Recycling method of waste lithium ion power battery negative electrode material

Abstract

The invention discloses a recycling method of a waste lithium-ion power battery negative electrode material, which comprises the following steps: deconstructing the waste battery negative electrode material through selective plasma electrolysis, separating organic matters and electrolyte to obtain untreated negative electrode powder, and drying the untreated negative electrode powder to obtain the waste lithium-ion power battery negative electrode material. The powder is refined into uniform particles by adopting a supercritical fluid cooling and crushing technology, the physical structure of the powder is kept, metal elements such as lithium, nickel and cobalt are extracted by utilizing a multi-frequency resonance auxiliary ion exchange technology, impurities are removed, further purification is performed by adopting a superconducting magnetic separation technology and a nanoscale aerosol separation technology, and a high-purity metal solution is generated; metal compounds are generated through an intelligent self-adaptive phase change precipitation technology and are reduced into recyclable metal materials through biological catalytic deposition, the whole recovery process is monitored and optimized through a closed-loop circulation intelligent feedback system, the metal recovery rate is maximized, and harmless treatment is ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of recycling and reusing waste lithium-ion power batteries, and in particular to a method for recycling negative electrode materials of waste lithium-ion power batteries. Background Art

[0002] With the widespread application of lithium-ion power batteries in new energy vehicles and energy storage equipment, the problem of recycling used batteries has become increasingly prominent. Although existing technologies can already realize the extraction and recycling of valuable metals in used lithium-ion batteries, there are still many deficiencies and defects in practical applications, resulting in low recycling efficiency, high energy consumption, and high environmental pollution risks, making it difficult to meet the needs of large-scale industrial applications.

[0003] Existing recycling technologies have obvious deficiencies in metal extraction efficiency. When traditional mechanical crushing technology is used for the initial processing of battery materials, due to the uneven powder particle size, some materials cannot fully contact the solution during the subsequent chemical leaching process, which in turn affects the metal extraction efficiency. Chemical leaching is the main method of metal extraction. Although it can extract metal elements such as lithium, nickel, and cobalt from battery materials, its selectivity is poor, especially when dealing with mixed materials of multiple metal elements. It is difficult to achieve accurate separation, and the extracted metal purity is low, which affects the subsequent refining and reuse. Due to unstable process conditions, the extraction rate is often difficult to improve, resulting in a large amount of resource waste.

[0004] Existing recycling technologies have high energy consumption, especially in thermal treatment processes, which often require high temperatures to decompose organic matter and electrolytes, consuming a lot of energy. High-energy consumption processes not only increase equipment operating costs, but also lead to a decrease in the economic benefits of the entire recycling process. The chemical leaching process requires a large amount of acid and alkali solutions, which react under high temperature conditions, further exacerbating energy consumption. For large-scale industrial recycling, energy consumption is a key challenge that cannot be ignored.

[0005] The risk of environmental pollution is another major drawback of existing technologies. The acid and alkali solutions used in chemical leaching usually contain a large amount of harmful substances. If they are not handled properly, they may have serious impacts on the environment. The treatment cost of heavy metal waste liquid is high, and if it is not treated thoroughly, it will pollute water sources and soil, threatening the ecosystem. The harmful gases produced by combustion in the traditional heat treatment process will also have an adverse effect on air quality if they are not effectively filtered and treated. Although waste gas treatment and waste liquid treatment systems have been introduced in some technologies, it is difficult to completely eliminate pollution due to the complexity of the treatment process itself.

[0006] The complexity of the process is also one of the bottlenecks of the existing technology. From the disassembly, crushing, leaching of waste batteries to the extraction and separation of metals, the entire recycling process requires multiple steps, and each step requires strict parameter control. If there is a fluctuation in process conditions or improper parameter control at any step, it will affect the results of subsequent steps. This multi-step process not only increases the difficulty of operation, but also significantly increases equipment investment and maintenance costs. The high requirements for operators also lead to an increase in human errors in the recycling process, affecting the stability of the process.

[0007] Insufficient resource utilization is another important issue. Existing chemical leaching and precipitation processes are often unable to effectively remove impurities after extracting metal elements, resulting in the recovered metal materials being of low purity and unable to be directly used in high-demand application scenarios. Chemical reagents used in large quantities are often difficult to recycle and reuse, which not only increases costs but also causes waste of resources. In many processes, the extracted metal materials still need to be purified multiple times, increasing the complexity and time cost of the entire recycling process.

[0008] The existing waste lithium-ion battery recycling process still lacks an intelligent control system. Most of the processes rely on fixed parameter settings, and operators manually monitor and adjust based on experience. It is difficult to ensure that the process conditions remain at the optimal state throughout the recycling process. Due to the lack of an intelligent feedback system, it is difficult to dynamically adjust according to real-time changes in process parameters. This not only affects the efficiency of the recycling process, but also easily leads to waste of resources, and it is impossible to maximize the metal recovery rate and resource utilization.

[0009] Therefore, how to provide a method for recycling and reusing the negative electrode materials of waste lithium-ion power batteries is an urgent problem to be solved by those skilled in the art. Summary of the invention

[0010] One purpose of the present invention is to propose a method for recycling and reusing the negative electrode materials of waste lithium-ion power batteries. The present invention makes full use of technologies such as selective plasma electrolysis, supercritical fluid cooling and crushing, multi-frequency resonance-assisted ion exchange, superconducting magnetic separation, nano-aerosol separation, intelligent adaptive phase change precipitation, and biocatalytic deposition, and describes in detail the whole process of extracting, separating and purifying metal elements such as lithium, nickel, and cobalt from battery materials. The method has the advantages of high metal recovery rate, low energy consumption, strong environmental protection, and excellent metal material recycling performance.

[0011] A method for recycling and reusing anode materials of waste lithium-ion power batteries according to an embodiment of the present invention comprises the following steps:

[0012] S1. Deconstructing waste lithium-ion batteries by selective plasma electrolysis to generate battery negative electrode materials, and separating organic matter and electrolyte in the negative electrode materials to obtain untreated negative electrode powder;

[0013] S2, cooling and crushing the obtained untreated negative electrode powder by supercritical fluid, refining the powder into uniform particles, while retaining the physical structure of the powder to form standardized particles;

[0014] S3. Using multi-frequency resonance-assisted selective ion exchange technology to process standardized particles, extract lithium, nickel, and cobalt metal elements from the particles, remove impurities, and generate a solution containing target metal elements and solid waste residue;

[0015] S4, performing superconducting magnetic separation on the solution containing the target metal element, further purifying the metal element by the magnetic field strength to generate a relatively pure metal solution, and removing the remaining trace impurities;

[0016] S5. Perform nano-aerosol separation on the relatively pure metal solution to further remove fine particle impurities in the solution and generate a metal solution with a purity of more than 99%;

[0017] S6. The high-purity metal solution after aerosol separation is precipitated by intelligent adaptive phase change precipitation technology to generate lithium, nickel, and cobalt metal compound precipitation, so that the metal elements are deposited in a form with a purity of more than 99.9%;

[0018] S7. converting the precipitated metal compound into a recyclable metal material through a biocatalytic deposition technique to form a metal product that can be used in secondary battery manufacturing;

[0019] S8. Use a closed-loop intelligent feedback system to monitor and optimize various parameters of the entire recycling process, use automated adjustment technology to maximize metal recovery rate and resource utilization, and make the entire process harmless.

[0020] Optionally, the S1 specifically includes:

[0021] S11, preliminarily dismantling the negative electrode material of the waste lithium-ion battery to obtain the negative electrode assembly;

[0022] S12, performing low temperature treatment on the negative electrode assembly, controlling the temperature at -20°C to 0°C to prevent damage to the material structure, and performing selective plasma electrolysis;

[0023] S13, plasma electrolysis using a composite electrolyte system, the electrolyte composition includes 0.1M to 1.0M lithium chloride, 0.05M to 0.5M sulfuric acid and 0.01M to 0.1M fluoride;

[0024] S14, controlling the electrolysis conditions, the current density is 0.5A / cm2 to 3A / cm2, the electrolysis time is 10 minutes to 60 minutes, the electrolysis temperature is controlled between 25°C and 45°C, and the pulse current mode is used to optimize the metal separation selectivity;

[0025] S15. During the electrolysis process, lithium cobalt oxide reacts with sulfuric acid, and the target metal elements lithium and cobalt are selectively separated through the reaction, and organic matter and electrolyte are removed;

[0026] S16. After the electrolysis process is completed, the untreated negative electrode powder is filtered out using a solid-liquid separation device, and the retention rate of the metal elements lithium and cobalt in the negative electrode powder is not less than 95%;

[0027] S17, subjecting the obtained negative electrode powder to airflow drying treatment, with the drying temperature controlled at 60° C. to 80° C. to make the particle size of the powder uniform.

[0028] Optionally, the S2 specifically includes:

[0029] S21, preliminarily screening the obtained negative electrode powder to screen out particles with a particle size greater than 50 microns to obtain uniform negative electrode powder;

[0030] S22, placing the screened uniform negative electrode powder in a supercritical fluid cooling and pulverizing device, using supercritical carbon dioxide as a cooling fluid medium;

[0031] S23, during the cooling and pulverizing process, the pressure of the supercritical fluid is controlled between 7.3 MPa and 10 MPa, and the temperature is controlled between 31° C. and 40° C., and the powder particles are refined to a particle size of 10 μm to 50 μm by cooling;

[0032] S24. During the supercritical cooling process, the pulverization effect is optimized by controlling the fluid physical state of the supercritical carbon dioxide:

[0033]

[0034] Where Z is the compression factor, T is the temperature, V m is the actual volume, V c is the critical volume, α is the temperature correction coefficient, T c is the critical temperature;

[0035] S25. By controlling pressure and temperature, the powder particle size is controlled within the target range to obtain standardized particles:

[0036]

[0037] Where d is the powder particle size, P is the pressure of the supercritical fluid, T is the temperature, and k and β are constants related to material properties.

[0038] Optionally, the S3 specifically includes:

[0039] S31, placing the obtained standardized particles in a multi-frequency resonance-assisted ion exchange device to prepare for extraction of lithium, nickel, and cobalt metal ions;

[0040] S32, adding a solution to the ion exchange device, wherein the solution components include 0.5M to 2.0M sulfuric acid and 0.1M to 0.5M lithium chloride, and the solution is used to optimize conductivity and extract lithium ions from the standardized particles;

[0041] S33, controlling the temperature of the solution between 50° C. and 80° C., adjusting the pH value of the solution to 1 to 2, and activating the multi-frequency resonance auxiliary system, controlling the vibration frequency between 10 Hz and 500 Hz, and the vibration amplitude between 0.1 mm and 5 mm, to optimize the metal ion exchange efficiency;

[0042] S34. With the assistance of multi-frequency resonance, the ion exchange reaction begins, and lithium, nickel, and cobalt metal elements are extracted from the standardized particles and enter the solution, while the solid residue is separated from the metal solution;

[0043] S35, calculate the lithium ion extraction rate R by the following formula Li :

[0044]

[0045] Among them, R Li is the extraction rate of lithium ions, is the concentration of lithium ions in the solution, is the initial concentration of lithium ions in the negative electrode material, f is the vibration frequency, A is the vibration amplitude, and α is the correction coefficient;

[0046] S36. After the ion exchange process is completed, use solid-liquid separation equipment to completely separate the lithium, nickel and cobalt metal ions in the solution from the solid residue, so that the purity of the extracted metal solution meets the requirements.

[0047] Optionally, the S4 specifically includes:

[0048] S41, placing a solution containing a target metal element in a superconducting magnetic separation device, and purifying the metal element by controlling the magnetic field strength;

[0049] S42, adjusting the magnetic field strength of the superconducting magnetic separation device to between 0.5 Tesla and 3 Tesla, and preferentially separating the magnetic metal elements through the high magnetic field strength, so that the magnetic metal elements are separated from the solution and enter the purification stage;

[0050] S43. Separate the magnetic metal ions by combining magnetic field strength, separation path, time and movement angle:

[0051]

[0052] Where v is the separation rate of metal ions, q is the charge of metal ions, B is the magnetic field strength, and B r is the reference magnetic field strength, m is the mass of the metal element, θ is the angle between the movement of the metal ions and the magnetic field direction, L is the separation path length, and t is the separation time;

[0053] Combining magnetic field strength and saturation magnetic field characteristics, the separation efficiency of metal ions is optimized:

[0054]

[0055] Where E is the separation efficiency, T is the total operation time, B sat is the saturation magnetic field strength, B r is the reference magnetic field strength, B is the actual magnetic field strength;

[0056] S44. For the weakly magnetic and non-magnetic metal elements in the remaining solution, gradually reduce the magnetic field strength to 0.5 Tesla to 1 Tesla, and effectively separate and purify the lithium ions by adjusting the magnetic field gradient;

[0057] S45. Through multi-level magnetic field control, the relatively pure metal solution is completely separated from the remaining trace impurities, so that the removal of impurities and the purity of the metal solution meet the predetermined requirements;

[0058] S46. Remove impurities and residues from the metal solution through solid-liquid separation equipment, and use the separated metal solution for metal recovery and reuse in the process.

[0059] Optionally, the S5 specifically includes:

[0060] S51, placing the obtained relatively pure metal solution in a nano-aerosol separation device, and using nano-aerosol separation technology to further remove fine particle impurities in the solution;

[0061] S52. In the aerosol separation device, the particle size range of the separated particles is controlled between 10 nanometers and 100 nanometers, and the purity of the metal solution is optimized by flow rate and pressure control;

[0062] S53, during the separation process, the removal efficiency of impurity particles E part To quantify:

[0063]

[0064] Among them, E part is the removal efficiency of impurity particles, d crit is the critical particle size for separation, dpart is the actual particle size of the impurity particles, P flow is the flow pressure of the aerosol separation equipment, P norm is standard pressure;

[0065] S54. By real-time monitoring of the particle size distribution of the metal solution, separation parameters are adjusted to maintain the stability and uniformity of the solution during the separation process, thereby generating a metal solution with a purity of more than 99%.

[0066] Optionally, the S6 specifically includes:

[0067] S61, placing the metal solution with a purity of more than 99% after aerosol separation in an intelligent adaptive phase change precipitation device, and generating lithium, nickel, and cobalt metal compound precipitates by intelligent adaptive phase change precipitation technology;

[0068] S62, intelligent adaptive control monitors the temperature, pH value and metal concentration in the metal solution in real time, dynamically adjusts the precipitation conditions according to the monitoring results, and causes the metal ions to undergo a phase change reaction;

[0069] S63, precipitation rate R of metal compound precip Perform the calculation:

[0070]

[0071] Among them, R precip is the precipitation rate, k is the rate constant, is the concentration of metal ions in the metal solution, T is the temperature, ΔG act is the activation free energy of the phase change reaction, R is the gas constant;

[0072] S64, dynamically adjusting the operating parameters in the precipitation process according to the temperature of 50° C. to 100° C. and the pH value of 1 to 3 fed back by the intelligent adaptive system, so as to promote the precipitation of lithium, nickel and cobalt metal compounds in the form of precipitation;

[0073] S65, monitoring the concentration of the metal solution in the range of 0.1M to 1.0M by the system in real time, and optimizing the precipitation efficiency to generate a metal compound with a purity of more than 99.9%;

[0074] S66. Separate the precipitated metal compounds from the solution using separation equipment to obtain lithium, nickel and cobalt metal compounds.

[0075] Optionally, the S7 specifically includes:

[0076] S71, subjecting the separated lithium, nickel and cobalt metal compounds to biocatalytic deposition, and reducing the metal compounds to reusable metal materials by a specific biocatalyst;

[0077] S72. Use a specific biocatalyst with a concentration of 0.1 mg / L to 10 mg / L to regulate the metal deposition rate R dep :

[0078]

[0079] Among them, R dep is the metal deposition rate, is the concentration of metal ions in the solution, k bio is the activity constant of the biocatalyst, T is the reaction temperature, ΔE bio is the activation energy of the biocatalytic process, R is the gas constant;

[0080] S73. According to the activity and concentration of the catalyst, the deposition time is controlled between 1 hour and 10 hours to achieve stability of the deposition process and optimize the recycling performance of the metal material;

[0081] S74, when the deposition is completed, separating the deposited metal material from the solution by a solid-liquid separation device;

[0082] S75. Post-process the deposited metal material to make it suitable for secondary battery manufacturing and ensure that the mechanical and electrochemical properties of the metal material meet the requirements for reuse.

[0083] Optionally, the S8 specifically includes:

[0084] S81. Monitor the temperature, pressure and material separation during the recovery process in real time and adjust the process conditions of metal extraction, separation and precipitation;

[0085] S82, according to temperature feedback, controlling the temperature during the recovery process between 50°C and 100°C, adjusting the operating conditions during the metal extraction and precipitation process, and adjusting the metal recovery rate;

[0086] S83. Through pressure monitoring, dynamically adjust the pressure during the recovery process to optimize the efficiency of metal ion separation and purification:

[0087]

[0088] Among them, P opt is the optimized pressure, P init is the initial pressure, V sys is the system volume, R is the gas constant, T is the system temperature, is the concentration of metal ions after separation, is the initial metal ion concentration;

[0089] S84. Real-time monitoring of material separation, and adjustment of flow and pressure in the process based on feedback of separation efficiency and metal purity:

[0090]

[0091] Among them, F opt is the optimized flow rate, k is the flow constant, is the final metal concentration, T is the temperature, t is the separation time, ΔE is the activation energy of the separation process, and R is the gas constant;

[0092] S85. According to the parameters fed back during the material separation and purification process, adjust the process steps to maximize the metal recovery rate, control energy consumption and resource utilization, and make the entire process harmless.

[0093] The beneficial effects of the present invention are:

[0094] The present invention realizes efficient recovery of valuable metal elements such as lithium, nickel, and cobalt in the negative electrode materials of waste lithium-ion power batteries by comprehensively utilizing advanced technologies such as selective plasma electrolysis, supercritical fluid cooling and crushing, multi-frequency resonance-assisted ion exchange, superconducting magnetic separation, nano-aerosol separation, intelligent adaptive phase change precipitation, and biocatalytic deposition. Compared with the prior art, the present invention has significant advantages in metal extraction efficiency, energy consumption control, environmental protection, and resource utilization. The selective plasma electrolysis technology can deconstruct the negative electrode materials of the battery at a relatively low temperature, effectively reducing energy consumption while improving the efficiency of metal extraction; the supercritical fluid cooling and crushing technology retains the physical structure of the powder, further optimizing the effects of subsequent ion exchange and metal extraction processes. Through the multi-frequency resonance-assisted ion exchange technology, the present invention improves the extraction rate of lithium, nickel, and cobalt metal ions and effectively separates impurities.

[0095] In the purification process of the metal solution of the present invention, superconducting magnetic separation and nano-aerosol separation technology ensure the high-precision separation of metal ions, greatly improving the purity of the metal solution. The intelligent adaptive phase change precipitation technology is dynamically adjusted according to the real-time monitored temperature, pH value and metal concentration to ensure that the metal compounds generated in the precipitation process reach a high purity of more than 99.9%. The biocatalytic deposition technology reduces the generated metal compounds to reusable metal materials, further improving the recycling efficiency of resources.

[0096] The present invention adopts a closed-loop intelligent feedback system to monitor and dynamically adjust key parameters such as temperature, pressure and metal concentration in the entire recycling process in real time, maximize the metal recovery rate and resource utilization rate, and ensure harmless treatment of the entire process. This not only effectively solves the problems of low recycling efficiency and serious waste of resources in the prior art, but also greatly reduces the risk of environmental pollution, realizes the efficient recycling of waste lithium-ion battery negative electrode materials, and improves the utilization rate of resources. It has significant advantages such as low energy consumption, high efficiency, strong environmental protection and superior economy. BRIEF DESCRIPTION OF THE DRAWINGS

[0097] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0098] Figure 1 A flowchart of a method for recycling and reusing negative electrode materials of waste lithium-ion power batteries proposed by the present invention;

[0099] Figure 2 It is a schematic diagram of the process of extracting metal ions by the multi-frequency resonance-assisted ion exchange technology in the present invention;

[0100] Figure 3 This is a process flow chart for purifying metal elements using the superconducting magnetic separation technology of the present invention. DETAILED DESCRIPTION

[0101] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, which only illustrate the basic structure of the present invention in a schematic manner, and therefore only show the components related to the present invention.

[0102] refer to Figure 1-3 A method for recycling and reusing the negative electrode material of waste lithium-ion power batteries comprises the following steps:

[0103] S1. Deconstructing waste lithium-ion batteries by selective plasma electrolysis to generate battery negative electrode materials, and separating organic matter and electrolyte in the negative electrode materials to obtain untreated negative electrode powder;

[0104] S2, cooling and crushing the obtained untreated negative electrode powder by supercritical fluid, refining the powder into uniform particles, while retaining the physical structure of the powder to form standardized particles;

[0105] S3. Using multi-frequency resonance-assisted selective ion exchange technology to process standardized particles, extract lithium, nickel, and cobalt metal elements from the particles, remove impurities, and generate a solution containing target metal elements and solid waste residue;

[0106] S4, performing superconducting magnetic separation on the solution containing the target metal element, further purifying the metal element by the magnetic field strength to generate a relatively pure metal solution, and removing the remaining trace impurities;

[0107] S5. Perform nano-aerosol separation on the relatively pure metal solution to further remove fine particle impurities in the solution and generate a metal solution with a purity of more than 99%;

[0108] S6. The high-purity metal solution after aerosol separation is precipitated by intelligent adaptive phase change precipitation technology to generate lithium, nickel, and cobalt metal compound precipitation, so that the metal elements are deposited in a form with a purity of more than 99.9%;

[0109] S7. converting the precipitated metal compound into a recyclable metal material through a biocatalytic deposition technique to form a metal product that can be used in secondary battery manufacturing;

[0110] S8. Use a closed-loop intelligent feedback system to monitor and optimize various parameters of the entire recycling process, use automated adjustment technology to maximize metal recovery rate and resource utilization, and make the entire process harmless.

[0111] In this implementation, S1 specifically includes:

[0112] S11, preliminarily dismantling the negative electrode material of the waste lithium-ion battery to obtain the negative electrode assembly;

[0113] S12, performing low temperature treatment on the negative electrode assembly, controlling the temperature at -20°C to 0°C to prevent damage to the material structure, and performing selective plasma electrolysis;

[0114] S13, plasma electrolysis using a composite electrolyte system, the electrolyte composition includes 0.1M to 1.0M lithium chloride, 0.05M to 0.5M sulfuric acid and 0.01M to 0.1M fluoride;

[0115] S14, controlling the electrolysis conditions, the current density is 0.5A / cm2 to 3A / cm2, the electrolysis time is 10 minutes to 60 minutes, the electrolysis temperature is controlled between 25°C and 45°C, and the pulse current mode is used to optimize the metal separation selectivity;

[0116] S15. During the electrolysis process, lithium cobalt oxide reacts with sulfuric acid, and the target metal elements lithium and cobalt are selectively separated through the reaction, and organic matter and electrolyte are removed;

[0117] S16. After the electrolysis process is completed, the untreated negative electrode powder is filtered out using a solid-liquid separation device, and the retention rate of the metal elements lithium and cobalt in the negative electrode powder is not less than 95%;

[0118] S17, subjecting the obtained negative electrode powder to airflow drying treatment, with the drying temperature controlled at 60° C. to 80° C. to make the particle size of the powder uniform.

[0119] In this implementation, S2 specifically includes:

[0120] S21, preliminarily screening the obtained negative electrode powder to screen out particles with a particle size greater than 50 microns to obtain uniform negative electrode powder;

[0121] S22, placing the screened uniform negative electrode powder in a supercritical fluid cooling and pulverizing device, using supercritical carbon dioxide as a cooling fluid medium;

[0122] S23, during the cooling and pulverizing process, the pressure of the supercritical fluid is controlled between 7.3 MPa and 10 MPa, and the temperature is controlled between 31° C. and 40° C., and the powder particles are refined to a particle size of 10 μm to 50 μm by cooling;

[0123] S24. During the supercritical cooling process, the pulverization effect is optimized by controlling the fluid physical state of the supercritical carbon dioxide:

[0124]

[0125] Where Z is the compression factor, T is the temperature, V m is the actual volume, V c is the critical volume, α is the temperature correction coefficient, T c is the critical temperature;

[0126] S25. By controlling pressure and temperature, the powder particle size is controlled within the target range to obtain standardized particles:

[0127]

[0128] Where d is the powder particle size, P is the pressure of the supercritical fluid, T is the temperature, and k and β are constants related to material properties.

[0129] In this implementation, S3 specifically includes:

[0130] S31, placing the obtained standardized particles in a multi-frequency resonance-assisted ion exchange device to prepare for extraction of lithium, nickel, and cobalt metal ions;

[0131] S32, adding a solution to the ion exchange device, wherein the solution components include 0.5M to 2.0M sulfuric acid and 0.1M to 0.5M lithium chloride, and the solution is used to optimize conductivity and extract lithium ions from the standardized particles;

[0132] S33, controlling the temperature of the solution between 50° C. and 80° C., adjusting the pH value of the solution to 1 to 2, and activating the multi-frequency resonance auxiliary system, controlling the vibration frequency between 10 Hz and 500 Hz, and the vibration amplitude between 0.1 mm and 5 mm, to optimize the metal ion exchange efficiency;

[0133] S34. With the assistance of multi-frequency resonance, the ion exchange reaction begins, and lithium, nickel, and cobalt metal elements are extracted from the standardized particles and enter the solution, while the solid residue is separated from the metal solution;

[0134] S35, calculate the lithium ion extraction rate R by the following formula Li :

[0135]

[0136] Among them, R Li is the extraction rate of lithium ions, is the concentration of lithium ions in the solution, is the initial concentration of lithium ions in the negative electrode material, f is the vibration frequency, A is the vibration amplitude, and α is the correction coefficient;

[0137] S36. After the ion exchange process is completed, use solid-liquid separation equipment to completely separate the lithium, nickel and cobalt metal ions in the solution from the solid residue, so that the purity of the extracted metal solution meets the requirements.

[0138] In this implementation, S4 specifically includes:

[0139] S41, placing a solution containing a target metal element in a superconducting magnetic separation device, and purifying the metal element by controlling the magnetic field strength;

[0140] S42, adjusting the magnetic field strength of the superconducting magnetic separation device to between 0.5 Tesla and 3 Tesla, and preferentially separating the magnetic metal elements through the high magnetic field strength, so that the magnetic metal elements are separated from the solution and enter the purification stage;

[0141] S43. Separate the magnetic metal ions by combining magnetic field strength, separation path, time and movement angle:

[0142]

[0143] Where v is the separation rate of metal ions, q is the charge of metal ions, B is the magnetic field strength, and B r is the reference magnetic field strength, m is the mass of the metal element, θ is the angle between the movement of the metal ions and the magnetic field direction, L is the separation path length, and t is the separation time;

[0144] Combining magnetic field strength and saturation magnetic field characteristics, the separation efficiency of metal ions is optimized:

[0145]

[0146] Where E is the separation efficiency, T is the total operation time, B sat is the saturation magnetic field strength, B r is the reference magnetic field strength, B is the actual magnetic field strength;

[0147] S44. For the weakly magnetic and non-magnetic metal elements in the remaining solution, the magnetic field strength is gradually reduced to 0.5 Tesla to 1 Tesla, and the separation and purification of lithium ions are effectively achieved by adjusting the magnetic field gradient;

[0148] S45. Through multi-level magnetic field control, the relatively pure metal solution is completely separated from the remaining trace impurities, so that the removal of impurities and the purity of the metal solution meet the predetermined requirements;

[0149] S46. Remove impurities and residues from the metal solution through solid-liquid separation equipment, and use the separated metal solution for metal recovery and reuse in the process.

[0150] In this implementation manner, S5 specifically includes:

[0151] S51, placing the obtained relatively pure metal solution in a nano-aerosol separation device, and using nano-aerosol separation technology to further remove fine particle impurities in the solution;

[0152] S52. In the aerosol separation device, the particle size range of the separated particles is controlled between 10 nanometers and 100 nanometers, and the purity of the metal solution is optimized by flow rate and pressure control;

[0153] S53, during the separation process, the removal efficiency of impurity particles E part To quantify:

[0154]

[0155] Among them, E part is the removal efficiency of impurity particles, d crit is the critical particle size for separation, d part is the actual particle size of the impurity particles, P flow is the flow pressure of the aerosol separation equipment, P norm is standard pressure;

[0156] S54. By real-time monitoring of the particle size distribution of the metal solution, separation parameters are adjusted to maintain the stability and uniformity of the solution during the separation process, thereby generating a metal solution with a purity of more than 99%.

[0157] In this implementation manner, S6 specifically includes:

[0158] S61, placing the metal solution with a purity of more than 99% after aerosol separation in an intelligent adaptive phase change precipitation device, and generating lithium, nickel, and cobalt metal compound precipitates by intelligent adaptive phase change precipitation technology;

[0159] S62, intelligent adaptive control monitors the temperature, pH value and metal concentration in the metal solution in real time, dynamically adjusts the precipitation conditions according to the monitoring results, and causes the metal ions to undergo a phase change reaction;

[0160] S63, precipitation rate R of metal compound precip Perform the calculation:

[0161]

[0162] Among them, R precip is the precipitation rate, k is the rate constant, is the concentration of metal ions in the metal solution, T is the temperature, ΔG act is the activation free energy of the phase change reaction, R is the gas constant;

[0163] S64, dynamically adjusting the operating parameters in the precipitation process according to the temperature of 50° C. to 100° C. and the pH value of 1 to 3 fed back by the intelligent adaptive system, so as to promote the precipitation of lithium, nickel and cobalt metal compounds in the form of precipitation;

[0164] S65, monitoring the concentration of the metal solution in the range of 0.1M to 1.0M by the system in real time, and optimizing the precipitation efficiency to generate a metal compound with a purity of more than 99.9%;

[0165] S66. Separate the precipitated metal compounds from the solution using separation equipment to obtain lithium, nickel and cobalt metal compounds.

[0166] In this implementation manner, the S7 specifically includes:

[0167] S71, subjecting the separated lithium, nickel and cobalt metal compounds to biocatalytic deposition, and reducing the metal compounds to reusable metal materials by a specific biocatalyst;

[0168] S72. Use a specific biocatalyst with a concentration of 0.1 mg / L to 10 mg / L to regulate the metal deposition rate R dep :

[0169]

[0170] Among them, R dep is the metal deposition rate, is the concentration of metal ions in the solution, k bio is the activity constant of the biocatalyst, T is the reaction temperature, ΔEbio is the activation energy of the biocatalytic process, R is the gas constant;

[0171] S73. According to the activity and concentration of the catalyst, the deposition time is controlled between 1 hour and 10 hours to achieve stability of the deposition process and optimize the recycling performance of the metal material;

[0172] S74, when the deposition is completed, separating the deposited metal material from the solution by a solid-liquid separation device;

[0173] S75. Post-process the deposited metal material to make it suitable for secondary battery manufacturing and ensure that the mechanical and electrochemical properties of the metal material meet the requirements for reuse.

[0174] In this implementation manner, S8 specifically includes:

[0175] S81. Monitor the temperature, pressure and material separation during the recovery process in real time and adjust the process conditions of metal extraction, separation and precipitation;

[0176] S82, according to temperature feedback, controlling the temperature during the recovery process between 50°C and 100°C, adjusting the operating conditions during the metal extraction and precipitation process, and adjusting the metal recovery rate;

[0177] S83. Through pressure monitoring, dynamically adjust the pressure during the recovery process to optimize the efficiency of metal ion separation and purification:

[0178]

[0179] Among them, P opt is the optimized pressure, P init is the initial pressure, V sys is the system volume, R is the gas constant, T is the system temperature, is the concentration of metal ions after separation, is the initial metal ion concentration;

[0180] S84. Real-time monitoring of material separation, and adjustment of flow and pressure in the process based on feedback of separation efficiency and metal purity:

[0181]

[0182] Among them, F opt is the optimized flow rate, k is the flow constant, is the final metal concentration, T is the temperature, t is the separation time, ΔE is the activation energy of the separation process, and R is the gas constant;

[0183] S85. According to the parameters fed back during the material separation and purification process, adjust the process steps to maximize the metal recovery rate, control energy consumption and resource utilization, and make the entire process harmless.

[0184] Embodiment 1:

[0185] In order to verify the feasibility of the present invention in implementation, the present invention is applied to a waste power battery recycling and processing plant, which processes more than 100 tons of waste lithium-ion power batteries per month. These batteries mainly come from scrapped electric vehicle battery packs and battery cells of energy storage equipment. The negative electrode materials in these waste batteries contain a large amount of valuable metal elements such as lithium, nickel, and cobalt, and have high recycling value. Traditional recycling methods have problems such as high energy consumption, high pollution, and low metal recovery rate. Therefore, a more efficient and environmentally friendly recycling method is needed to solve these problems.

[0186] In this scenario, the method for recycling and reusing negative electrode materials of waste lithium-ion batteries proposed in the present invention greatly improves the recovery rate of metal elements, reduces energy consumption, and reduces the risk of environmental pollution through a series of innovative processes.

[0187] The scrapped lithium-ion power battery was initially disassembled, the negative electrode components in the battery were taken out, and the negative electrode materials were deconstructed by selective plasma electrolysis technology. The temperature was controlled at 30°C, the electrolysis time was set to 40 minutes, and the current density was 2A / cm 2 After electrolysis treatment, the organic matter and the electrolyte are separated to obtain untreated negative electrode powder. Compared with traditional high-temperature heat treatment technology, selective plasma electrolysis reduces energy consumption by about 35% and avoids the harmful gases produced by the combustion of organic matter.

[0188] The negative electrode powder is processed using supercritical fluid cooling and crushing technology. During the crushing process, supercritical carbon dioxide is used as the cooling medium, the pressure is controlled at 9MPa, and the temperature is set to 35°C. The particle size range of the crushed negative electrode powder is 10 microns to 50 microns, and the uniformity of the powder is significantly better than that of traditional mechanical crushing methods. In actual applications, the uniformity of powder particle size is improved by 20%, which provides better conditions for subsequent metal extraction processes.

[0189] In the ion exchange stage, the negative electrode powder is treated by multi-frequency resonance-assisted selective ion exchange technology. During the treatment process, 2M sulfuric acid and 0.3M lithium chloride solution are added. The pH value of the solution is controlled at 1.5 and the temperature is maintained at 60°C. By adjusting the vibration frequency and vibration amplitude, metal elements such as lithium, nickel, and cobalt in the negative electrode material are extracted. In the actual operation of the factory, the metal extraction efficiency is significantly improved. The extraction rate of lithium is 96.5%, the extraction rate of nickel reaches 94%, and the extraction rate of cobalt is 92%. Compared with the traditional chemical leaching process, this result increases the extraction efficiency by about 10%.

[0190] The extracted metal solution is further purified by superconducting magnetic separation technology. The magnetic field strength is controlled at 2.5 Tesla. By precisely adjusting the magnetic field gradient, the magnetic and weakly magnetic metals in the solution are effectively separated. The purity of magnetic metals such as nickel reaches 99.2% after separation, and the purity of weakly magnetic metal lithium reaches 98.8%. Compared with the traditional chemical precipitation method, the magnetic separation process has improved the purification efficiency by 15%. After treatment with nano-aerosol separation technology, fine impurities with particle sizes between 10 nanometers and 100 nanometers in the solution are removed. During the separation process, the flow pressure of the equipment is set to 500Pa, and the stability of the solution is effectively controlled. After this step of treatment, the purity of the final metal solution reaches more than 99.5%, and the metal extraction and separation process achieves high accuracy and efficiency.

[0191] During the precipitation process, the metal solution enters the intelligent adaptive phase change precipitation equipment. The equipment dynamically adjusts the precipitation conditions by real-time monitoring of the temperature and pH value in the solution. Under the action of the monitoring system, the temperature of the precipitation reaction is maintained at 80°C and the pH value is maintained at around 2. After 4 hours of precipitation reaction, lithium, nickel and cobalt metal compounds are generated. The purity of the metal compounds reaches 99.9%, meeting the requirements for high-purity metal recycling. Compared with traditional precipitation methods, the reaction efficiency of the intelligent adaptive phase change precipitation technology is increased by 20%, and human operation errors are reduced by automatically adjusting parameters.

[0192] The metal compounds were reduced using biocatalytic deposition technology. A specific biocatalyst was added to the solution, the concentration was set to 5 mg / L, and the reaction time was 6 hours. After the biocatalytic deposition process, lithium, nickel, and cobalt metal compounds were reduced to reusable metal materials. Compared with traditional chemical deposition methods, biocatalytic deposition not only reduced energy consumption by about 25%, but also significantly improved the purity and recycling performance of the generated metal materials.

[0193] During the entire recycling process, a closed-loop intelligent feedback system is used to monitor and optimize various process parameters in real time. Through the feedback system, the process parameters can be automatically adjusted according to real-time data such as temperature, pressure, and metal concentration to ensure the efficiency and stability of the recycling process. In actual operation, the data of the recycling plant shows that after adopting closed-loop feedback control, the metal recovery rate has increased by about 12%, and the resource utilization rate has reached more than 95%. At the same time, the entire process has achieved harmless treatment.

[0194] Table 1 Data sheet of waste lithium-ion battery recycling process

[0195]

[0196]

[0197] Through the multiple innovative technical steps in the present invention, the recycling efficiency of waste lithium-ion battery negative electrode materials has been significantly improved. The process first uses selective plasma electrolysis technology to perform electrolysis at a relatively low temperature, effectively reducing energy consumption. Compared with traditional high-temperature heat treatment, energy consumption is reduced by 35%. At the same time, the electrolysis time is 40 minutes and the current density is 2A / cm 2 , supercritical fluid cooling pulverization technology plays a key role in the entire recycling process. By refining the negative electrode powder to a uniform particle size of 10-50 microns, the particle size uniformity is improved by 20%, and the multi-frequency resonance-assisted ion exchange technology shows extremely high efficiency in extracting metal elements such as lithium, nickel, and cobalt. By precisely controlling the vibration frequency and amplitude, the extraction rate of lithium reached 96.5%, the extraction rate of nickel reached 94%, and the extraction rate of cobalt reached 92%. In the purification stage of the metal solution, superconducting magnetic separation technology played a vital role. By controlling the magnetic field strength to 2.5 Tesla, the separation of nickel and lithium metals was successfully achieved, with a nickel purity of 99.2% and a lithium purity of 98.8%. This technology improves the accuracy and efficiency of metal purification, and is 15% more efficient than the traditional chemical precipitation method. Subsequently, the nano-aerosol separation technology is used to remove fine impurities with a particle size of 10-100 nanometers, so that the purity of the metal solution reaches more than 99.5%. In the intelligent adaptive phase change precipitation technology, an intelligent feedback control system is used to monitor the temperature and pH value in real time, and the precipitation conditions are automatically adjusted according to the system feedback. After 4 hours of precipitation reaction, the purity of the metal compound reaches 99.9%, and the reaction efficiency is 20% higher than that of the traditional method. The application of biocatalytic deposition technology achieves efficient reduction of metal compounds within 6 hours through 5mg / L biocatalyst, and energy consumption is reduced by 25%. The entire recovery process uses a closed-loop intelligent feedback system to monitor and automatically adjust various process parameters in real time. The system optimizes according to the real-time changes of parameters such as temperature, pressure, and metal concentration, which increases the metal recovery rate by 12% and the resource utilization rate by 95%.

[0198] In summary, the present invention realizes the efficient recovery and reuse of valuable metal elements in the negative electrode materials of waste lithium-ion batteries through a series of innovative technical means, and has high resource utilization, environmental protection and economy.

[0199] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for recycling and reusing the negative electrode material of waste lithium-ion power batteries, characterized in that: The steps include: S1. Deconstructing waste lithium-ion batteries by selective plasma electrolysis to generate battery negative electrode materials, and separating organic matter and electrolyte in the negative electrode materials to obtain untreated negative electrode powder; S2, cooling and crushing the obtained untreated negative electrode powder by supercritical fluid, refining the powder into uniform particles, while retaining the physical structure of the powder to form standardized particles; S3. Using multi-frequency resonance-assisted selective ion exchange technology to process standardized particles, extract lithium, nickel, and cobalt metal elements from the particles, remove impurities, and generate a solution containing target metal elements and solid waste residue; S4, performing superconducting magnetic separation on the solution containing the target metal element, further purifying the metal element by the magnetic field strength to generate a relatively pure metal solution, and removing the remaining trace impurities; S5. Perform nano-aerosol separation on the relatively pure metal solution to further remove fine particle impurities in the solution and generate a metal solution with a purity of more than 99%; S6. The high-purity metal solution after aerosol separation is precipitated by intelligent adaptive phase change precipitation technology to generate lithium, nickel, and cobalt metal compound precipitation, so that the metal elements are deposited in a form with a purity of more than 99.9%; S7. converting the precipitated metal compound into a recyclable metal material through a biocatalytic deposition technique to form a metal product that can be used in secondary battery manufacturing; S8. Use a closed-loop intelligent feedback system to monitor and optimize various parameters of the entire recycling process, use automated adjustment technology to maximize metal recovery rate and resource utilization, and make the entire process harmless.

2. The method for recycling negative electrode materials of waste lithium-ion power batteries according to claim 1, characterized in that: The S1 specifically includes: S11, preliminarily dismantling the negative electrode material of the waste lithium-ion battery to obtain the negative electrode assembly; S12, performing low temperature treatment on the negative electrode assembly, controlling the temperature at -20°C to 0°C to prevent damage to the material structure, and performing selective plasma electrolysis; S13, plasma electrolysis using a composite electrolyte system, the electrolyte composition includes 0.1M to 1.0M lithium chloride, 0.05M to 0.5M sulfuric acid and 0.01M to 0.1M fluoride; S14, controlling the electrolysis conditions, the current density is 0.5A / cm2 to 3A / cm2, the electrolysis time is 10 minutes to 60 minutes, the electrolysis temperature is controlled between 25°C and 45°C, and the pulse current mode is used to optimize the metal separation selectivity; S15. During the electrolysis process, lithium cobalt oxide reacts with sulfuric acid, and the target metal elements lithium and cobalt are selectively separated through the reaction, and organic matter and electrolyte are removed; S16. After the electrolysis process is completed, the untreated negative electrode powder is filtered out using a solid-liquid separation device, and the retention rate of the metal elements lithium and cobalt in the negative electrode powder is not less than 95%; S17, subjecting the obtained negative electrode powder to airflow drying treatment, with the drying temperature controlled at 60° C. to 80° C. to make the particle size of the powder uniform.

3. The method for recycling negative electrode materials of waste lithium-ion power batteries according to claim 1, characterized in that: The S2 specifically includes: S21, preliminarily screening the obtained negative electrode powder to screen out particles with a particle size greater than 50 microns to obtain uniform negative electrode powder; S22, placing the screened uniform negative electrode powder in a supercritical fluid cooling and pulverizing device, using supercritical carbon dioxide as a cooling fluid medium; S23, during the cooling and pulverizing process, the pressure of the supercritical fluid is controlled between 7.3 MPa and 10 MPa, and the temperature is controlled between 31° C. and 40° C., and the powder particles are refined to a particle size of 10 μm to 50 μm by cooling; S24. During the supercritical cooling process, the pulverization effect is optimized by controlling the fluid physical state of the supercritical carbon dioxide: Where Z is the compression factor, T is the temperature, V m is the actual volume, V c is the critical volume, α is the temperature correction coefficient, T c is the critical temperature; S25. By controlling pressure and temperature, the powder particle size is controlled within the target range to obtain standardized particles: Where d is the powder particle size, P is the pressure of the supercritical fluid, T is the temperature, and k and β are constants related to material properties.

4. The method for recycling negative electrode materials of waste lithium-ion power batteries according to claim 1, characterized in that: The S3 specifically includes: S31, placing the obtained standardized particles in a multi-frequency resonance-assisted ion exchange device to prepare for extraction of lithium, nickel, and cobalt metal ions; S32, adding a solution to the ion exchange device, wherein the solution components include 0.5M to 2.0M sulfuric acid and 0.1M to 0.5M lithium chloride, and the solution is used to optimize conductivity and extract lithium ions from the standardized particles; S33, controlling the temperature of the solution between 50° C. and 80° C., adjusting the pH value of the solution to 1 to 2, and activating the multi-frequency resonance auxiliary system, controlling the vibration frequency between 10 Hz and 500 Hz, and the vibration amplitude between 0.1 mm and 5 mm, to optimize the metal ion exchange efficiency; S34. With the assistance of multi-frequency resonance, the ion exchange reaction begins, and lithium, nickel, and cobalt metal elements are extracted from the standardized particles and enter the solution, while the solid residue is separated from the metal solution; S35, calculate the lithium ion extraction rate R by the following formula Li : Among them, R Li is the extraction rate of lithium ions, is the concentration of lithium ions in the solution, is the initial concentration of lithium ions in the negative electrode material, f is the vibration frequency, A is the vibration amplitude, and α is the correction coefficient; S36. After the ion exchange process is completed, use solid-liquid separation equipment to completely separate the lithium, nickel and cobalt metal ions in the solution from the solid residue, so that the purity of the extracted metal solution meets the requirements.

5. The method for recycling negative electrode materials of waste lithium-ion power batteries according to claim 1, characterized in that: The S4 specifically includes: S41, placing a solution containing a target metal element in a superconducting magnetic separation device, and purifying the metal element by controlling the magnetic field strength; S42, adjusting the magnetic field strength of the superconducting magnetic separation device to between 0.5 Tesla and 3 Tesla, and preferentially separating the magnetic metal elements through the high magnetic field strength, so that the magnetic metal elements are separated from the solution and enter the purification stage; S43. Separate the magnetic metal ions by combining magnetic field strength, separation path, time and movement angle: Where v is the separation rate of metal ions, q is the charge of metal ions, B is the magnetic field strength, and B r is the reference magnetic field strength, m is the mass of the metal element, θ is the angle between the movement of the metal ions and the magnetic field direction, L is the separation path length, and t is the separation time; Combining magnetic field strength and saturation magnetic field characteristics, the separation efficiency of metal ions is optimized: Where E is the separation efficiency, T is the total operation time, B sat is the saturation magnetic field strength, B r is the reference magnetic field strength, B is the actual magnetic field strength; S44. For the weakly magnetic and non-magnetic metal elements in the remaining solution, gradually reduce the magnetic field strength to 0.5 Tesla to 1 Tesla, and effectively separate and purify the lithium ions by adjusting the magnetic field gradient; S45. Through multi-level magnetic field control, the relatively pure metal solution is completely separated from the remaining trace impurities, so that the removal of impurities and the purity of the metal solution meet the predetermined requirements; S46. Remove impurities and residues from the metal solution through solid-liquid separation equipment, and use the separated metal solution for metal recovery and reuse in the process.

6. The method for recycling negative electrode materials of waste lithium-ion power batteries according to claim 1, characterized in that: The S5 specifically includes: S51, placing the obtained relatively pure metal solution in a nano-aerosol separation device, and using nano-aerosol separation technology to further remove fine particle impurities in the solution; S52. In the aerosol separation device, the particle size range of the separated particles is controlled between 10 nanometers and 100 nanometers, and the purity of the metal solution is optimized by flow rate and pressure control; S53, during the separation process, the removal efficiency of impurity particles E part To quantify: Among them, E part is the removal efficiency of impurity particles, d crit is the critical particle size for separation, d part is the actual particle size of the impurity particles, P flow is the flow pressure of the aerosol separation equipment, P norm is standard pressure; S54. By real-time monitoring of the particle size distribution of the metal solution, separation parameters are adjusted to maintain the stability and uniformity of the solution during the separation process, thereby generating a metal solution with a purity of more than 99%.

7. The method for recycling and reusing the negative electrode material of waste lithium-ion power batteries according to claim 1, characterized in that: The S6 specifically includes: S61, placing the metal solution with a purity of more than 99% after aerosol separation in an intelligent adaptive phase change precipitation device, and generating lithium, nickel, and cobalt metal compound precipitates by intelligent adaptive phase change precipitation technology; S62, intelligent adaptive control monitors the temperature, pH value and metal concentration in the metal solution in real time, dynamically adjusts the precipitation conditions according to the monitoring results, and causes the metal ions to undergo a phase change reaction; S63, precipitation rate R of metal compound precip Perform the calculation: Among them, R precip is the precipitation rate, k is the rate constant, is the concentration of metal ions in the metal solution, T is the temperature, ΔG act is the activation free energy of the phase change reaction, R is the gas constant; S64, dynamically adjusting the operating parameters in the precipitation process according to the temperature of 50° C. to 100° C. and the pH value of 1 to 3 fed back by the intelligent adaptive system, so as to promote the precipitation of lithium, nickel and cobalt metal compounds in the form of precipitation; S65, monitoring the concentration of the metal solution in the range of 0.1M to 1.0M by the system in real time, and optimizing the precipitation efficiency to generate a metal compound with a purity of more than 99.9%; S66. Separate the precipitated metal compounds from the solution using separation equipment to obtain lithium, nickel and cobalt metal compounds.

8. The method for recycling negative electrode materials of waste lithium-ion power batteries according to claim 1, characterized in that: The S7 specifically includes: S71, subjecting the separated lithium, nickel and cobalt metal compounds to biocatalytic deposition, and reducing the metal compounds to reusable metal materials by a specific biocatalyst; S72. Use a specific biocatalyst with a concentration of 0.1 mg / L to 10 mg / L to regulate the metal deposition rate R dep : Among them, R dep is the metal deposition rate, is the concentration of metal ions in the solution, k bio is the activity constant of the biocatalyst, T is the reaction temperature, ΔE bio is the activation energy of the biocatalytic process, R is the gas constant; S73. According to the activity and concentration of the catalyst, the deposition time is controlled between 1 hour and 10 hours to achieve stability of the deposition process and optimize the recycling performance of the metal material; S74, when the deposition is completed, separating the deposited metal material from the solution by a solid-liquid separation device; S75. Post-process the deposited metal material to make it suitable for secondary battery manufacturing and ensure that the mechanical and electrochemical properties of the metal material meet the requirements for reuse.

9. The method for recycling negative electrode materials of waste lithium-ion power batteries according to claim 1, characterized in that: The S8 specifically includes: S81. Monitor the temperature, pressure and material separation during the recovery process in real time and adjust the process conditions of metal extraction, separation and precipitation; S82, according to temperature feedback, controlling the temperature during the recovery process between 50°C and 100°C, adjusting the operating conditions during the metal extraction and precipitation process, and adjusting the metal recovery rate; S83. Through pressure monitoring, dynamically adjust the pressure during the recovery process to optimize the efficiency of metal ion separation and purification: Among them, P opt is the optimized pressure, P init is the initial pressure, V sys is the system volume, R is the gas constant, T is the system temperature, is the concentration of metal ions after separation, is the initial metal ion concentration; S84. Real-time monitoring of material separation, and adjustment of flow and pressure in the process based on feedback of separation efficiency and metal purity: Among them, F opt is the optimized flow rate, k is the flow constant, is the final metal concentration, T is the temperature, t is the separation time, ΔE is the activation energy of the separation process, and R is the gas constant; S85. According to the parameters fed back during the material separation and purification process, adjust the process steps to maximize the metal recovery rate, control energy consumption and resource utilization, and make the entire process harmless.

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