Recovery method of battery cathode material

Abstract

The present invention provides a method for recycling a battery cathode material, comprising the following steps: subjecting the battery cathode material to pretreatment to obtain a cathode powder and a rough current collector; mixing the rough current collector with water for reaction, followed by filtration, to obtain a first filter residue and a first filtrate; mixing and washing the first filter residue with water and starch, and performing solid-liquid separation to obtain a refined current collector and starch water; mixing the starch water with the cathode powder and sodium sulfate for roasting, adding water for mixing and filtering after roasting, to obtain a second filter residue and a second filtrate; performing carbonization treatment on the second filtrate and the first filtrate to obtain a carbonate precipitate of a first metal material. This method realizes the preferential extraction of the first metal material through the first-stage recycling, and re-extracts the remaining first metal material by the roasting reduction method during the second-stage recycling. The method for recycling the cathode material in the second stage can improve the total recovery rate of the metal material.

Description

Technical Field

[0001] The present invention relates to the technical field of waste battery recycling, and particularly to a method for recycling battery cathode materials. Background Art

[0002] With the development of the new energy industry, the production and sales volume of lithium-ion batteries have increased exponentially. According to the service life of power batteries of 5 - 8 years, power batteries are about to usher in a large-scale retirement wave, so battery recycling is becoming a hot topic in the industry. Battery recycling mainly includes aspects such as material repair, cascade utilization, pretreatment, and resource recycling. In terms of resource recycling, with the skyrocketing price of lithium salts, lithium recycling has gradually become a key research direction for battery resource recycling.

[0003] Currently, there are mainly the following two resource recycling processes for the cathode sheet: First, wet lithium extraction after crushing and separation: The cathode sheet is crushed and screened to obtain cathode powder and coarse aluminum material, and then the cathode powder is processed through wet processes such as leaching and extraction to achieve the resource recycling of metals such as nickel, cobalt, manganese, and lithium. Processes such as pickling and salt washing are used to leach the metals such as nickel, cobalt, manganese, and lithium doped or wrapped in the coarse aluminum material, and the leaching residue is high-purity aluminum slag. Since the cathode sheet is composed of cathode powder and aluminum current collector bonded by a binder, the above process will cause the cathode powder to contain a large amount of organic matter, reducing the recovery rate of metals such as nickel, cobalt, manganese, and lithium; moreover, this process will leach impurities such as aluminum in the coarse aluminum material, resulting in impure leached metals such as nickel, cobalt, manganese, and lithium, and there will also be some residues of metals such as nickel, cobalt, manganese, and lithium in the leaching residue, which will directly increase the complexity of the subsequent process and affect the metal recovery rate. Second, wet lithium extraction after crushing, separation, and roasting: The used lithium battery is disassembled to obtain the cathode sheet, the cathode sheet is crushed, screened, and roasted, and then wet lithium extraction is carried out on the roasted material. This process will cause some of the cathode sheets after crushing and screening to be unroasted, and the metals such as nickel, cobalt, manganese, and lithium in them are not recovered, resulting in a reduction in the metal recovery rate. Summary of the Invention

[0004] In view of at least some of the problems such as incomplete metal recovery and low metal recovery rate in the traditional battery cathode material recycling process, the present invention provides a method for recycling battery cathode materials.

[0005] According to one aspect of the present invention, there is provided a method for recycling battery cathode materials, including the following steps:

[0006] The battery cathode material is pretreated to obtain cathode powder and coarse current collector material;

[0007] The coarse current collector material is mixed and reacted with water, and then filtered to obtain a first filter residue and a first filtrate;

[0008] The first filter residue is mixed and washed with water and starch, and solid-liquid separation is carried out to obtain a refined current collector material and starch water;

[0009] Mix the starch water, the positive electrode powder, and a sulfate for roasting. After roasting, add water, mix, and filter to obtain a second filter residue and a second filtrate.

[0010] Perform carbonization treatment on the second filtrate and the first filtrate to obtain a carbonate precipitate of the first metal material.

[0011] In the above technical solution of the present invention, first mix the rough current collector material with water for reaction and filter to obtain a first filter residue and a first filtrate, which can cause part of the first metal material to enter the first filtrate with the liquid phase, realizing the separation and recovery of part of the first metal material from the rough current collector material. At this time, part of the first metal material still remains in the first filter residue; then use starch and water to mix and wash the first filter residue, and perform solid-liquid separation to obtain a refined current collector material and starch water, so that the current collector material and the positive electrode active material are basically completely separated. The obtained refined current collector material is a high-purity current collector material. At this time, the recovery of the current collector material is completed, and other positive electrode active materials enter the starch water; then mix the starch water, the positive electrode powder, and a sulfate for roasting. After roasting, add water, mix, and filter to obtain a second filter residue and a second filtrate, so that the first metal material in the starch water and the positive electrode powder enters the second filtrate; finally, extract the first metal material in the first filtrate and the second filtrate, and the recovery of the first metal material is completed. In this way, first perform the first-stage recovery on the rough current collector material to obtain the first filtrate, and then perform the second-stage recovery on the rough current collector material to obtain the second filtrate, which can improve the total recovery rate of the first metal material, and can also realize the synchronous recovery of the current collector material, improving the resource recovery effect of the battery positive electrode material.

[0012] In a further preferred embodiment, after obtaining the first filter residue and the first filtrate, the method specifically includes the following steps:

[0013] Screen the first filter residue to obtain a residue material and a powder material.

[0014] Mix and wash the residue material with water and starch, and perform solid-liquid separation to obtain a refined current collector material and starch water.

[0015] Mix the starch water, the powder material, the positive electrode powder, and a sulfate for roasting. After roasting, add water, mix, and filter to obtain a second filter residue and a second filtrate.

[0016] Perform carbonization treatment on the second filtrate and the first filtrate to obtain a carbonate precipitate of the first metal material.

[0017] In this solution, the first filter residue is first screened to obtain a slag material and a powder material, so that part of the positive electrode active material coated or mixed in the first filter residue enters the powder material, and the current collector material enters the slag material. In this way, the separation of the positive electrode active material and the current collector material is further achieved, which is conducive to the purification and recovery of the positive electrode active material and the current collector material respectively, thereby improving the recovery rate of the battery positive electrode material.

[0018] In a further preferred embodiment, the pretreatment specifically comprises the following steps: subjecting the battery positive electrode material to multi-stage crushing and screening, and collecting the fine material after each stage of crushing and screening to obtain the positive electrode powder, and collecting the coarse material after the last stage of crushing and screening to obtain the current collector coarse material;

[0019] Preferably, the particle size of the current collector coarse material does not exceed 3 mm, and the particle size of the positive electrode powder is less than 200 mesh;

[0020] Preferably, the particle size of the current collector coarse material does not exceed 0.85 mm, and the particle size of the positive electrode powder is less than 300 mesh;

[0021] Preferably, the current collector content in the positive electrode powder is less than 2%.

[0022] Since there is a binder between the current collector and the positive electrode powder, simple mechanical crushing cannot completely destroy the structure of the binder, resulting in a large amount of positive electrode powder remaining on the current collector coarse material. In addition, the current collector generally has good ductility and is easily kneaded into an irregular shape during the crushing process, which will also contain mixed positive electrode powder, making it difficult to separate the current collector from the positive electrode powder. In this scheme, after the battery positive electrode material is subjected to multi-stage crushing and screening, the current collector coarse material is located on the sieve due to large particles and insufficient crushing, while the positive electrode powder is located under the sieve due to its small particle size. By combining the difference in particle size with multi-stage crushing and screening, the positive electrode powder is gradually separated from the current collector coarse material, thereby improving the separation effect of the current collector coarse material and the positive electrode powder.

[0023] In a further preferred embodiment, before obtaining the first filter residue and the first filtrate, the coarse current collector material is mixed with water and sodium sulfate and ball-milled;

[0024] Preferably, the ball milling specifically comprises the following steps: mixing the coarse current collector material with sodium sulfate at a mass ratio of 1:3 to 1:8, then mixing and ball milling with water at a solid-liquid mass ratio of 1:5 to 1:15, and filtering to obtain a first filter residue and a first filtrate.

[0025] In this solution, the rough current collector material is fully mixed and contacted with water and sodium sulfate by ball milling, which is beneficial to promote the leaching of the first metal material from the rough current collector material, and can enhance the preferential lithium extraction effect of the rough current collector material, thereby improving the recovery rate of the first metal material.

[0026] In a further preferred embodiment, the first filter residue is wet-screened to obtain a slag material and a powder material;

[0027] Preferably, the wet screening specifically includes the following steps: mixing the first filter residue with water at a mass ratio of 1:10 to 1:20, screening with 200 to 300 mesh, the oversize material is the slag material, and the undersize material is the powder material.

[0028] In this solution, the wet screening method is adopted, so that the separation cost of the positive electrode active material and the current collector material is low, and the separation process is fast and convenient, and the fine powder material in the current collector material can be effectively separated.

[0029] In a further preferred embodiment, the mixing and washing method of the slag material with water and starch specifically includes: making a slurry by mixing the slag material with water at a mass ratio of 1:5 to 1:15, and then adding starch at a mass ratio of starch to the slag material of 1:3 to 1:8 for washing, and performing solid-liquid separation to obtain a refined current collector material and starch water.

[0030] In this solution, the positive electrode active material in the slag material is washed out by using the adsorbability of starch, which will not damage the current collector material in the slag material, ensures the chemical properties of the slag material, and reduces its impurity content. At the same time, by extracting the positive electrode active material in the slag material, the total recovery rate of the positive electrode active material can be improved.

[0031] In a further preferred embodiment, before obtaining the second filter residue and the second filtrate, the following treatment steps are included:

[0032] Mix the starch water with the powder material, the positive electrode powder, and sulfate, and then perform roasting to obtain a roasted material, and then add water to the roasted material for mixing and ball milling to obtain a ball-milled mixture;

[0033] Adjust the pH of the ball-milled mixture to a first pH value, and then filter to obtain a second filter residue and a second filtrate.

[0034] In this solution, the starch water is mixed with the powder material, the positive electrode powder, and sulfate for roasting. After roasting, the starch has good carbon reducing properties, which is beneficial to the subsequent leaching of the first metal material; and after adding water to the roasted material for mixing, by adjusting the pH, the first metal material is dissolved into the second filtrate, so as to further extract the first metal material contained in the starch water and the powder material, and at the same time extract the first metal material contained in the positive electrode powder, thereby improving the recovery rate of the battery positive electrode material.

[0035] In a further preferred embodiment, after mixing the starch water with the powder material, the positive electrode powder, and sulfate, the method further includes:

[0036] Pelletize the mixture to obtain a positive electrode pellet, and roast the positive electrode pellet.

[0037] In this solution, the mixture of starch water, powder material, positive electrode powder, and sulfate is pelletized and then calcined, which can improve the calcination effect. Moreover, the starch water generated after starch washing can be used as an additive for pelletizing and granulating the powder material, which is beneficial to forming positive electrode pellets by granulation and can also reduce costs. After pelletization and calcination, starch has good carbon reduction ability, providing a reducing agent for subsequent steps and further reducing costs.

[0038] In a further preferred solution, the pelletization specifically includes the following steps: mixing the positive electrode powder and the powder material at a mass ratio of 3:1 to 5:1 to obtain a first mixture, adding sulfate at a mass ratio of the first mixture to sulfate of 1:3 to 1:7 to obtain a second mixture, and then adding the starch water at a mass ratio of the second mixture to the starch water of 2:1 to 8:1 for mixing and slurry adjustment, and then pelletizing the material to obtain positive electrode pellets.

[0039] Preferably, the calcination temperature is 400 - 500 °C, the calcination time is 4 - 6 hours, and the mass ratio of the calcined material to water is 1:5 to 1:15.

[0040] Preferably, the first pH value is 6.5 - 7.5.

[0041] Under the pelletization and calcination conditions selected in this solution, it is beneficial to further improve the recovery rate of the battery positive electrode material.

[0042] In a further preferred solution, the specific steps of the carbonization treatment include: introducing a reducing gas into the first filtrate and the second filtrate to obtain a carbonate precipitate of the first metal material. Through the above method, the first metal material in the first filtrate and the second filtrate can be precipitated to facilitate its recycling.

[0043] In a further preferred solution, the method further includes the following step: performing wet impurity removal on the second filter residue to obtain a second metal material.

[0044] Since the positive electrode active material generally includes multiple metal materials, during the treatment of starch water and positive electrode powder, part of the positive electrode active material will enter the second filter residue. Thus, by reprocessing the second filter residue, the second metal material contained therein can be extracted, thereby fully recovering the metal materials in the battery positive electrode material.

[0045] In a further preferred solution, the battery is a lithium-ion battery, the first metal material is a lithium material, and the second metal material is other metal materials in the battery positive electrode material except lithium; preferably, the second metal material is at least one of nickel, cobalt, and manganese.

[0046] In this solution, lithium in the lithium-ion battery can be preferentially extracted and recycled. The total recovery rate of lithium can be increased through a two-stage recycling method. Moreover, metal materials such as aluminum current collectors, nickel, cobalt, and manganese in the lithium-ion battery can be recycled, achieving the purpose of fully recycling the cathode material of the lithium battery.

[0047] In summary, the recycling method of the battery cathode material provided by the present invention has at least the following beneficial effects:

[0048] 1. In the present invention, part of the first metal material in the current collector rough material is extracted through the first-stage recycling, realizing the preferential extraction of the first metal material such as lithium. During the second-stage recycling, the remaining first metal material in the current collector rough material is extracted again by the roasting reduction method. The method of multi-stage and step-by-step recycling of the first metal material can effectively avoid the problem of metal material loss caused by impurity carrying, reduce the impurity content. Moreover, during the second-stage recycling, the first metal material in the cathode powder is extracted, improving the recovery rate of the metal material in the cathode powder. By separately recycling the cathode materials in the current collector rough material and the cathode powder, the total recovery rate of the metal material is increased.

[0049] 2. Adding water and sodium sulfate to the current collector rough material can effectively extract the first metal material, and the auxiliary materials of this method have little influence on the product quality, which is beneficial to the effective recycling of all components of the metal material in the cathode powder in the subsequent steps.

[0050] 3. Using the adsorption property of starch to recycle the powder materials, the granulation property makes the powder materials form into balls. The pelletization can effectively improve the extraction effect of the first metal material, ensuring that the added reagents are in full contact with the pelletized materials. At the same time, the skeleton carbon structure of the starch itself after calcination has good carbon reducibility, providing a reducing agent for the subsequent steps and further reducing the cost.

[0051] 4. Mixing and calcining part of the metal materials in the cathode powder and the starch water through the lithium extraction process combining sulfate and organic carbon original starch roasting, its structure changes and is transformed into easily leachable metal materials, thereby increasing the recovery rate of the first metal material.

[0052] 5. The second filter residue is treated by a wet method, and the second metal material therein can be recycled, realizing the full-component recycling of the battery cathode material. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0054] Figure 1 It is a flowchart of the method for recycling the cathode material of the battery provided by the embodiment of the present invention. Detailed implementation manners

[0055] It should be understood that the specific embodiments given herein are for the purpose of explaining to those skilled in the art, and are merely exemplary rather than restrictive.

[0056] In the following description, many specific details are set forth to provide a thorough understanding of the present invention. However, it is obvious to those of ordinary skill in the art that the present invention does not need to adopt specific details to be practiced. In other cases, well-known steps or operations are not described in detail to avoid obscuring the present invention.

[0057] Referring to Figure 1 As shown, the method for recycling the cathode material of the battery provided by the embodiment of the present invention includes the following steps: subjecting the cathode material of the battery to pretreatment to obtain cathode powder and rough current collector material; mixing the rough current collector material with water for reaction, and then filtering to obtain a first filter residue and a first filtrate; mixing and stirring the first filter residue with water and starch, and performing solid-liquid separation to obtain a refined current collector material and starch water; roasting the starch water, cathode powder, and sulfate, adding water for mixing and filtering after roasting to obtain a second filter residue and a second filtrate; performing carbonization treatment on the second filtrate and the first filtrate to obtain a carbonate precipitate of the first metal material.

[0058] Among them, the battery has a lithium-containing cathode material in the positive electrode part and a graphite-containing component in the negative electrode part. For example, the battery can be a ternary lithium battery, a lithium cobalt oxide battery, a lithium manganese oxide battery, etc. The cathode material of the battery is a cathode sheet, the current collector is an aluminum material, the first metal material is a lithium material, and the second metal material is other metal materials except lithium in the cathode material of the battery, such as nickel, cobalt, manganese, etc. In the embodiment of the present invention, two-stage lithium extraction is performed on the cathode sheet. Sodium sulfate can be added during the first-stage lithium extraction. The heat released by the reaction of aluminum in the rough aluminum material with water is used to improve the lithium extraction rate. Moreover, Al has reducibility, and under the action of the additive sodium sulfate, a part of the lithium with stronger activity can be separated and extracted first. The lithium recovery rate in this stage is above 50%; during the second-stage lithium extraction, the pellet material is controlled to be reduced and roasted with sulfate and organic carbon for lithium extraction. The total lithium recovery rate of the two stages can reach more than 98%. Through the above-mentioned segmented lithium extraction method, the separation and extraction of aluminum and other metal materials such as nickel, cobalt, and manganese are synchronously realized, which can reduce energy consumption.

[0059] In some alternative embodiments, the method for recycling the cathode material of the battery includes the following steps:

[0060] S1. Disassemble the waste lithium-ion battery to obtain a cathode sheet.

[0061] S2. Subject the cathode material of the battery, that is, the cathode sheet, to pretreatment to obtain cathode powder and rough current collector material, that is, rough aluminum material.

[0062] Optionally, step S2 specifically includes the following steps: The positive electrode sheet is crushed once, and the particle size of the crushed material is kept within 3 mm, and then screened with a 200-mesh sieve. The material passing through the sieve is the first-stage positive electrode powder, and the material remaining on the sieve is the raw material for secondary crushing; the material remaining on the sieve after the first sorting is crushed twice, and the particle size of the crushed material is kept within 2 mm, and then screened with a 200-mesh sieve. The material passing through the sieve is the second-stage positive electrode powder, and the material remaining on the sieve is the raw material for tertiary crushing; the material remaining on the sieve after the second sorting is crushed three times, and the crushed material is kept within 1 mm, and then screened with a 300-mesh sieve. The material passing through the sieve is the third-stage positive electrode powder, and the material remaining on the sieve is the raw material for quaternary crushing; the material remaining on the sieve after the third sorting is crushed, and the crushed material is kept within 0.85 mm, and then screened with a 300-mesh sieve. The material passing through the sieve is the fourth-stage positive electrode powder, and the material remaining on the sieve is the coarse aluminum material; the first-stage positive electrode powder, the second-stage positive electrode powder, the third-stage positive electrode powder, and the fourth-stage positive electrode powder are mixed to obtain the final positive electrode powder, and the aluminum content in the positive electrode powder is controlled below 2%.

[0063] It can be understood that in other alternative embodiments, the number of crushing and sorting times of the positive electrode sheet may not be limited to four times. For example, it can also be crushed five times, six times, seven times, etc.

[0064] S3. After mixing and reacting the collector coarse material, i.e., the coarse aluminum material, with water and sodium sulfate, filter to obtain the first filter residue and the first filtrate.

[0065] Optionally, step S3 specifically includes the following steps: The coarse aluminum material and sodium sulfate are mixed in a mass ratio of 1:3 to 1:8, and the mixture is mixed and ball-milled with water in a solid-liquid mass ratio of 1:5 to 1:15, and then filtered and separated to obtain the first filter residue, i.e., the ball-milled residue, and the first filtrate, i.e., the first-stage lithium extraction solution.

[0066] Optionally, an auxiliary medium is added during the ball-milling process. Among them, the auxiliary medium can be zirconia beads, steel beads, etc. For example, zirconia beads with three different diameters of 5 mm, 10 mm, and 15 mm can be added during the ball-milling process, which is beneficial to improving the lithium extraction effect by ball-milling. It can be understood that in other alternative embodiments, the size of the zirconia beads is not limited to the above examples. For example, the diameter of the zirconia beads can also be 20 mm, 25 mm, 30 mm, etc.

[0067] S4. After screening the first filter residue, i.e., the ball-milled residue, obtain the slag material and the powder material.

[0068] Optionally, step S4 specifically includes the following steps: Mix the first filter residue with water in a mass ratio of 1:10 to 1:20, and perform wet screening with 200 to 300 meshes. The material remaining on the sieve is the slag material, i.e., the aluminum slag, and the material passing through the sieve is the powder material, i.e., the nickel-cobalt-manganese powder.

[0069] S5. Mix and wash the slag material, i.e., aluminum slag, with water and starch, and perform solid-liquid separation to obtain the current collector concentrate, i.e., high-purity aluminum slag and starch water.

[0070] Optionally, step S5 specifically includes the following steps: Prepare a slurry by mixing the slag material and water at a mass ratio of 1:5 to 1:15, then add starch at a mass ratio of starch to slag material of 1:3 to 1:8 for washing, and perform solid-liquid separation to obtain the current collector concentrate, i.e., high-purity aluminum slag and starch water. Among them, by washing the aluminum slag with starch, the total content of nickel, cobalt, manganese, and lithium in the aluminum slag can be controlled within 1-2%, greatly improving the purity of the recycled aluminum. Moreover, acid is not used in the process of recycling aluminum, which can avoid reducing the recycling value of aluminum by acid washing and causing pollution.

[0071] S6. After mixing the starch water with the powder materials, i.e., nickel-cobalt-manganese powder, cathode powder, and sulfate, pelletize the mixture to obtain cathode pellets.

[0072] Optionally, step S6 specifically includes the following steps: Mix the cathode powder and the powder materials at a mass ratio of 3:1 to 5:1 to obtain a first mixture, add sulfate at a mass ratio of the first mixture to sulfate of 1:3 to 1:7 to obtain a second mixture, then add starch water at a mass ratio of the second mixture to starch water of 2:1 to 8:1 for mixing and slurry adjustment. Use a pelletizer with an inclination angle of 15° to 45° and control the rotation speed at 300-500 r / min to pelletize the material, and control the pelletizing particle size to be within 6 mm to obtain cathode pellets.

[0073] Optionally, the sulfate is at least one of sodium sulfate, ammonium sulfate, potassium sulfate, and calcium sulfate.

[0074] S7. Roast the cathode pellets to obtain a roasted material, and then add water to the roasted material for mixing and ball milling to obtain a ball-milled mixture.

[0075] Optionally, the roasting temperature is 400-500 °C, the roasting time is 4-6 hours, and the mass ratio of the roasted material to water is 1:5 to 1:15; for example, the roasting temperature can be 400 °C, 410 °C, 420 °C, 430 °C, 440 °C, 450 °C, 460 °C, 470 °C, 480 °C, 490 °C, 500 °C or any value between 400-500 °C; the roasting time can be 4 h, 4.2 h, 4.4 h, 4.6 h, 4.8 h, 5 h, 5.2 h, 5.4 h, 5.6 h, 5.8 h, 6 h or any value between 4-6 h; the mass ratio of the roasted material to water can be 1:5, 1:6, 1:7, 1:8, 1:9, 1:10, 1:11, 1:12, 1:13, 1:14, 1:15 or any value between 1:5 to 1:15.

[0076] Optionally, an auxiliary medium is added during the ball milling process, where the auxiliary medium can be zirconia beads, steel balls, etc. For example, zirconia beads with three different diameters of 5 mm, 10 mm, and 15 mm can be added during the ball milling process, which is beneficial to improving the lithium extraction effect of ball milling. It can be understood that in other alternative embodiments, the size of the zirconia beads is not limited to the above examples. For example, the diameter of the zirconia beads can also be 20 mm, 25 mm, 30 mm, etc.

[0077] S8. After adjusting the pH of the ball milling mixture to the first pH value, filter to obtain a second filter residue and a second filtrate.

[0078] Optionally, the first pH value is 6.5 - 7.5. For example, the first pH value can be 6.5, 6.6, 6.7, 6.8, 6.9, 7.0, 7.1, 7.2, 7.3, 7.4, 7.5 or any value between 6.5 - 7.5.

[0079] Optionally, step S8 specifically includes the following steps: Add sulfuric acid to the ball milling mixture to adjust the pH to 6.5 - 7.5, then filter and separate to obtain a second filter residue, i.e., the ball milling residue, and a second filtrate, i.e., the lithium-rich solution.

[0080] S9. Carbonize the second filtrate, i.e., the lithium-rich solution, and the first filtrate, i.e., the lithium extraction solution, to obtain a carbonate precipitate of the first metal material.

[0081] Optionally, the second filtrate and the first filtrate can be carbonized separately to obtain the first metal material, or the second filtrate and the first filtrate can be mixed and carbonized together to obtain the first metal material.

[0082] Optionally, step S9 specifically includes the following steps: Pass a reducing gas, such as carbon dioxide, into the mixed solution of the first filtrate and the second filtrate to obtain a carbonate precipitate of the first metal material, such as a lithium carbonate precipitate. Wash, dehydrate, remove impurities, separate, and dry the lithium carbonate precipitate to obtain lithium carbonate, and the lithium recovery rate in the whole process reaches more than 98%.

[0083] S10. Perform wet impurity removal on the second filter residue, i.e., the ball milling residue, to obtain a second metal material.

[0084] Optionally, the second metal material is at least one of nickel, cobalt, and manganese. For example, the second metal material can be a nickel material, a cobalt material, a manganese material, a mixture of nickel and cobalt, a mixture of nickel and manganese, a mixture of cobalt and manganese, or a mixture of nickel, cobalt, and manganese.

[0085] Optionally, step S10 specifically includes the following steps: Perform wet impurity removal and purification on the second filter residue to obtain nickel cobalt manganese salts.

[0086] In order to make the objectives, technical solutions and beneficial effects of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to specific embodiments. However, the specific embodiments described are only used to explain the present invention and are not used to limit the present invention.

[0087] Embodiment 1

[0088] The method for recycling the cathode material of the battery in this embodiment includes the following steps:

[0089] Disassemble the waste ternary lithium-ion battery to obtain the cathode sheet and anode sheet inside the battery;

[0090] After subjecting the cathode sheet to multi-stage crushing and sorting, obtain cathode powder and coarse aluminum material, control the particle size of the coarse aluminum material to be above 300 mesh, and control the aluminum content in the cathode powder to be below 2%;

[0091] Mix the coarse aluminum material and sodium sulfate in a mass ratio of 1:5, then mix the mixture with water at a solid-liquid mass ratio of 1:10, add three different sizes of zirconia beads with diameters of 5 mm, 10 mm, and 15 mm in a quantity ratio of 3:4:3 for ball milling, and separate the ball milling liquid by suction filtration to obtain ball milling slag and lithium extraction liquid;

[0092] Mix the ball milling slag after ball milling with water at a mass ratio of 1:15, and perform wet screening using a 300-mesh sieve to obtain aluminum slag and nickel-cobalt-manganese powder;

[0093] Prepare a slurry by mixing the aluminum slag and water at a mass ratio of 1:10, then add starch at a mass ratio of starch to aluminum slag of 1:5 for stirring and washing, and perform solid-liquid separation to obtain high-purity aluminum slag and starch water;

[0094] Mix the cathode powder and nickel-cobalt-manganese powder in a mass ratio of 4:1 to obtain a first mixture, add sodium sulfate according to a mass ratio of the first mixture to sodium sulfate of 1:5 to obtain a second mixture, then add starch water according to a mass ratio of the second mixture to starch water of 5:1 for mixing and slurry adjustment. After that, adjust the inclination angle of the pelletizing machine to 30° and the rotation speed to 400 r / min, and pelletize the material by the pelletizing machine, controlling the particle size within 6 mm to obtain cathode pellets;

[0095] Roast the cathode pellets, control the roasting temperature at 450 °C for 6 hours. After mixing the roasted material with water at a mass ratio of 1:10, add three different sizes of zirconia beads with diameters of 5 mm, 10 mm, and 15 mm in a quantity ratio of 3:4:3 for secondary ball milling;

[0096] Add sulfuric acid to the secondary ball milling mixture to adjust the pH to 6.8, then perform filtration separation to obtain secondary ball milling slag and lithium-rich liquid;

[0097] Mix the lithium-rich solution with the lithium-extracted solution and introduce a reducing gas such as carbon dioxide for carbonization treatment and purification to obtain lithium carbonate precipitate. Wash, dehydrate, remove impurities, separate, and dry the lithium carbonate precipitate to obtain lithium carbonate product;

[0098] After subjecting the secondary ball-milled slag to atmospheric pressure leaching, then carry out pressure leaching, control the pressure of pressure leaching at 1.2 - 1.6 MPa and the temperature at 176 - 180 °C to obtain nickel-cobalt-manganese salt and leaching residue.

[0099] Example 2

[0100] The recovery method of the battery cathode material in this example includes the following steps:

[0101] Disassemble the waste ternary lithium-ion battery to obtain the positive electrode sheet and negative electrode sheet inside the battery;

[0102] After subjecting the positive electrode sheet to multi-stage crushing and sorting, obtain positive electrode powder and coarse aluminum material, control the particle size of the coarse aluminum material to be above 300 mesh, and control the aluminum content in the positive electrode powder to be below 2%;

[0103] Mix the coarse aluminum material and sodium sulfate in a mass ratio of 1:3, then mix the mixture with water at a solid-liquid mass ratio of 1:5, add three different sizes of zirconia beads with diameters of 5 mm, 10 mm, and 15 mm in a quantity ratio of 3:4:3 for ball milling, and separate the ball-milled liquid by suction filtration to obtain ball-milled slag and lithium-extracted solution;

[0104] Mix the ball-milled slag after ball milling with water in a mass ratio of 1:10, and carry out wet screening using a 200-mesh sieve to obtain aluminum slag and nickel-cobalt-manganese powder;

[0105] Mix the aluminum slag with water in a mass ratio of 1:5 to form a slurry, then add starch in a mass ratio of starch to aluminum slag of 1:3 for stirring and washing, and carry out solid-liquid separation to obtain high-purity aluminum slag and starch water;

[0106] Mix the positive electrode powder and nickel-cobalt-manganese powder in a mass ratio of 3:1 to obtain a first mixture, add ammonium sulfate in a mass ratio of the first mixture to ammonium sulfate of 1:3 to obtain a second mixture, then add starch water in a mass ratio of the second mixture to starch water of 3:1 for mixing and slurry adjustment, adjust the inclination angle of the pelletizing machine to 15°, adjust the rotation speed to 300 r / min, and pelletize the material by the pelletizing machine, control the particle size within 6 mm to obtain positive electrode pellets;

[0107] Roast the positive electrode pellets, control the roasting temperature at 400 °C, roast for 4 hours, mix the roasted material with water in a mass ratio of 1:5, and then add three different sizes of zirconia beads with diameters of 5 mm, 10 mm, and 15 mm in a quantity ratio of 3:4:3 for secondary ball milling;

[0108] After adding sulfuric acid to the secondary ball-milled mixture to adjust the pH to 7.2, filtration separation is carried out to obtain secondary ball-milled slag and lithium-rich solution;

[0109] Mix the lithium-rich solution with the lithium extraction solution and introduce a reducing gas such as carbon dioxide for carbonization treatment and purification to obtain lithium carbonate precipitate. The lithium carbonate precipitate is washed, dehydrated, impurity-removed, separated, and dried to obtain lithium carbonate product;

[0110] After the secondary ball-milled slag is leached under normal pressure, pressure leaching is carried out. The pressure of the pressure leaching is controlled at 1.2 - 1.6 MPa and the temperature is controlled at 176 - 180 °C to obtain nickel-cobalt-manganese salt and leaching residue.

[0111] Example 3

[0112] The recovery method of the battery cathode material in this example includes the following steps:

[0113] Disassemble the used ternary lithium-ion battery to obtain the positive electrode sheet and negative electrode sheet inside the battery;

[0114] After the positive electrode sheet is subjected to multi-stage crushing and sorting, positive electrode powder and coarse aluminum material are obtained. The particle size of the coarse aluminum material is controlled above 300 mesh, and the aluminum content in the positive electrode powder is controlled below 2%;

[0115] After the coarse aluminum material and sodium sulfate are mixed according to a mass ratio of 1:8, the mixture is mixed with water according to a solid-liquid mass ratio of 1:15, and three different sizes of zirconia beads with diameters of 5 mm, 10 mm, and 15 mm are added according to a quantity ratio of 3:4:3 for ball milling. The ball-milled liquid is separated by suction filtration to obtain ball-milled slag and lithium extraction solution;

[0116] Mix the ball-milled slag after ball milling with water according to a mass ratio of 1:20, and perform wet screening using a 300-mesh sieve to obtain aluminum slag and nickel-cobalt-manganese powder;

[0117] Mix the aluminum slag with water according to a mass ratio of 1:15 to form a slurry, and then add starch according to a mass ratio of starch to aluminum slag of 1:8 for stirring and washing. Solid-liquid separation is carried out to obtain high-purity aluminum slag and starch water;

[0118] Mix the positive electrode powder and nickel-cobalt-manganese powder according to a mass ratio of 5:1 to obtain a first mixture. Add sodium sulfate according to a mass ratio of the first mixture to sodium sulfate of 1:7 to obtain a second mixture. Then, add starch water according to a mass ratio of the second mixture to starch water of 8:1 for mixing and slurry adjustment. Adjust the inclination angle of the pelletizing machine to 45° and the rotation speed to 500 r / min. The material is pelletized by the pelletizing machine, and the particle size is controlled within 6 mm to obtain positive electrode pellets;

[0119] Roast the positive electrode pellets, control the roasting temperature at 500 °C, and roast for 4 hours. After mixing the roasted materials with water at a mass ratio of 1:15, add three different sizes of zirconia beads with diameters of 5 mm, 10 mm, and 15 mm at a quantity ratio of 3:4:3 for secondary ball milling;

[0120] Add sulfuric acid to the secondary ball milling mixture to adjust the pH to 6.5, then filter and separate to obtain secondary ball milling slag and lithium-rich solution;

[0121] Mix the lithium-rich solution with the lithium extraction solution and introduce a reducing gas such as carbon dioxide for carbonization treatment and purification to obtain lithium carbonate precipitate. Wash, dehydrate, remove impurities, separate, and dry the lithium carbonate precipitate to obtain lithium carbonate product;

[0122] After subjecting the secondary ball milling slag to atmospheric pressure leaching, then carry out pressure leaching. Control the pressure leaching pressure at 1.2 - 1.6 MPa and the temperature at 176 - 180 °C to obtain nickel-cobalt-manganese salt and leaching residue.

[0123] Example 4

[0124] The recycling method of the battery positive electrode material in this example includes the following steps:

[0125] Disassemble the waste ternary lithium-ion battery to obtain the positive electrode sheet and negative electrode sheet inside the battery;

[0126] After subjecting the positive electrode sheet to multi-stage crushing and sorting, obtain positive electrode powder and coarse aluminum material. Control the particle size of the coarse aluminum material above 300 mesh, and control the aluminum content in the positive electrode powder below 2%;

[0127] Mix the coarse aluminum material with sodium sulfate at a mass ratio of 1:5, then mix the mixture with water at a solid-liquid mass ratio of 1:10, add three different sizes of zirconia beads with diameters of 5 mm, 10 mm, and 15 mm at a quantity ratio of 3:4:3 for ball milling, and separate the ball milling liquid by suction filtration to obtain ball milling slag and lithium extraction solution;

[0128] Mix the ball milling slag after ball milling with water at a mass ratio of 1:20, and perform wet screening using a 300-mesh sieve to obtain aluminum slag and nickel-cobalt-manganese powder;

[0129] Prepare a slurry by mixing the aluminum slag with water at a mass ratio of 1:10, then add starch at a mass ratio of starch to aluminum slag of 1:5 for stirring and washing, and perform solid-liquid separation to obtain high-purity aluminum slag and starch water;

[0130] Mix the positive electrode powder and nickel-cobalt-manganese powder at a mass ratio of 4:1 to obtain the first mixture, add sodium sulfate at a mass ratio of the first mixture to sodium sulfate of 1:5 to obtain the second mixture, and then add starch water at a mass ratio of the second mixture to starch water of 5:1 for mixing and adjusting the slurry;

[0131] Roast the slurry, control the roasting temperature at 450 °C, and roast for 6 hours. After mixing the roasted material with water at a mass ratio of 1:10, add three different sizes of zirconia beads with diameters of 5 mm, 10 mm, and 15 mm at a quantity ratio of 3:4:3 for secondary ball milling;

[0132] Add sulfuric acid to the secondary ball milling mixture to adjust the pH to 7.5, then filter and separate to obtain secondary ball milling slag and lithium-rich solution;

[0133] Mix the lithium-rich solution with the lithium extraction solution and introduce a reducing gas such as carbon dioxide for carbonization treatment and purification to obtain lithium carbonate precipitate. Wash, dehydrate, remove impurities, separate, and dry the lithium carbonate precipitate to obtain lithium carbonate product;

[0134] After subjecting the secondary ball milling slag to atmospheric pressure leaching, then carry out pressure leaching, control the pressure leaching pressure at 1.2 - 1.6 MPa and the temperature at 176 - 180 °C to obtain nickel-cobalt-manganese salt and leaching residue.

[0135] Comparative Example 1

[0136] This comparative example provides a method for recycling battery cathode materials. Different from Example 1, in this comparative example, two-stage lithium extraction is not used, and wet ball milling is not used for preferential lithium extraction. The specific steps are as follows:

[0137] Disassemble the waste ternary lithium-ion battery to obtain the positive electrode sheet and negative electrode sheet inside the battery;

[0138] After subjecting the positive electrode sheet to multi-stage crushing and sorting, obtain positive electrode powder and coarse aluminum material, control the particle size of the coarse aluminum material above 300 mesh, and control the aluminum content in the positive electrode powder below 2%;

[0139] Mix the coarse aluminum material with water at a mass ratio of 1:10 to form a slurry, then add starch at a mass ratio of starch to aluminum slag of 1:5 for stirring and washing, and perform solid-liquid separation to obtain aluminum slag and starch water;

[0140] Mix the positive electrode powder and sodium sulfate at a mass ratio of 1:5 to obtain a mixture, then add starch water at a mass ratio of the mixture to starch water of 5:1 for mixing and slurry adjustment. Then adjust the inclination angle of the pelletizer to 45 ° and the rotation speed to 500 r / min. The pelletizer spheroidizes and granulates the material, controlling the particle size within 6 mm to obtain positive electrode pellets;

[0141] Roast the positive electrode pellets, control the roasting temperature at 450 °C, and roast for 6 hours. After mixing the roasted material with water at a mass ratio of 1:10, add three different sizes of zirconia beads with diameters of 5 mm, 10 mm, and 15 mm at a quantity ratio of 3:4:3 for ball milling;

[0142] After adding sulfuric acid to the ball-milled mixed solution to adjust the pH to 6.8, filter and separate to obtain ball-milled slag and lithium-rich solution;

[0143] Mix the lithium-rich solution with the lithium extraction solution and introduce reducing gases such as carbon dioxide for carbonization treatment and purification to obtain lithium carbonate precipitate. Wash, dehydrate, remove impurities, separate, and dry the lithium carbonate precipitate to obtain lithium carbonate product.

[0144] After subjecting the ball-milled slag to atmospheric leaching, then carry out pressure leaching. Control the pressure of pressure leaching at 1.2 - 1.6 MPa and the temperature at 176 - 180 °C to obtain nickel-cobalt-manganese salt and leaching residue.

[0145] Comparative Example 2

[0146] This comparative example provides a method for recycling battery cathode materials. Different from Example 1, in this comparative example, two-stage lithium extraction is not used, starch is not used to stir and wash aluminum slag and for pelletizing, but pickling of crude aluminum material is adopted, which specifically includes the following steps:

[0147] Disassemble waste ternary lithium-ion batteries to obtain the cathode and anode sheets inside the batteries;

[0148] After subjecting the cathode sheet to multi-stage crushing and sorting, obtain cathode powder and crude aluminum material. Control the particle size of the crude aluminum material to be above 300 mesh, and control the aluminum content in the cathode powder to be below 2%;

[0149] Mix the crude aluminum material and water in a mass ratio of 1:10 to form a slurry, then add sulfuric acid to adjust the pH to 0.5 - 1 to obtain aluminum slag and washing residue water;

[0150] Mix the cathode powder and sodium sulfate in a mass ratio of 1:5 to obtain a mixture, then mix and adjust the slurry according to the mass ratio of the mixture to the washing residue water of 5:1. Then adjust the inclination angle of the pelletizing machine to 45° and the rotation speed to 500 r / min. Pelletize the material by the pelletizing machine, control the particle size within 6 mm to obtain cathode pellets;

[0151] Roast the cathode pellets, control the roasting temperature at 450 °C and roast for 6 hours. After mixing the roasted material and water in a mass ratio of 1:10, then add three different-sized zirconia beads with diameters of 5 mm, 10 mm, and 15 mm in a quantity ratio of 3:4:3 for ball milling;

[0152] After adding sulfuric acid to the ball-milled mixed solution to adjust the pH to 6.8, filter and separate to obtain ball-milled slag and lithium-rich solution;

[0153] Mix the lithium-rich solution with the lithium extraction solution and introduce reducing gases such as carbon dioxide for carbonization treatment and purification to obtain lithium carbonate precipitate. Wash, dehydrate, remove impurities, separate, and dry the lithium carbonate precipitate to obtain lithium carbonate product.

[0154] After subjecting the ball-milled slag to atmospheric pressure leaching, pressure leaching is then carried out. The pressure of the pressure leaching is controlled at 1.2 - 1.6 MPa and the temperature is controlled at 176 - 180 °C to obtain nickel-cobalt-manganese salts and leaching residues.

[0155] Table 1 shows the lithium recovery rates, the main contents and impurity contents (%) in the lithium carbonate products in the above-mentioned examples and comparative examples.

[0156]

[0157] Among them, the lithium recovery rate = the weight of lithium in the lithium carbonate product / the weight of lithium in the cathode sheet raw material.

[0158] It can be seen from Table 1 that the lithium recovery rate in Example 1 is 98.3%, the lithium recovery rate in Example 2 is 96.8%, the lithium recovery rate in Example 3 is 96.2%, the lithium recovery rate in Example 4 is 95.6%, the lithium recovery rate in Comparative Example 1 is 92%, and the lithium recovery rate in Comparative Example 2 is 85%. By comparison, the lithium recovery rates in the examples are significantly higher than those in the comparative examples. Moreover, the content of Li2CO3 in the examples is higher, and the contents of impurities such as Na and Fe are lower. It can be seen that in the examples of the present invention, through two-stage lithium extraction, starch stirring and washing, and pelletizing, the lithium recovery rate is effectively improved, and the impurity content in the lithium carbonate product is reduced.

[0159] Table 2 shows the main contents and impurity contents (%) in the crude aluminum materials in the above-mentioned examples and comparative examples.

[0160] Al Ni Co Mn Li Total Li content Crude aluminum material 72.38 8.70 6.95 3.03 6.89 20.57

[0161] Among them, the total proportion of Li = the weight of lithium in the crude aluminum material / the weight of lithium in the cathode sheet raw material.

[0162] Table 3 shows the main contents and impurity contents (%) in the aluminum slag in the above-mentioned examples and comparative examples.

[0163]

[0164] As can be seen from Tables 2 and 3, the Al content of the aluminum slag obtained in Example 1 is 99.6%, the Al content of the aluminum slag obtained in Example 2 is 99.5%, the Al content of the aluminum slag obtained in Example 3 is 99.4%, the Al content of the aluminum slag obtained in Example 4 is 99.5%, the Al content of the aluminum slag obtained in Comparative Example 1 is 99.3%, the Al content of the aluminum slag obtained in Comparative Example 2 is 99.1%, and the Al content of the crude aluminum material is 72.38%. By comparison, it can be seen that compared with the Al content in the crude aluminum material, the Al content of the aluminum slag in the examples and comparative examples has been improved, and the Al content of the aluminum slag in the examples is higher than that of the aluminum slag in the comparative examples, and the contents of impurities such as Ni and Co in the aluminum slag in the examples are lower. It can be seen that in the examples of the present invention, through two-stage lithium extraction, starch stirring and washing, and pelletizing, the separation effect of the metal active material and the aluminum foil has been comprehensively improved, the metal active material has been extracted, and high-purity aluminum has been separated.

[0165] Table 4 shows the main content and impurity content (%) in the cobalt-nickel salt products in the above examples and comparative examples

[0166]

[0167] As can be seen from Table 4, the Ni2SO4 content of the cobalt-nickel salt product obtained in Example 1 is 99.6%, the Ni2SO4 content of the cobalt-nickel salt product obtained in Example 2 is 99.5%, the Ni2SO4 content of the cobalt-nickel salt product obtained in Example 3 is 99.6%, the Ni2SO4 content of the cobalt-nickel salt product obtained in Example 4 is 99.6%, the Ni2SO4 content of the cobalt-nickel salt product obtained in Comparative Example 1 is 99.2%, and the Ni2SO4 content of the cobalt-nickel salt product obtained in Comparative Example 2 is 98.9%. By comparison, it can be seen that the Ni2SO4 content of the cobalt-nickel salt product obtained in the examples is higher than that of the cobalt-nickel salt product obtained in the comparative examples; the CoSO4 content of the cobalt-nickel salt product obtained in Example 1 is 99.5%, the CoSO4 content of the cobalt-nickel salt product obtained in Example 2 is 99.6%, the CoSO4 content of the cobalt-nickel salt product obtained in Example 3 is 99.5%, the CoSO4 content of the cobalt-nickel salt product obtained in Example 4 is 99.5%, the CoSO4 content of the cobalt-nickel salt product obtained in Comparative Example 1 is 99.3%, and the CoSO4 content of the cobalt-nickel salt product obtained in Comparative Example 2 is 99.1%. By comparison, it can be seen that the CoSO4 content of the cobalt-nickel salt product obtained in the examples is higher than that of the cobalt-nickel salt product obtained in the comparative examples; and the contents of impurities such as Na and Fe in the cobalt-nickel salt product obtained in the examples are lower. It can be seen that in the examples of the present invention, through two-stage lithium extraction, starch stirring and washing, and pelletizing, the purity of nickel cobalt sulfate has been improved, and the impurity content in nickel cobalt sulfate has been effectively reduced.

[0168] The various technical features described above can be combined arbitrarily. Although not all possible combinations of these technical features are described, any combination of these technical features should be considered to be covered by this specification, as long as such a combination is not contradictory.

[0169] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for recycling a cathode material of a battery, characterized in that, It includes the following steps: Subject the cathode material of the battery to multi-stage crushing and screening, collect the fine materials after each stage of crushing and screening to obtain the cathode powder, and collect the coarse materials after the last stage of crushing and screening to obtain the current collector coarse materials; After mixing and reacting the current collector coarse materials with water, filter to obtain the first filter residue and the first filtrate; Mix and wash the first filter residue with water and starch, and perform solid-liquid separation to obtain the current collector fine materials and starch water; Roast the starch water, the cathode powder, and sulfate, add water for mixing after roasting and then filter to obtain the second filter residue and the second filtrate; Perform carbonization treatment on the second filtrate and the first filtrate to obtain the carbonate precipitate of the first metal material; the first metal material is a lithium material.

2. The recycling method of the battery cathode material according to claim 1, characterized in that After obtaining the first filter residue and the first filtrate, the method specifically includes the following steps: After screening the first filter residue, obtain the residue and the powder; Mix and wash the residue with water and starch, and perform solid-liquid separation to obtain the current collector fine materials and starch water; Roast the starch water, the powder, the cathode powder, and sulfate, add water for mixing after roasting and then filter to obtain the second filter residue and the second filtrate.

3. The recycling method of the battery cathode material according to claim 1, wherein The particle size of the current collector coarse materials does not exceed 3 mm, and the particle size of the cathode powder is less than 200 mesh.

4. The recycling method of the cathode material of the battery according to claim 3, characterized in that, The particle size of the current collector coarse materials does not exceed 0.85 mm, and the particle size of the cathode powder is less than 300 mesh.

5. The recycling method of the cathode material of the battery according to claim 3, characterized in that, The content of the current collector in the cathode powder is 2% or less.

6. The recycling method of the cathode material of the battery according to claim 1, characterized in that, Before obtaining the first filter residue and the first filtrate, mix the current collector coarse materials with water and sodium sulfate and perform ball milling.

7. The recycling method of the cathode material of the battery according to claim 6, characterized in that, The ball milling specifically includes the following steps: Mix the current collector coarse materials and sodium sulfate at a mass ratio of 1:3 to 1:8, then mix and ball mill with water at a solid-liquid mass ratio of 1:5 to 1:15, and filter to obtain the first filter residue and the first filtrate.

8. The recycling method of the cathode material of the battery according to claim 2, characterized in that, After subjecting the first filter residue to wet screening, obtain the residue and the powder.

9. The recycling method of the cathode material of the battery according to claim 8, characterized in that, The wet screening specifically includes the following steps: Mix the first filter residue with water at a mass ratio of 1:10 to 1:20, and perform screening with 200 to 300 mesh. The oversize is the residue, and the undersize is the powder.

10. The recycling method of the cathode material of the battery according to claim 2, characterized in that, The mixing and washing method of the residue with water and starch specifically includes: Make the residue into a slurry with water at a mass ratio of 1:5 to 1:15, then add starch at a mass ratio of starch to the residue of 1:3 to 1:8 for washing, and perform solid-liquid separation to obtain the current collector fine materials and starch water.

11. The recycling method of the cathode material of the battery according to claim 2, characterized in that, Before obtaining the second filter residue and the second filtrate, it includes the following treatment steps: Mix the starch water with the powder, the cathode powder, and sulfate and then roast to obtain the roasted material, and then add water for mixing and perform ball milling on the roasted material to obtain the ball milling mixture; Adjust the pH of the ball milling mixture to the first pH value, and then filter to obtain the second filter residue and the second filtrate.

12. The recycling method of the cathode material of the battery according to claim 11, characterized in that, After mixing the starch water with the powder, the cathode powder, and sulfate, the method further includes: Pelletize the mixture to obtain a cathode pellet, and roast the cathode pellet.

13. The recycling method of the battery cathode material according to claim 12, wherein The pelletization specifically includes the following steps: Mix the positive electrode powder and the powder in a mass ratio of 3:1 to 5:1 to obtain a first mixture, add sulfate to the first mixture in a mass ratio of 1:3 to 1:7 to obtain a second mixture, and then add the starch solution to the second mixture in a mass ratio of 2:1 to 8:1, mix well and adjust the slurry, and then pelletize the material to obtain positive electrode pellets.

14. The recycling method of the battery cathode material according to claim 13, wherein The roasting temperature is 400-500 °C, the roasting time is 4-6 hours, and the mass ratio of the roasted material to water is 1:5 to 1:

15.

15. The recycling method of the battery cathode material according to claim 13, wherein The first pH value is 6.5-7.

5.

16. The recycling method of the battery cathode material according to claim 1 or 2, characterized in that, The specific steps of the carbonization treatment include: Pass carbon dioxide into the first filtrate and the second filtrate to obtain a carbonate precipitate of the first metal material.

17. The recycling method of the battery cathode material according to claim 16, the method further comprising the following steps: Perform wet impurity removal on the second filter residue to obtain a second metal material.

18. The method for recycling the battery positive electrode material according to claim 17, wherein the battery is a lithium-ion battery, and the second metal material is other metal materials in the battery positive electrode material except lithium.

19. The method for recycling the battery positive electrode material according to claim 18, wherein the second metal material is at least one of nickel, cobalt, and manganese.

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