sinopharm Chemical Reagent Co., Ltd., purity AR.

[0037] Concentrated nitric acid (concentrated HNO3, 68%): Sinopharm Chemical Reagent Co., Ltd., purity AR.

[0038] Polyvinylidene fluoride (PVDF): Sinopharm Chemical Reagent Co., Ltd., purity AR.

[0039] Acetone (AC): Sinopharm Chemical Reagent Co., Ltd., purity AR.

[0040] p-Phenylenediamine (PPD): Shanghai Aladdin Biochemical Technology Co., Ltd., purity AR.

[0041] Ferric chloride (FeCl3): Shanghai Aladdin Biochemical Technology Co., Ltd., purity AR.

[0042] N-Methylpyrrolidone (NMP): Shanghai Aladdin Biochemical Technology Co., Ltd., purity AR.

[0043] The anhydrous and oxygen-free environments in the following examples all refer to environments where O2 and H2O are less than 100 ppm.

[0044] To demonstrate the superior performance of the material obtained by the method of this invention, X-ray diffraction and field emission scanning electron microscopy tests were performed on the recycled graphite prepared by this invention and the raw material waste graphite. Constant current density charge-discharge cycle tests were conducted on the recycled graphite, commercial graphite, and aminated recycled graphite nanosheets prepared by this invention. Fourier transform infrared spectroscopy was performed on the acid-treated recycled graphite nanosheets and aminated recycled graphite nanosheets prepared by this invention. These tests characterize the advancement of the method of this invention and the superiority of the recycled graphite prepared by this invention as a cathode material for aluminum-ion batteries. Specific testing methods are as follows:

[0045] (1) X-ray diffraction test (XRD, Rigaku D / Max Ultima Ⅳ, Japan): The sample to be tested is ground into powder, added to the glass stage for testing, compacted and the excess powder around it is removed, and then placed in the instrument for testing. The measurement is carried out in the range of 10-80°, the scanning rate is 10° / min, and the data is processed by MDI Jade 6.

[0046] (2) Cold field emission scanning electron microscopy test (SEM, Hitachi S-4800, Japan): The prepared powder sample was dispersed on conductive adhesive with a toothpick, and gold was sprayed on the surface (40s). The cross-sectional morphology was then observed under a cold field emission scanning electron microscope.

[0047] (3) Fourier transform infrared spectroscopy (FTIR, Thermo Fisher Scientific Co., USA): After the prepared powder sample is completely dried, it is mixed with an appropriate amount of potassium bromide to prepare a transparent thin film for testing.

[0048] (4) Constant Current Density Charge-Discharge Cycle Test (GCD, Shenzhen NEWANE Electronics, China): The prepared powder sample was fabricated into aluminum-ion coin cells using steps 5 to 9 of Example 2 for testing. Test conditions: Voltage range 0.01-2.4V (vsAl / Al) 3+ The current density is 100 mAg. -1 100 charge / discharge cycles.

[0049] The embodiments of the present invention will be described in detail below with reference to the examples. Those skilled in the art will understand that the following examples are only preferred embodiments of the present invention in order to better understand the present invention, but the scope of protection of the present invention is not limited to the following examples.

[0050] Example 1

[0051] A method for recycling lithium battery negative electrodes to produce aluminum-ion battery positive electrode materials, comprising the following specific steps:

[0052] Step 1: Place the waste lithium-ion batteries to be recycled into a glove box (O2 and H2O < 100ppm), and disassemble them to remove the iron shell and explosion-proof rings and other protective components. Take out the battery cells, and separate the negative electrode (composed of current collector copper foil and waste graphite) from the positive electrode of the separator. Store the separated waste negative electrode in a sealed glass bottle.

[0053] 2) Step 2: Remove the above-mentioned waste negative electrode from the glove box and mechanically peel off the waste graphite from the negative electrode for subsequent field emission scanning electron microscopy and X-ray diffraction tests.

[0054] Example 2

[0055] A method for recycling lithium battery negative electrodes to produce aluminum-ion battery positive electrode materials, comprising the following specific steps:

[0056] Step 1: Place the waste lithium-ion batteries to be recycled into a glove box (O2 and H2O < 100ppm), and disassemble them to remove the iron shell and explosion-proof rings and other protective components. Take out the battery cells, and separate the negative electrode (composed of current collector copper foil and waste graphite) from the positive electrode of the separator. Store the separated waste negative electrode in a sealed glass bottle.

[0057] 2) Step 2: Take the glass bottle containing the waste negative electrode sheet (O2 and H2O <100ppm) out of the glove box, quickly add deionized water to cover the waste negative electrode sheet, and then perform ultrasonic treatment for 1.5h.

[0058] 3) Step 3: Separate the copper foil from the mixed solution in step 2, filter the residual powder in the solution, and dry the filtered powder at 80°C for 6 hours to obtain recycled graphite powder.

[0059] 4) Step 4: The dried recycled graphite powder is sieved through a 300-mesh sieve to remove small amounts of metal particles such as residual negative electrode current collector generated during the ultrasonic process. The sieved powder is then used for subsequent field emission scanning electron microscopy and X-ray diffraction tests, as well as the preparation of amino graphite nanosheets.

[0060] 5) Step 5: Mix the screened recycled graphite with acetylene black and polyvinylidene fluoride in a ratio of 8:1:1, and add an appropriate amount of N-methylpyrrolidone. Then, ball mill the mixture at 180 r / min for 6 hours.

[0061] 6) Step 6: After homogenization, use a frame coater to evenly spread the slurry on the copper foil with a thickness of 150μm. After it dries naturally until there is no obvious liquid, put it in a vacuum oven and dry at 105℃ for 12h.

[0062] 7) Step 7: The electrode sheet dried in step 6 is placed in the prepared high-concentration FeCl3 solution for etching for 3 hours. After all the copper foil is etched, the obtained recycled graphite film is washed 3 times with deionized water and then dried in a vacuum oven at 80°C for 6 hours.

[0063] 8) Step 8: Prepare 14mm circular sheets from the dried recycled graphite film in Step 7 using a cutting machine. Then, assemble the coin cell in a glove box in the following order: negative electrode shell, molybdenum foil, aluminum sheet, separator, recycled graphite film, molybdenum foil, gasket, and positive electrode shell, and add an appropriate amount of electrolyte. Then, seal the assembled battery using a hydraulic sealing machine.

[0064] 9) Step 9: After the sealed battery from step 8 has been left to stand for 24 hours, perform an electrochemical test.

[0065] Example 3

[0066] A method for recycling lithium battery negative electrodes to produce aluminum-ion battery positive electrode materials, comprising the following specific steps:

[0067] 1) Step 1: Prepare batteries using purchased commercial graphite powder and conduct comparative tests;

[0068] 2) The battery preparation process is the same as steps 5 to 9 in Example 2.

[0069] Example 4

[0070] A method for recycling lithium battery negative electrodes to produce aluminum-ion battery positive electrode materials, comprising the following specific steps:

[0071] 1) Step 1: The method for recycling and regenerating waste graphite is the same as steps 1 to 4 in Example 2;

[0072] 2) Step 2: The recycled graphite powder was chemically oxidized using a mixture of concentrated sulfuric acid (98%) and concentrated nitric acid (68%) in a 2:1 ratio, followed by rapid heat treatment at 1000℃ for 90 seconds. Graphite nanosheets were then obtained by ultrasonic treatment in acetone for 6 hours.

[0073] 3) Step 3: Add a mixed solution of concentrated sulfuric acid (98%) and concentrated nitric acid (68%) in a ratio of 3:1 to the recovered graphite nanosheets obtained in step 2 for further acidification. Stir for 3 hours, then wash and dry at 80°C to obtain acid-treated recovered graphite nanosheets.

[0074] Example 5

[0075] A method for recycling lithium battery negative electrodes to produce aluminum-ion battery positive electrode materials, comprising the following specific steps:

[0076] 1) Step 1: The method for recycling and regenerating waste graphite is the same as steps 1 to 4 in Example 2;

[0077] 2) Step 2: Acid-treated aminated graphite nanosheets are processed in the same way as steps 1 to 3 in Example 4;

[0078] 3) Step 3: The recovered graphite nanosheets treated with acid in Step 2 were mixed with deionized water and p-phenylenediamine (0.8 g of phenylenediamine was dissolved in 250 ml of deionized water, and then 8 g of graphite nanosheets were added), and sonicated for 30 min. Then the mixture was reacted at 90 °C under nitrogen protection for 24 h. The resulting aminated graphite nanosheets were then filtered, and the resulting solid powder was vacuum dried at 60 °C for 24 h.

[0079] 4) The battery preparation process is the same as steps 5 to 9 in Example 2.

[0080] See appendix Figure 1 and 2 These correspond to the cold field emission scanning electron microscope (CFET) results of waste graphite from lithium batteries and recycled graphite obtained by relevant methods in steps 1-4 of Examples 1 and 2, respectively. (See attached...) Figure 1 It can be observed that the waste graphite has become significantly granular after long-term use. The surface of the waste graphite is coated with an adhesive coating and a small amount of particles, which are composed of the solid electrolyte interface generated during long-term charge and discharge processes, as well as residual carbon black and binders. From the attached... Figure 2 It can be observed that after ultrasonic water washing and regeneration, the solid electrolyte interface and binder residues on the surface of the graphite have disappeared. This is because the hydrogen evolution process during ultrasonic water washing removes residual impurities from the surface. The recycled graphite exhibits good commercial potato morphology, indicating that the ultrasonic water washing process effectively removes surface waste and is considerably more advanced than existing recycling processes.

[0081] See appendix Figure 3 and 4 These correspond to the X-ray diffraction patterns of waste graphite from lithium batteries and recycled graphite obtained by relevant methods in steps 1-4 of Examples 1 and 2, respectively. (See attached...) Figure 3 It can be observed that in and attached Figure 4 Within the same peak intensity range, the diffraction corresponding to the (002) crystal plane of the waste lithium battery graphite is significantly weaker and contains impurity peaks, with the diffraction peak located at 26.55°. The weak diffraction peaks and the presence of impurity peaks are due to the presence of solid electrolyte interface and binder residues. Using Bragg's formula, the interlayer spacing of the graphite is calculated to be 0.335 nm. (From the attached...) Figure 4 It can be observed that after the ultrasonic washing process, the diffraction peaks corresponding to the (002) crystal plane of the recycled graphite are significantly enhanced and the impurity peaks disappear, indicating that the ultrasonic washing process effectively removes impurities. Simultaneously, the diffraction peak corresponding to the (002) crystal plane shifts to the left to 26.34°. Calculations using Bragg's formula show that the interlayer spacing of the graphite increased to 0.338 nm after ultrasonic washing. This indicates that the ultrasonic washing process not only removes residual impurities but also effectively expands the interlayer spacing of the recycled graphite.

[0082] See appendix Figure 5 and 6 The Fourier transform infrared spectra are respectively those of the acid-treated and aminated recovered graphite nanosheets prepared by relevant methods in steps 1-3 of Examples 4 and 5. (From the appendix...) Figure 5 It can be observed at 1732, 1620, 1220 and 1050 cm.-1 Peaks were observed at nearby locations, attributed to the stretching vibrations of C=O in carboxyl or carbonyl groups, the stretching vibrations of C=C in aromatic groups, the stretching vibrations of CO in epoxide groups, and the stretching vibrations of CO in alkoxide groups, respectively. Peaks were observed at 3385 and 1407 cm⁻¹. -1 The characteristic absorption peaks at the left and right positions represent the stretching and bending vibrations of hydroxyl groups, respectively, indicating that oxygen-containing groups were introduced into the recycled graphite nanosheets after acid treatment. (From the attached...) Figure 6 It can be observed that all these absorption peaks corresponding to the oxygen-containing functional groups in the acid-treated graphite nanosheets almost disappear, proving that the oxygen-containing functional groups in the acid-treated graphite nanosheets are well reduced after the reaction with p-phenylenediamine. Furthermore, at 1569 and 1508 cm⁻¹... -1 The novel peaks observed in the amino-based graphite nanosheets can be attributed to the in-plane bending vibrations of NH4+ and the oscillating vibrations of NH4+, respectively. Importantly, at 1169 cm⁻¹... -1 Another new peak was observed, corresponding to the stretching vibration of the CN bond, indicating the successful formation of C-NH-C bonds and demonstrating the successful preparation of aminated graphite nanosheets.

[0083] See appendix Figure 7 , 8 9 and 1 respectively correspond to the constant current density cycling curves of batteries assembled from recycled graphite, commercial graphite, and aminated graphite nanosheets obtained by relevant methods in Examples 2, 3, and 5, comparing the electrochemical performance of batteries assembled from recycled graphite, commercial graphite, and aminated graphite nanosheets. At 100 mAg... -1 A 100-cycle charge-discharge test was conducted at the specified current density, during which the recycled graphite exhibited a capacity of 106.4 mAh g. -1 The average specific capacity is much higher than 60.1 mAh g. -1 The average specific capacity indicates that the recycled graphite possesses better electrochemical performance. This demonstrates the superiority of the water washing recycling method and the advantage of the micro-expanded graphite obtained after recycling over commercial graphite. Meanwhile, amino-coated graphite nanoparticles (100 mAg) -1 The average specific capacity per 100 cycles at current density is 152.7 mAh g. -1 The average coulombic efficiency was 90.8%. Compared to virgin recycled graphite, the aminated recycled graphite nanosheets exhibited superior electrochemical performance. This is attributed to the excellent exfoliation properties of the aminated recycled graphite nanosheets and the influence of the -NH group in the introduced aniline group on the AlCl4 content during charge and discharge. - Adsorption and desorption behavior.

[0084] The above description is only a preferred embodiment of the present invention. All equivalent changes and modifications made within the scope of the claims of the present invention should be included in the scope of the present invention.

Claims

1. A method for recycling lithium battery negative electrodes to produce aluminum-ion battery positive electrode materials, characterized in that, The method comprises the following steps: Step 1): placing the waste lithium ion battery in an anhydrous and anaerobic glove box, and disassembling the negative plate of the waste lithium ion battery; Step 2): in the glove box, taking a proper amount of the negative plate in step 1) and adding it into a glass bottle, sealing the glass bottle, taking it out of the glove box, and quickly adding deionized water into the glass bottle and ultrasonic treatment; Step 3): separating the copper foil in the mixed solution in step 2), filtering the residual powder in the solution, and drying the filtered powder, and screening the dried powder to obtain graphite powder; Step 4): chemically oxidizing the recycled graphite powder screened in step 3) by using 98% concentrated sulfuric acid and 68% concentrated nitric acid solution, and quickly heat-treating at high temperature; ultrasonic treatment in acetone to obtain graphite nanosheets; Step 5): further acidifying the recycled graphite nanosheets obtained in step 4) with a mixture of 98% concentrated sulfuric acid and 68% concentrated nitric acid, and then washing and drying at 80°C to obtain acid-treated recycled graphene nanosheets; Step 6): ultrasonic mixing of the acid-treated recycled graphite nanosheets in step 5) with deionized water and a diamino compound; then reacting under the conditions of high temperature and nitrogen protection, and then suction filtering the obtained aminated graphite nanosheets, and vacuum drying the obtained solid powder at 60°C for 24h.

2. The method for producing a positive material of an aluminum-ion battery from a negative of a lithium battery according to claim 1, characterized in that: In step 1), the glove box is filled with inert gas, including argon or nitrogen.

3. The method for producing a positive material of an aluminum-ion battery from a negative of a lithium battery according to claim 1, characterized in that: In step 2), the ultrasonic treatment time of the deionized water is 1-3h.

4. The method for producing a positive material of an aluminum-ion battery from a negative of a lithium battery according to claim 1, characterized in that: In step 2), the negative plate is added into the glass bottle, and it is required to ensure that the waste negative plate is in an anhydrous and anaerobic environment.

5. The method for producing a positive material for an aluminum-ion battery from a negative of a lithium battery according to claim 1, characterized in that: In step 3), the screening uses a 200-400 mesh screen.

6. The method for producing a positive material for an aluminum-ion battery from a negative of a lithium battery according to claim 1, characterized in that: In step 4), the ratio of concentrated sulfuric acid and concentrated nitric acid is 2:1-3:1, and the chemical oxidation treatment time is 1-3h.

7. The method for producing a positive material for an aluminum-ion battery from a negative of a lithium battery according to claim 1, characterized in that: In step 4), the quick heat treatment time is 1-3min, the heat treatment temperature is 800-1000°C, and the ultrasonic treatment time in acetone is 3-6h.

8. The method for producing a positive material for an aluminum-ion battery from a negative of a lithium battery according to claim 1, characterized in that: In step 5), the acidification time of the acid-treated graphite nanosheets is 1-3h; the volume ratio of sulfuric acid to nitric acid in the mixed acid is 2:1-4:

1.

9. The method for producing a positive material for an aluminum-ion battery from a negative of a lithium battery according to claim 1, characterized in that: In step 6), the ultrasonic mixing time is 10-30min, the reaction temperature is 80-100°C, and the reaction time is 20-24h.

10. The method for producing a positive electrode material for an aluminum-ion battery from a negative electrode of a lithium battery according to claim 1, characterized by: In step 6), the diamino compound includes p-phenylenediamine, ethylenediamine, propylenediamine, and 2-methylpentanediamine.

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