CN116253339B

CN116253339B - Recovery method of ternary lithium ion battery

Info

Publication number: CN116253339B
Application number: CN202310136795.8A
Authority: CN
Inventors: 颜群轩; 谭群英; 陈嘉鑫; 聂蓉
Original assignee: Changsha Jinkai Recycling Technology Co ltd; Hunan Jinkai Recycling Technology Co ltd
Current assignee: Changsha Jinkai Recycling Technology Co ltd; Hunan Jinkai Recycling Technology Co ltd
Priority date: 2023-02-20
Filing date: 2023-02-20
Publication date: 2025-03-07
Anticipated expiration: 2043-02-20
Also published as: CN116253339A

Abstract

The invention provides a recovery method of a ternary lithium ion battery, which belongs to the field of batteries and comprises the steps of crushing the battery, heating and reacting, collecting condensed electrolyte through negative pressure, carrying out primary roasting and secondary roasting on solid materials, filtering to obtain a lithium solution and slag containing nickel cobalt, manganese, copper, iron and aluminum and graphite after leaching with water, removing impurities from the lithium solution, concentrating and crystallizing to obtain battery-grade lithium hydroxide, pulping the slag containing nickel, cobalt, manganese, copper, iron and aluminum and graphite with water, adding acid, adding iron powder into the solution to remove copper, extracting nickel and cobalt with HBL110, extracting with P204, concentrating and crystallizing the solution to obtain refined nickel sulfate, cobalt sulfate or nickel chloride and cobalt chloride, adding sodium chlorate into the extracted raffinate, oxidizing divalent iron into trivalent iron, regulating with alkali, filtering to obtain slag containing iron and manganese solution containing calcium and magnesium, extracting manganese in the manganese solution with C272, back-extracting to obtain manganese sulfate or manganese chloride solution, concentrating and crystallizing to obtain battery-grade manganese sulfate or manganese chloride for the battery.

Description

Recovery method of ternary lithium ion battery

Technical Field

The invention belongs to the field of battery manufacturing, and particularly relates to a recovery method of a ternary lithium ion battery.

Background

The ternary lithium ion battery refers to a secondary lithium ion battery using three nickel cobalt manganese transition metal oxides as a positive electrode material. The method fully combines the good performance of lithium cobaltate circulation, the high specific capacity of lithium nickelate and the high safety and low cost of lithium manganate, and synthesizes the composite lithium intercalation oxide of nickel with various elements (such as cobalt and manganese) on the molecular level through the methods of mixing, doping, coating and surface modification. It is a rechargeable lithium ion battery that has been widely studied and used.

The life of a lithium ion battery refers to the decomposition of the battery capacity to 70% of the nominal capacity after a period of use, and can be considered as the end of the life. In industry, cycle life is typically calculated from the number of cycles when a lithium ion battery is full and discharged. During use, irreversible electrochemical reactions will occur within the lithium ion battery, which will lead to reduced capacity, such as electrolyte breakdown, deactivation of active materials, structural collapse of the positive and negative electrodes, and a reduction in the number of internal and external lithium ions. The theoretical lifetime of a ternary lithium ion battery is about 800 cycles, which is the average lifetime in a commercial rechargeable lithium ion battery. The used waste ternary lithium ion battery contains various harmful substances such as organic solvents, heavy metals and toxic gases, and if the waste ternary lithium ion battery is not recycled, serious environmental pollution can be caused. The method has the most valuable in the recovery process of the waste ternary lithium ion battery, namely, the recovery of metals such as nickel, cobalt, manganese, copper, iron, aluminum and the like in the lithium ion battery. The prior art can realize the recovery of metals, but the purity of the obtained final lithium product is not high.

Disclosure of Invention

The invention aims to provide a recovery method of a ternary lithium ion battery, which utilizes the characteristics that iron and aluminum of the battery are reduced after being ground into powder, and graphite is combusted under certain conditions to generate carbon monoxide which is reduced, and the ternary lithium ion battery anode material is reduced in the roasting process, so that lithium can be selectively leached out by water at the front end, the leaching rate of the process lithium is up to 98.5%, and meanwhile, no reducing gas such as additional hydrogen is needed. The pH value of the slag containing nickel cobalt manganese copper iron aluminum and graphite is regulated to 1.0-2.0 by sulfuric acid or hydrochloric acid, the leaching rate of nickel cobalt manganese can reach 99.5%, and the leaching rate of copper iron aluminum is less than 10%, so that the nickel cobalt manganese and copper iron aluminum are effectively separated by the method.

The invention is realized by the following technical scheme that the recovery method of the ternary lithium ion battery comprises the following steps:

step 1, crushing a ternary lithium ion battery in an inert protective atmosphere to obtain crushed materials;

step2, placing the crushed materials in a closed environment for heating reaction, and collecting condensed electrolyte through negative pressure to obtain solid materials;

Step 3, ball milling the solid materials, and sieving the solid materials with a sieve of 20-500 meshes;

step 4, performing primary roasting and secondary roasting on the solid material in the step 3;

Step 5, leaching with water, and filtering to obtain a lithium solution and slag containing nickel cobalt, manganese, copper, iron, aluminum and graphite;

Step 6, removing impurities from the lithium solution obtained in the step 5 by using resin or a film to obtain a pure lithium hydroxide solution, and concentrating and crystallizing the lithium hydroxide to obtain a battery grade lithium hydroxide monohydrate product;

step 7, adding water into the slag containing nickel cobalt, manganese, copper, iron and aluminum and graphite for pulping, adding sulfuric acid or hydrochloric acid, regulating the pH value to be stable at 1.0-2.0 for 20-40min, and filtering to obtain graphite slag and solution;

step 8, adding reduced iron powder into the solution to remove copper, and filtering to obtain sponge copper and a solution after copper removal;

Step 9, extracting nickel and cobalt in the copper-removed solution by using an HBL110 extractant, and then back-extracting to obtain a nickel and cobalt sulfate solution or a nickel and cobalt chloride solution;

step 10, extracting nickel cobalt sulfate solution or nickel cobalt chloride solution by using P204, and concentrating and crystallizing the back extracted nickel sulfate, cobalt sulfate or nickel chloride and cobalt chloride solution to obtain refined nickel sulfate, cobalt sulfate or nickel chloride and cobalt chloride;

step 11, adding sodium chlorate into the raffinate extracted in the step 9, oxidizing ferrous iron in the raffinate into ferric iron, then adjusting the pH value of the raffinate extracted in the step 9 to 4.0-5.0 by using sodium hydroxide, sodium carbonate or calcium carbonate, and filtering to obtain slag containing iron and lithium and manganese solution containing calcium and magnesium;

And 12, extracting manganese in the manganese solution by using a C272 extractant, back extracting to obtain manganese sulfate or manganese chloride solution, and concentrating and crystallizing to obtain battery-grade manganese sulfate or battery-grade manganese chloride.

Preferably, in the step 1, the ternary lithium ion battery is made of LiNi _xCo_yMn_zO₂ as a positive electrode material, wherein x is more than or equal to 0 and less than or equal to 1, 0.ltoreq.y.ltoreq.y.ltoreq. 1, 0.ltoreq.z.ltoreq.1, x+y+z=1.

Preferably, in step 2, the reaction temperature is 100-250 ℃.

Preferably, in the step 4, the primary roasting is carried out for 1-3 hours at the temperature of 300-400 ℃ in an inert protective atmosphere, and the secondary roasting is carried out for 20-60 minutes at the temperature of 750-1000 ℃ in an air atmosphere.

Preferably, in the step 7, water is added into slag containing nickel cobalt, manganese copper, iron and aluminum and graphite for pulping, and the solid-liquid ratio is 1:3-1:6.

Preferably, in the step 8, reduced iron powder is added into the solution, wherein the addition amount of the iron powder is 1.0-1.3 times of the total amount of copper in the solution, and the copper content in the solution after copper removal is not more than 0.005g/L.

Wherein, the HBL110 extractant provides a solution for selectively and directly extracting nickel from nickel-containing acidic solution (laterite-nickel ore pickle liquor, nickel-containing electroplating sludge pickle liquor, nickel-containing spent catalyst pickle liquor and the like). In the process of extracting, separating and purifying the acidic solution containing nickel, the HBL110 can selectively and directly extract nickel, basically does not extract Fe, al, cr, zn, mn, mg, ca and the like, realizes the separation of Ni and the impurities, replaces four procedures of 'precipitating Fe, deeply removing Fe and Al by hydrolysis, precipitating Ni and Co and acid dissolution' in the traditional nickel wet treatment process with one procedure of 'directly extracting Ni', greatly reduces the process flow, obviously reduces the cost, greatly improves the yield of nickel, and simultaneously realizes the comprehensive recycling of valuable metal resources.

The physical characteristics of the HBL110 extractant comprise brown transparent liquid in appearance, specific gravity (25 ℃) of 0.97+/-0.005 g/cm ³, flash point of >70 ℃, larger nickel load of performance parameter of more than or equal to 7g/L, extraction kinetics of more than or equal to 95% (5 min), extraction phase separation of less than or equal to 5min, stripping kinetics of more than or equal to 90% (5 min) and stripping phase separation of less than or equal to 5min.

Wherein p204 is named as di (2-ethylhexyl) phosphate, diisooctyl phosphate and dioctyl phosphate, and the national CAS registry number is 298-07-7, and is colorless, transparent and sticky liquid. Freezing point-60 ℃, relative density 0.973 (25/25 ℃), refractive index 1.4420 (25 ℃) and boiling point 209 ℃ (1.33 kPa).

Wherein the main component of the C272 extractant is di (2, 4-trimethyl amyl) phosphonic acid. Typical physical properties of the technical product are a content of >85%, a colorless or slightly amber color, a density (24 ℃) of 0.92g/cm ³, a viscosity (25 ℃) of 0.142pa.s, (50 ℃) of 0.037pa.s, a freezing point of-32 ℃, a flash point of 108 ℃, and a solubility in water (ph=2.6) of 16ppm.

The invention has the following beneficial effects:

1. By utilizing the characteristics that iron and aluminum of the battery are reduced after being ground into powder and graphite is reduced by burning under certain conditions to generate carbon monoxide, the ternary lithium ion battery anode material is reduced in the roasting process, so that lithium can be selectively leached out by water at the front end, the leaching rate of the lithium is up to 98.5%, and meanwhile, no reducing gas such as hydrogen and the like is added.

2. The pH value of the slag containing nickel cobalt manganese copper iron aluminum and graphite is regulated to 1.0-2.0 by sulfuric acid or hydrochloric acid, the leaching rate of nickel cobalt manganese can reach 99.5%, and the leaching rate of copper iron aluminum is less than 10%, so that the nickel cobalt manganese and copper iron aluminum are effectively separated by the method.

3. Under the condition of no iron, aluminum, calcium and magnesium, the HBL110 extractant is directly used for extracting nickel and cobalt, thereby reducing the loss of nickel and cobalt and providing the recovery rate of nickel and cobalt.

4. And extracting manganese in the manganese solution by using a C272 extractant, and directly concentrating and crystallizing the manganese sulfate or the manganese chloride obtained after back extraction without removing impurities to obtain the battery-grade manganese sulfate or the battery-grade manganese chloride.

5. The lithium hydroxide solution obtained after reduction can be used for preparing battery grade lithium hydroxide monohydrate after impurity removal through resin or a membrane.

Detailed Description

The features and advantages of the present application will become more apparent and clear from the following detailed description of the application.

In the description of the present application, it should be noted that the directions or positional relationships indicated by the terms "upper", "lower", "inner", "outer", "front", "rear", "left" and "right", etc. are directions or positional relationships based on the operation state of the present application are merely for convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements to be referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present application. Furthermore, the terms "first," "second," "third," and "fourth" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

The technical solutions of the embodiments of the present application will be clearly and completely described below in conjunction with the embodiments of the present application, and it is apparent that the described embodiments are only some embodiments of the present application, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to fall within the scope of the application.

Embodiment 1, the invention is realized by the following technical scheme that the recovery method of the ternary lithium ion battery comprises the following steps:

Step 1, crushing a ternary lithium ion battery in an inert protective atmosphere to obtain a crushed material, wherein the ternary lithium ion battery is made of a positive electrode material LiNi _xCo_yMn_zO₂ (x is more than or equal to 0 and less than or equal to 1, y is more than or equal to 0 and less than or equal to 1, z is more than or equal to 0 and less than or equal to 1, and x+y+z=1);

Step 2, placing the crushed materials in a closed environment for heating reaction, and collecting condensed electrolyte through negative pressure to obtain solid materials, wherein the reaction temperature is 250 ℃;

step 3, ball milling the solid materials, and sieving with a 500-mesh sieve;

Step 4, roasting for 3 hours at 400 ℃ in a first stage in an inert protective atmosphere, and roasting for 60 minutes at 1000 ℃ in a second stage in an air atmosphere;

and 6, removing impurities from the lithium solution obtained in the step 5 by using resin or a film to obtain a pure lithium hydroxide solution, and concentrating and crystallizing the lithium hydroxide to obtain a battery grade lithium hydroxide monohydrate product.

And 7, adding water into the slag containing nickel, cobalt, manganese, copper, iron and aluminum and graphite for pulping, wherein the solid-to-liquid ratio is 1:6, adding sulfuric acid or hydrochloric acid, regulating the pH value to be stable at 2.0 for 40min, and filtering to obtain graphite slag and solution.

Step 8, adding reduced iron powder into the solution, wherein the addition amount of the iron powder is 1.3 times of the total amount of copper in the solution, the copper content in the solution after copper removal is not more than 0.005g/L, and filtering to obtain sponge copper and the solution after copper removal;

and 10, extracting the nickel-cobalt sulfate solution or the nickel-cobalt chloride solution by using P204, and concentrating and crystallizing the back-extracted nickel sulfate, cobalt sulfate or nickel chloride and cobalt chloride solution to obtain refined nickel sulfate, cobalt sulfate or nickel chloride and cobalt chloride.

And 11, adding sodium chlorate into the raffinate extracted in the step 9, oxidizing ferrous iron in the raffinate into ferric iron, then adjusting the pH value of the raffinate extracted in the step 9 to 5.0 by using sodium hydroxide, sodium carbonate or calcium carbonate, and filtering to obtain slag containing iron and lithium and manganese solution containing calcium and magnesium.

Embodiment 2 the invention is realized by the following technical scheme that the recovery method of the ternary lithium ion battery comprises the following steps:

Step 2, placing the crushed materials in a closed environment for heating reaction, and collecting condensed electrolyte through negative pressure to obtain solid materials, wherein the reaction temperature is 100 ℃;

step3, ball milling the solid materials, and sieving the solid materials with a 20-mesh sieve;

step 4, roasting for 1h at 300 ℃ in a first stage in an inert protective atmosphere, and roasting for 20min at 750 ℃ in a second stage in an air atmosphere;

And 7, adding water into the slag containing nickel, cobalt, manganese, copper, iron and aluminum and graphite for pulping, wherein the solid-to-liquid ratio is 1:3, adding sulfuric acid or hydrochloric acid, regulating the pH value to be stable at 1.0 for 20min, and filtering to obtain graphite slag and solution.

Step 8, adding reduced iron powder into the solution, wherein the addition amount of the iron powder is 1.0 time of the total amount of copper in the solution, the copper content in the solution after copper removal is not more than 0.005g/L, and filtering to obtain sponge copper and the solution after copper removal;

And 11, adding sodium chlorate into the raffinate extracted in the step 9, oxidizing ferrous iron in the raffinate into ferric iron, then adjusting the pH value of the raffinate extracted in the step 9 to 4.0 by using sodium hydroxide, sodium carbonate or calcium carbonate, and filtering to obtain slag containing iron and lithium and manganese solution containing calcium and magnesium.

Embodiment 3 the invention is realized by the following technical scheme that the recovery method of the ternary lithium ion battery comprises the following steps:

Step 2, placing the crushed materials in a closed environment for heating reaction, and collecting condensed electrolyte through negative pressure to obtain solid materials, wherein the reaction temperature is 200 ℃;

Step 3, ball milling the solid materials, and sieving the solid materials with a 300-mesh sieve;

Step 4, roasting for 2 hours at the temperature of 350 ℃ in a first stage in an inert protective atmosphere, and roasting for 40 minutes at the temperature of 800 ℃ in a second stage in an air atmosphere;

And 7, adding water into the slag containing nickel, cobalt, manganese, copper, iron and aluminum and graphite for pulping, wherein the solid-to-liquid ratio is 1:5, adding sulfuric acid or hydrochloric acid, regulating the pH value to be stable at 1.5 for 30min, and filtering to obtain graphite slag and solution.

Step 8, adding reduced iron powder into the solution, wherein the addition amount of the iron powder is 1.2 times of the total amount of copper in the solution, the copper content in the solution after copper removal is not more than 0.005g/L, and filtering to obtain sponge copper and the solution after copper removal;

And 11, adding sodium chlorate into the raffinate extracted in the step 9, oxidizing ferrous iron in the raffinate into ferric iron, then adjusting the pH value of the raffinate extracted in the step 9 to 4.5 by using sodium hydroxide, sodium carbonate or calcium carbonate, and filtering to obtain slag containing iron and lithium and manganese solution containing calcium and magnesium.

The application has been described in detail in connection with the specific embodiments and exemplary examples thereof, but such description is not to be construed as limiting the application. It will be understood by those skilled in the art that various equivalent substitutions, modifications or improvements may be made to the technical solution of the present application and its embodiments without departing from the spirit and scope of the present application, and these fall within the scope of the present application. The scope of the application is defined by the appended claims.

Claims

1. A method for recycling ternary lithium-ion batteries, characterized in that it comprises the following steps:

Step 1: crushing the ternary lithium-ion battery in an inert protective atmosphere to obtain crushed materials;

Step 2: placing the crushed material in a closed environment for heating and reaction, and collecting the condensed electrolyte by negative pressure to obtain a solid material;

Step 3: After ball milling, the solid material is passed through a 20-500 mesh sieve;

Step 4: The solid material of step 3 is subjected to primary and secondary calcination, wherein the primary calcination is carried out at 300-400° C. for 1-3 h in an inert protective atmosphere, and the secondary calcination is carried out at 750-1000° C. for 20-60 min in an air atmosphere;

Step 5: leaching with water and filtering to obtain a lithium solution and slag containing nickel, cobalt, manganese, copper, iron, aluminum and graphite;

Step 6: The lithium solution obtained in step 5 is purified by resin or membrane to obtain a pure lithium hydroxide solution, and the lithium hydroxide is concentrated and crystallized to obtain a battery-grade lithium hydroxide monohydrate product;

Step 7: Add water to the slag containing nickel, cobalt, manganese, copper, iron, aluminum and graphite to make a slurry, add sulfuric acid or hydrochloric acid, adjust the pH value to be stable at 1.0-2.0 for 20-40 minutes, and filter to obtain graphite slag and solution;

Step 8: Add reduced iron powder to the solution to remove copper, and filter to obtain sponge copper and a solution after copper removal;

Step 9: extracting nickel and cobalt in the solution after copper removal with HBL110 extractant, and then stripping to obtain nickel cobalt sulfate solution or nickel cobalt chloride solution;

Step 10: extracting the nickel cobalt sulfate solution or the nickel cobalt chloride solution with P204, and then stripping the nickel sulfate, cobalt sulfate or nickel chloride, cobalt chloride solution, and concentrating and crystallizing the solution to obtain refined nickel sulfate, cobalt sulfate or nickel chloride, cobalt chloride;

Step 11: adding sodium chlorate to the extract residue after extraction in step 9 to oxidize the divalent iron in the extract residue to trivalent iron, and then adjusting the pH value of the extract residue after extraction in step 9 to 4.0-5.0 with sodium hydroxide, sodium carbonate or calcium carbonate, and filtering to obtain iron-lithium-containing slag and calcium-magnesium-containing manganese solution;

Step 12: extracting manganese from the manganese solution with C272 extractant, stripping to obtain manganese sulfate or manganese chloride solution, concentrating and crystallizing to obtain battery-grade manganese sulfate or battery-grade manganese chloride.

2. The method for recycling a ternary lithium-ion battery according to claim 1, characterized in that: in step 1, the positive electrode material of the ternary lithium-ion battery is LiNi _x Co _y Mn _z O ₂ , wherein 0≤x≤1, 0≤y≤1, 0≤z≤1, x+y+z＝1.

3. The method for recycling a ternary lithium-ion battery according to claim 1, characterized in that: in step 2, the reaction temperature is 100-250°C.

4. The method for recycling a ternary lithium-ion battery according to claim 1, characterized in that: in step 7, the slag containing nickel, cobalt, manganese, copper, iron, aluminum and graphite is slurried with water, and the solid-liquid ratio is 1:3-1:6.

5. The method for recovering a ternary lithium-ion battery according to claim 1, characterized in that: in step 8, reduced iron powder is added to the solution, the amount of iron powder added is 1.0-1.3 times the total amount of copper in the solution, and the copper content in the solution after copper removal is not more than 0.005 g/L.