Recycling method of waste lithium battery negative electrode material binder

Abstract

The invention belongs to the technical field of recycling of waste lithium batteries, and particularly relates to a recycling method of a waste lithium battery negative electrode binder. The method comprises the following steps: treating a negative electrode material containing a negative electrode binder separated by disassembling the waste lithium battery with a solvent, filtering with a filter screen, separating a negative electrode current collector to obtain a mixed solution I containing the negative electrode binder and negative electrode powder, carrying out solid-liquid separation to obtain the negative electrode powder and a mixed solution II containing the negative electrode binder, and distilling to recover the solvent to obtain the negative electrode material containing the negative electrode binder. Adding a precipitation agent I for precipitation, carrying out solid-liquid separation to obtain carboxylated styrene butadiene rubber and a mixed solution IV containing carboxymethyl cellulose, and adding a precipitation agent II for precipitation to obtain carboxymethyl cellulose. The method provided by the invention is high in recovery efficiency, two main components, namely sodium carboxymethyl cellulose and carboxylated styrene-butadiene rubber, in the negative electrode binder are effectively separated, pollutants generated by pyrolysis of the negative electrode binder in a pyrolysis process are avoided, resource waste is reduced, and the method is more environment-friendly.

Description

Technical Field

[0001] The invention belongs to the technical field of recycling waste lithium batteries, and in particular relates to a method for recycling a binder of a negative electrode material of waste lithium batteries. Background Art

[0002] Under the general background of "carbon peak and carbon neutrality", the lithium battery industry has developed rapidly. Lithium-ion power batteries are the core components of new energy, but at the same time, the amount of scrapped lithium batteries is also increasing (patent number: CN 117393749 A). Lithium batteries are usually composed of structures such as positive electrode materials, negative electrode materials, electrolytes and diaphragms (patent CN 117488080 A). Among them, the negative electrode material includes negative electrode graphite powder, negative electrode binder and negative electrode current collector. The properties of the binder are not only conducive to improving the energy density of lithium batteries, but also can significantly reduce the internal resistance of the battery, which plays an important role in improving the performance of lithium batteries (patent number: CN117563557A). The combination of sodium carboxymethyl cellulose, which has a dispersing effect on negative electrode powder graphite and conductive additives, and carboxyl styrene-butadiene rubber, a flexible material with good bonding properties, complement each other when used as a negative electrode binder for lithium batteries. They are indispensable and are the result of long-term practice accumulation in the lithium battery industry.

[0003] However, the presence of negative electrode binder makes it difficult to separate negative electrode powder from negative electrode collector during the recycling process of waste lithium battery negative electrode materials. The stripping of waste lithium ion battery negative electrode powder and negative electrode collector copper foil is the key to achieving efficient recycling of negative electrode materials, which is of great significance and also a very challenging task. If only the conventional friction de-powdering method is adopted, when recycling waste lithium battery negative electrode materials, the copper content in the separated negative electrode powder is seriously exceeded, and further de-coppering by acidic methods is required to achieve effective recycling of negative electrode powder, and wastewater that needs further treatment will still be produced. At present, the main method for stripping waste lithium ion battery negative electrode materials and negative electrode collector copper foil is high temperature calcination method, and the binder remains in the negative electrode powder after high temperature pyrolysis and carbonization (CN109216822A). However, the disadvantage of high temperature calcination method is that toxic gas will be produced during combustion, polluting the environment.

[0004] Therefore, it is necessary to seek a method with simple process and low cost to recover the two main components of negative electrode binder, sodium carboxymethyl cellulose and carboxylated styrene-butadiene rubber, and to effectively separate them. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a method for recycling the binder of the negative electrode material of waste lithium batteries, which has a short process flow, is less time-consuming, and is easy to implement.

[0006] The technical solutions adopted are:

[0007] The steps include:

[0008] (1) disassembling waste lithium batteries in an inert atmosphere to separate negative electrode materials including negative electrode powder, negative electrode current collector and negative electrode binder; wherein the negative electrode binder comprises carboxylated styrene-butadiene rubber and carboxymethyl cellulose;

[0009] (2) adding a solvent to the negative electrode material obtained in step (1), dissolving the negative electrode binder after treatment, so that the negative electrode powder and the negative electrode current collector are effectively separated, filtering through a filter to obtain a mixed solution I containing the negative electrode binder, the negative electrode powder and the solvent; and drying the material on the filter to obtain the negative electrode current collector;

[0010] (3) subjecting the mixed solution I obtained in step (2) to solid-liquid separation to obtain solid material I and mixed solution II, and drying the solid material I to obtain negative electrode powder; wherein the mixed solution II comprises a negative electrode binder and a solvent;

[0011] (4) distilling the mixed solution II obtained in step (3) to recover the solvent, thereby obtaining a mixed solution III, wherein the mixed solution III comprises a negative electrode binder carboxylated styrene-butadiene rubber and sodium carboxymethyl cellulose and a residual solvent;

[0012] (5) adding a precipitating agent I to the mixed solution III obtained in step (4) to precipitate, and then performing solid-liquid separation to obtain a solid substance II and a mixed solution IV, wherein the solid substance II is dried to obtain a carboxylated styrene-butadiene rubber, wherein the mixed solution IV comprises sodium carboxymethyl cellulose, the precipitating agent I, and a residual solvent;

[0013] (6) adding a precipitating agent II to the mixed solution IV obtained in step (5) to precipitate, and then performing solid-liquid separation to obtain a solid substance III and a mixed solution V, wherein the solid substance III is dried to obtain carboxymethyl cellulose, and the mixed solution V comprises the precipitating agent I, the precipitating agent II, and the residual solvent;

[0014] (7) treating the mixed solution V obtained in step (6) to recover the precipitation agent II, the residual solvent and the precipitation agent I.

[0015] Preferably, in the step (2), the solvent is at least one of benzene, toluene, xylene, hexane, cyclohexane, isooctane, ether, ethylene glycol dimethyl ether, petroleum ether, methyl formate, methyl acetate, ethyl formate, ethyl acetate, propyl acetate, ethyl propionate, N-methylpyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, dichloromethane, chloroform, tetrachloromethane, dichloroethane, dichloroethylene, trichloroethylene, tetrachloroethylene, acetonitrile, acetone, tetrahydrofuran, water, methanol, ethanol, propanol, and isopropanol, and the mass ratio of the solvent to the negative electrode material of the waste lithium battery is 2 to 8:1.

[0016] Preferably, in step (2), the treatment refers to at least one of immersion, standing, oscillation, stirring, hydrothermal, solvent thermal, and ultrasound, with a treatment temperature of 10 to 150° C. and a treatment time of 0.1 to 48 h;

[0017] As a further preference, the treatment temperature is 20-50° C. and the treatment time is 0.1-3 h.

[0018] Preferably, in step (2), filtering is performed using a large-pore filter, and the filter screen has a pore size of 4 to 50 meshes.

[0019] Preferably, in step (4), the distillation is one of atmospheric distillation and reduced pressure distillation, the distillation temperature is 30 to 210° C., and the pressure is 0.1 Pa to 100 kPa;

[0020] As a further preference, the temperature is 30 to 90°C.

[0021] Preferably, in the step (5), the precipitating agent I is at least one of sodium fluoride, sodium chloride, sodium bromide, sodium iodide, sodium sulfate, sodium bisulfate, sodium sulfide, sodium hydrosulfide, sodium phosphate, sodium hydrogen phosphate, sodium dihydrogen phosphate, sodium pyrophosphate, sodium nitrate, sodium citrate, sodium carbonate, sodium bicarbonate, ammonium fluoride, ammonium chloride, ammonium bromide, ammonium iodide, ammonium sulfate, ammonium hydrogen sulfate, ammonium sulfide, ammonium hydrosulfide, ammonium phosphate, ammonium hydrogen phosphate, ammonium dihydrogen phosphate, ammonium pyrophosphate, ammonium citrate, ammonium carbonate, ammonium bicarbonate, potassium fluoride, potassium chloride, potassium bromide, potassium iodide, potassium sulfate, potassium hydrogen sulfate, potassium sulfide, potassium hydrosulfide, potassium phosphate, potassium hydrogen phosphate, potassium dihydrogen phosphate, potassium pyrophosphate, potassium nitrate, potassium citrate, potassium carbonate, potassium bicarbonate, magnesium chloride, magnesium bromide, magnesium iodide, magnesium sulfate, magnesium nitrate, and aqueous solutions thereof;

[0022] Wherein, the mass ratio of the precipitation agent I to the mixed solution III is 0.001 to 3:1;

[0023] As a further preference, the mass ratio of the precipitating agent I to the mixed solution III is 0.01 to 0.3:1.

[0024] Preferably, in step (6), the precipitating agent II is at least one of benzoic acid, benzenesulfonic acid, phenol, nitric acid, hydrogen chloride, hydrogen bromide, hydrogen iodide, carbon dioxide, sulfuric acid, sulfurous acid, hydrogen sulfide, formic acid, acetic acid, propionic acid, oxalic acid, citric acid, perchloric acid, permanganic acid, selenic acid, phosphoric acid, sodium dihydrogen phosphate, potassium dihydrogen phosphate, sodium hydrogen sulfate, potassium hydrogen sulfate, and their aqueous solutions.

[0025] Preferably, the mass ratio of the precipitation agent II to the mixed solution IV is 0.00001 to 0.1:1;

[0026] As a further preference, the mass ratio of the precipitation agent II to the mixed solution IV is 0.00001 to 0.01:1.

[0027] Preferably, in step (7), the treatment refers to at least one of distillation, volatilization, evaporation, desalination, crystallization, precipitation, recrystallization, membrane separation, washing, filtration, neutralization, and acidification.

[0028] Preferably, the solid-liquid separation adopts at least one of sedimentation, filtration, membrane filtration, filter pressing, suction filtration, centrifugation, electrophoresis, crystallization and spray drying.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] The method of the present invention is suitable for the effective separation and recovery of sodium carboxymethyl cellulose and carboxyl styrene-butadiene rubber negative electrode binder in negative electrode materials of waste lithium batteries such as waste lithium iron phosphate batteries, waste lithium cobalt oxide batteries, waste lithium manganese oxide batteries, waste nickel cobalt manganese oxide batteries, waste lithium titanate batteries, and waste ternary lithium batteries, and also includes the recovery of negative electrode powder, the recovery of negative electrode current collector copper foil, and the recycling of solvents and precipitation agents.

[0031] The present invention adopts a solvent to dissolve the negative electrode binder, so that the negative electrode material is effectively separated from the negative electrode current collector sheet. Compared with the traditional pyrolysis method, it avoids the generation of pollutants by the pyrolysis of the negative electrode binder during the pyrolysis process, which is more environmentally friendly and safe; and it can maintain the molecular structure of the negative electrode binder, providing a prerequisite for the subsequent recovery of the negative electrode binder.

[0032] Compared with the traditional friction powder removal process, the present invention greatly reduces the negative electrode binder and copper content in the recovered negative electrode powder, and improves the quality and value of the recovered negative electrode powder. The recovered negative electrode powder of the present invention can be used as a negative electrode material for lithium batteries.

[0033] The present invention not only effectively recycles the negative electrode binder in the negative electrode material of waste lithium batteries, but also effectively separates the two main components of sodium carboxymethyl cellulose and carboxy styrene butadiene rubber in the negative electrode binder, thereby improving the basis for the subsequent high-value utilization of sodium carboxymethyl cellulose and carboxy styrene butadiene rubber.

[0034] The carboxymethyl cellulose and carboxylated styrene-butadiene rubber recovered by the present invention can be directly reused as a negative electrode binder for lithium batteries, and can also be used as an anti-re-sedimentation agent and thickener in cosmetics, a sizing agent in the printing and dyeing industry, a paper smoothing agent and sizing agent in the papermaking industry, and the like. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 The invention discloses a flow chart of a method for recycling a binder of a negative electrode material of waste lithium batteries. DETAILED DESCRIPTION

[0036] The accompanying drawings are only for illustrative purposes; in order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0037] Example 1

[0038] like Figure 1 As shown, a method for recycling a binder of a negative electrode material of a waste lithium battery comprises the following steps:

[0039] (1) Dismantling waste lithium iron phosphate square soft-pack batteries in an inert atmosphere to separate negative electrode materials including negative electrode powder, negative electrode current collector, and negative electrode binder carboxylated styrene butadiene rubber and carboxymethyl cellulose;

[0040] (2) adding methanol, acetonitrile and tetrahydrofuran in a ratio of 1:1:1 to the negative electrode material obtained in step (1), with the mass ratio of the solvent to the negative electrode material being 5:1, and subjecting the mixture to ultrasonic treatment for 0.5 h at a temperature of 30° C. to obtain a mixture I, filtering the mixture through a filter screen with a pore size of 20 mesh to obtain a mixed solution I; drying the material on the filter screen to obtain a negative electrode current collector; the mixed solution I comprises a negative electrode binder, a negative electrode powder and a solvent;

[0041] (3) The mixed solution I obtained in step (2) is centrifuged at 10,000 rpm for 15 minutes to obtain a solid I and a mixed solution II; the solid I is dried to obtain a negative electrode powder; the mixed solution II includes a negative electrode binder and a solvent;

[0042] (4) distilling the mixed solution II obtained in step (3) at 0.04 MPa and 30° C. for 1 h, recovering the solvents methanol, acetonitrile and tetrahydrofuran, to obtain a mixed solution III comprising the negative electrode binder carboxylated styrene-butadiene rubber and sodium carboxymethyl cellulose and the residual solvent;

[0043] (5) adding a precipitation agent I (sodium sulfate) to the mixed solution III obtained in step (4), wherein the mass ratio of the precipitation agent I to the mixed solution III is 0.02:1, and after precipitation for 0.5 h, centrifuging at 10000 rpm for 15 min to obtain a solid substance II and a mixed solution IV, wherein the solid substance II is dried at 100° C. for 1 h to obtain a carboxylated styrene-butadiene rubber, and the mixed solution IV comprises sodium carboxymethyl cellulose, the precipitation agent I, and residual solvent;

[0044] (6) Adding precipitation agent II, i.e., 10% sulfuric acid solution, to the mixed solution IV obtained in step (5), the mass ratio of precipitation agent II to mixed solution IV being 10 -5 : 1, after precipitation for 1 hour, centrifuge at 10000 rpm for 15 minutes to obtain solid III and mixed solution V, solid III is dried at 120 ° C for 1 hour to obtain carboxymethyl cellulose, and mixed solution V includes precipitation agent I, precipitation agent II and residual solvent;

[0045] (7) The mixed solution V obtained in step (6) is subjected to reduced pressure distillation at 0.04 MPa and 37° C. for 0.5 h to recover the residual solvent and precipitation agent II (10% sulfuric acid solution), and then filtered to obtain a sulfuric acid solution. The solid is washed, recrystallized, and dried to obtain precipitation agent I, i.e., sodium sulfate.

[0046] Example 2

[0047] A method for recycling a binder for a waste lithium battery negative electrode material, which is different from Example 1 in that:

[0048] The 1:1:1 ratio of methanol, acetonitrile and tetrahydrofuran in step (2) is replaced with 1:1:1 ratio of ethanol, acetonitrile and tetrahydrofuran.

[0049] The remaining parts not mentioned are the same as those in Example 1.

[0050] Example 3

[0051] A method for recycling a binder for a waste lithium battery negative electrode material, which is different from Example 1 in that:

[0052] The 1:1:1 ratio of methanol, acetonitrile and tetrahydrofuran in step (2) is replaced with 1:1:1 ratio of methanol, ethyl acetate and tetrahydrofuran.

[0053] The remaining parts not mentioned are the same as those in Example 1.

[0054] Example 4

[0055] A method for recycling a binder for a waste lithium battery negative electrode material, which is different from Example 1 in that:

[0056] The sodium sulfate in the precipitation agent I in step (5) is replaced by ammonium sulfate, and the mass ratio of the precipitation agent I to the mixed solution III is 0.06:1.

[0057] The remaining parts not mentioned are the same as those in Example 1.

[0058] Example 5

[0059] A method for recycling a binder for a waste lithium battery negative electrode material, which is different from Example 1 in that:

[0060] The 10% sulfuric acid solution of precipitation agent II in step (6) is replaced by 10% sodium bisulfate solution.

[0061] The remaining parts not mentioned are the same as those in Example 1.

[0062] Comparative Example 1

[0063] The traditional pyrolysis process is used to recycle the negative electrode materials of waste lithium batteries. The specific steps are as follows: dismantle the waste lithium batteries to obtain the negative electrode materials of waste lithium batteries; place the above-mentioned negative electrode materials of waste lithium batteries in a nitrogen-protected tubular furnace at 600°C for 3 hours, ball mill for 1.5 hours, and sieve the sieve after grinding. The sieve used for sieving is 120 mesh to obtain the recycled negative electrode powder and the recycled negative electrode current collector.

[0064] Comparative Example 2

[0065] The conventional friction powder removal process is used to recycle the negative electrode material of waste lithium batteries. The difference from Comparative Example 1 is that the operation of calcining at 600° C. for 3 h in a nitrogen-protected tubular furnace is removed.

[0066] Table 1 Comparison of the recovery effect of waste lithium battery negative electrode materials between Examples 1-5 and Comparative Examples 1-2

[0067]

[0068]

[0069] From the comparison of the recovery effects of waste lithium battery negative electrode materials of Examples 1-5 and Comparative Examples 1-2 in Table 1, it can be seen that the method for recovering a binder for waste lithium battery negative electrode materials of the present invention can achieve high-efficiency recovery of negative electrode powder, negative electrode current collector, negative electrode binder carboxyl styrene butadiene rubber and carboxymethyl cellulose, while the negative electrode binder carboxyl styrene butadiene rubber and carboxymethyl cellulose cannot be recovered by the traditional pyrolysis process and the traditional friction de-powdering process; and the content of metallic copper impurities in the negative electrode powder recovered by the present invention is much lower than that of the negative electrode powder recovered by the traditional pyrolysis process (Comparative Example 1) and the traditional friction de-powdering process (Comparative Example 2), thereby improving the quality and value of the recovered negative electrode powder.

[0070] Of course, the above description is not a limitation of the present invention, and the present invention is not limited to the above examples. Changes, modifications, additions or substitutions made by technicians in this technical field within the essential scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. A method for recycling a binder for negative electrode materials of waste lithium batteries, characterized in that: The steps include: (1) disassembling waste lithium batteries in an inert atmosphere to separate negative electrode materials including negative electrode powder, negative electrode current collector and negative electrode binder; wherein the negative electrode binder comprises carboxylated styrene-butadiene rubber and carboxymethyl cellulose; (2) adding a solvent to the negative electrode material obtained in step (1), dissolving the negative electrode binder after treatment, so that the negative electrode powder and the negative electrode current collector are effectively separated, filtering through a filter to obtain a mixed solution I containing the negative electrode binder, the negative electrode powder and the solvent; and drying the material on the filter to obtain the negative electrode current collector; (3) subjecting the mixed solution I obtained in step (2) to solid-liquid separation to obtain solid material I and mixed solution II, and drying the solid material I to obtain negative electrode powder; wherein the mixed solution II comprises a negative electrode binder and a solvent; (4) distilling the mixed solution II obtained in step (3) to recover the solvent to obtain a mixed solution III, wherein the mixed solution III includes carboxylated styrene-butadiene rubber, sodium carboxymethyl cellulose and residual solvent; (5) adding a precipitating agent I to the mixed solution III obtained in step (4) to precipitate, and then performing solid-liquid separation to obtain a solid substance II and a mixed solution IV, wherein the solid substance II is dried to obtain a carboxylated styrene-butadiene rubber, wherein the mixed solution IV comprises sodium carboxymethyl cellulose, the precipitating agent I, and a residual solvent; (6) adding a precipitating agent II to the mixed solution IV obtained in step (5) to precipitate, and then performing solid-liquid separation to obtain a solid substance III and a mixed solution V, wherein the solid substance III is dried to obtain carboxymethyl cellulose, and the mixed solution V comprises the precipitating agent I, the precipitating agent II, and the residual solvent; (7) treating the mixed solution V obtained in step (6) to recover the precipitation agent II, the residual solvent and the precipitation agent I.

2. The method for recycling a binder for negative electrode materials of waste lithium batteries according to claim 1, characterized in that: In the step (2), the solvent is at least one of benzene, toluene, xylene, hexane, cyclohexane, isooctane, ether, ethylene glycol dimethyl ether, petroleum ether, methyl formate, methyl acetate, ethyl formate, ethyl acetate, propyl acetate, ethyl propionate, N-methylpyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, dichloromethane, chloroform, tetrachloromethane, dichloroethane, dichloroethylene, trichloroethylene, tetrachloroethylene, acetonitrile, acetone, tetrahydrofuran, water, methanol, ethanol, propanol, and isopropanol, and the mass ratio of the solvent to the negative electrode material of the waste lithium battery is 2 to 8:

1.

3. The method for recycling a binder for negative electrode materials of waste lithium batteries according to claim 1, characterized in that: In the step (2), the treatment refers to at least one of immersion, standing, oscillation, stirring, hydrothermal, solvent thermal, and ultrasound, the treatment temperature is 20 to 50° C., and the treatment time is 0.1 to 3 hours.

4. The method for recycling a binder for negative electrode materials of waste lithium batteries according to claim 1, characterized in that: In the step (2), the pore size of the filter screen is 4 to 50 meshes.

5. The method for recycling a binder for negative electrode materials of waste lithium batteries according to claim 1, characterized in that: In the step (4), the distillation is one of atmospheric distillation and reduced pressure distillation, the temperature is 30 to 90° C., and the pressure is 0.1 Pa to 100 kPa.

6. The method for recycling a binder for negative electrode materials of waste lithium batteries according to claim 1, characterized in that: In the step (5), the precipitation agent I is at least one of sodium fluoride, sodium chloride, sodium bromide, sodium iodide, sodium sulfate, sodium bisulfate, sodium sulfide, sodium hydrosulfide, sodium phosphate, sodium hydrogen phosphate, sodium dihydrogen phosphate, sodium pyrophosphate, sodium nitrate, sodium citrate, sodium carbonate, sodium bicarbonate, ammonium fluoride, ammonium chloride, ammonium bromide, ammonium iodide, ammonium sulfate, ammonium hydrogen sulfate, ammonium sulfide, ammonium hydrosulfide, ammonium phosphate, ammonium hydrogen phosphate, ammonium dihydrogen phosphate, ammonium pyrophosphate, ammonium citrate, ammonium carbonate, ammonium bicarbonate, potassium fluoride, potassium chloride, potassium bromide, potassium iodide, potassium sulfate, potassium hydrogen sulfate, potassium sulfide, potassium hydrosulfide, potassium phosphate, potassium hydrogen phosphate, potassium dihydrogen phosphate, potassium pyrophosphate, potassium nitrate, potassium citrate, potassium carbonate, potassium bicarbonate, magnesium chloride, magnesium bromide, magnesium iodide, magnesium sulfate, magnesium nitrate, and aqueous solutions thereof, and the mass ratio of the precipitation agent I to the mixed solution III is 0.01 to 0.3:

1.

7. The method for recycling a binder for negative electrode materials of waste lithium batteries according to claim 1, characterized in that: In the step (6), the precipitating agent II is at least one of benzoic acid, benzenesulfonic acid, phenol, nitric acid, hydrogen chloride, hydrogen bromide, hydrogen iodide, carbon dioxide, sulfuric acid, sulfurous acid, hydrogen sulfide, formic acid, acetic acid, propionic acid, oxalic acid, citric acid, perchloric acid, permanganic acid, selenic acid, phosphoric acid, sodium dihydrogen phosphate, potassium dihydrogen phosphate, sodium hydrogen sulfate, potassium hydrogen sulfate, and their aqueous solutions.

8. The method for recycling a binder for negative electrode materials of waste lithium batteries according to claim 7, characterized in that: The mass ratio of the precipitating agent II to the mixed liquid IV is 0.00001-0.01:

1.

9. The method for recycling a binder for negative electrode materials of waste lithium batteries according to claim 1, characterized in that: In the step (7), the treatment refers to at least one of distillation, volatilization, evaporation, desalination, crystallization, precipitation, recrystallization, membrane separation, washing, filtration, neutralization, and acidification.

10. The method for recycling a binder for negative electrode materials of waste lithium batteries according to claim 1, characterized in that: The solid-liquid separation adopts at least one of sedimentation, filtration, membrane filtration, filter pressing, suction filtration, centrifugation, electrophoresis, crystallization and spray drying.

Images