Method for recycling nickel cobalt lithium manganate material of lithium battery by using dry method

Abstract

The invention relates to the technical field of lithium battery positive electrode materials, in particular to a method for recycling a lithium battery nickel cobalt lithium manganate material through a dry method. The method comprises the following steps: 1, crushing a used lithium battery to obtain a positive electrode material and other wastes; 2, the crushed positive electrode material is subjected to high-temperature roasting, the roasting temperature is 800 DEG C, and the roasting time is 1-3 hours; 3, cooling the roasted positive electrode material, and then carrying out mechanical grinding until the grinding particle size is less than 100 meshes; 4, the ground positive electrode material is subjected to chemical leaching, a proper amount of a reducing agent is added into leachate, the reducing agent is an alcohol, amine or thiol compound, the leaching temperature ranges from 80 DEG C to 120 DEG C, and the leaching time ranges from 1 h to 3 h; 5, the leached solution is subjected to solid-liquid separation, and a solution containing metal ions is obtained; 6, adding a proper amount of precipitant into the solution containing the metal ions; and 7, carrying out solid-liquid separation on the precipitated solid and liquid to obtain the nickel cobalt lithium manganate material.

Description

Technical Field

[0001] The present invention relates to the technical field of lithium battery positive electrode materials, and in particular to a method for recycling lithium nickel cobalt manganese oxide materials of lithium batteries by dry method. Background Art

[0002] With the development of science and technology, lithium batteries have been widely used in various fields, such as mobile phones and electric vehicles. In the use of lithium batteries, nickel cobalt manganese oxide cathode materials are key components, and their performance and recycling are of great significance to improving the efficiency and reducing the cost of lithium batteries. However, most of the existing recycling methods are wet recycling, which requires the use of a large amount of organic solvents and water, which not only has low recycling efficiency, but also has a great impact on the environment. Summary of the invention

[0003] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a method for recycling lithium nickel cobalt manganese oxide materials of lithium batteries using a dry method.

[0004] The technical solution of the present invention is:

[0005] A method for recycling lithium nickel cobalt manganese oxide materials of lithium batteries by dry method, comprising the following steps:

[0006] Step 1: crush the used lithium batteries to obtain positive electrode materials and other waste;

[0007] Step 2: calcining the crushed positive electrode material at a high temperature of 500-800°C for 1-3 hours;

[0008] Step 3: The calcined positive electrode material is cooled and then mechanically ground to a particle size of less than 100 mesh;

[0009] Step 4: The ground positive electrode material is chemically leached, and an appropriate amount of reducing agent is added to the leaching solution. The reducing agent is an alcohol, amine or thiol compound, and the leaching temperature is 80-120° C. and the leaching time is 1-3 hours;

[0010] Step 5: The leached solution is subjected to solid-liquid separation to obtain a solution containing metal ions;

[0011] Step 6: Add an appropriate amount of precipitant to the solution containing metal ions, the precipitant is hydroxide or carbonate, the precipitation temperature is 40-80°C, and the precipitation time is 1-3 hours;

[0012] Step 7: The solid-liquid separation after precipitation is carried out to obtain lithium nickel cobalt manganese oxide material.

[0013] Preferably, in step 2, the lithium source of the lithium battery includes lithium carbonate, lithium hydroxide, lithium oxalate, lithium acetate, lithium chloride or lithium phosphate; the iron source includes ferrous oxalate and ferrous acetate; and the phosphorus source includes diammonium dihydrogen phosphate and diammonium hydrogen phosphate.

[0014] Preferably, in the step 2, the powder of the lithium battery positive electrode recycling material is the powder obtained by processing the failed pole pieces made of the lithium battery positive electrode material, and is the powder obtained by processing the leftover materials of the lithium battery positive electrode material.

[0015] Preferably, in step three, the ratio of the amount of lithium in the lithium battery solution to the amount of transition metal in the lithium battery positive electrode recovery material is 20:1 to 1:5; the time for hydrothermal lithium replenishment is 1 to 6 hours; and the temperature range for hydrothermal lithium replenishment is 150 to 250°C.

[0016] Preferably, in step 4, the selection and addition amount of the precipitant should be determined according to the specific metal ion type and precipitation requirements.

[0017] Preferably, in step 5, if the precipitation temperature is too low, it will affect the precipitation effect, and if it is too high, it will cause precipitation of other components in the solution; if the precipitation time is too short, the precipitation will be incomplete, and if it is too long, the precipitation will be excessive, resulting in the loss of other useful components in the solution.

[0018] Preferably, in step five, the solid precipitate is separated from the solution by filtering or centrifuging to facilitate subsequent washing and drying operations; at the same time, care should be taken to avoid losses caused by re-dissolution of the precipitant and the product material.

[0019] Preferably, in the step five, the coarse powder of the lithium battery positive electrode recycling material is crushed and screened to obtain the fine powder of the lithium battery positive electrode recycling material.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] By crushing and high-temperature calcining the used lithium batteries, and cooling, grinding and chemically leaching the calcined positive electrode materials, the dry recycling and reuse of nickel-cobalt-manganese oxide materials is achieved. This method has the advantages of simple operation, environmental protection, high efficiency and low cost. DETAILED DESCRIPTION

[0022] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0023] Example 1

[0024] This embodiment provides a method for recycling lithium nickel cobalt manganese oxide materials of lithium batteries by dry method, comprising the following steps:

[0025] Step 1: crush the used lithium batteries to obtain positive electrode materials and other waste;

[0026] Step 2: calcining the crushed positive electrode material at a high temperature of 500-800°C for 1-3 hours;

[0027] Step 3: The calcined positive electrode material is cooled and then mechanically ground to a particle size of less than 100 mesh;

[0028] Step 4: The ground positive electrode material is chemically leached, and an appropriate amount of reducing agent is added to the leaching solution. The reducing agent is an alcohol, amine or thiol compound, and the leaching temperature is 80-120° C. and the leaching time is 1-3 hours;

[0029] Step 5: The leached solution is subjected to solid-liquid separation to obtain a solution containing metal ions;

[0030] Step 6: Add an appropriate amount of precipitant to the solution containing metal ions, the precipitant is hydroxide or carbonate, the precipitation temperature is 40-80°C, and the precipitation time is 1-3 hours;

[0031] Step 7: The solid-liquid separation after precipitation is carried out to obtain lithium nickel cobalt manganese oxide material.

[0032] Preferably, in step 2, the lithium source of the lithium battery includes lithium carbonate, lithium hydroxide, lithium oxalate, lithium acetate, lithium chloride or lithium phosphate; the iron source includes ferrous oxalate and ferrous acetate; and the phosphorus source includes diammonium dihydrogen phosphate and diammonium hydrogen phosphate.

[0033] Preferably, in the step 2, the powder of the lithium battery positive electrode recycling material is the powder obtained by processing the failed pole pieces made of the lithium battery positive electrode material, and is the powder obtained by processing the leftover materials of the lithium battery positive electrode material.

[0034] Preferably, in step three, the ratio of the amount of lithium in the lithium battery solution to the amount of transition metal in the lithium battery positive electrode recovery material is 20:1 to 1:5; the time for hydrothermal lithium replenishment is 1 to 6 hours; and the temperature range for hydrothermal lithium replenishment is 150 to 250°C.

[0035] Preferably, in step 4, the selection and addition amount of the precipitant should be determined according to the specific metal ion type and precipitation requirements.

[0036] Preferably, in step 5, if the precipitation temperature is too low, it will affect the precipitation effect, and if it is too high, it will cause precipitation of other components in the solution; if the precipitation time is too short, the precipitation will be incomplete, and if it is too long, the precipitation will be excessive, resulting in the loss of other useful components in the solution.

[0037] Preferably, in step five, the solid precipitate is separated from the solution by filtering or centrifuging to facilitate subsequent washing and drying operations; at the same time, care should be taken to avoid losses caused by re-dissolution of the precipitant and the product material.

[0038] Preferably, in the step five, the coarse powder of the lithium battery positive electrode recycling material is crushed and screened to obtain the fine powder of the lithium battery positive electrode recycling material.

[0039] Embodiment 1:

[0040] The used lithium batteries are crushed to obtain positive electrode materials and other wastes. The crushed positive electrode materials are placed in a high-temperature furnace for high-temperature roasting at a temperature of 600°C for 2 hours. The roasted positive electrode material is cooled and then mechanically ground to a particle size of less than 100 mesh. An appropriate amount of reducing agent ethanol is added to the ground positive electrode material, and the leaching temperature is 90°C for 2 hours. The leached solution is solid-liquid separated to obtain a solution containing metal ions. An appropriate amount of hydroxide precipitant sodium hydroxide is added to the solution containing metal ions, and the precipitation temperature is 60°C for 2 hours. The solid-liquid separation after precipitation is performed to obtain nickel cobalt manganese oxide lithium material.

[0041] Embodiment 2:

[0042] The used lithium batteries are crushed to obtain positive electrode materials and other wastes. The crushed positive electrode materials are placed in a high-temperature furnace for high-temperature calcination at a temperature of 700°C for 3 hours. The calcined positive electrode material is cooled and then mechanically ground to a particle size of less than 100 mesh. An appropriate amount of reducing agent diglycolamine is added to the ground positive electrode material, the leaching temperature is 100°C, and the leaching time is 3 hours. The leached solution is solid-liquid separated to obtain a solution containing metal ions. An appropriate amount of carbonate precipitant sodium carbonate is added to the solution containing metal ions, the precipitation temperature is 50°C, and the precipitation time is 3 hours. The solid-liquid separation after precipitation is performed to obtain nickel cobalt manganese oxide lithium material.

[0043] Embodiment three:

[0044] The used lithium batteries are crushed to obtain positive electrode materials and other wastes. The crushed positive electrode materials are placed in a high-temperature furnace for high-temperature calcination at a temperature of 800°C for 1 hour. The calcined positive electrode material is cooled and then mechanically ground to a particle size of less than 100 mesh. An appropriate amount of reducing agent dimethyl mercaptan is added to the ground positive electrode material, the leaching temperature is 120°C, and the leaching time is 1 hour. The leached solution is solid-liquid separated to obtain a solution containing metal ions. An appropriate amount of hydroxide precipitant potassium hydroxide is added to the solution containing metal ions, the precipitation temperature is 40°C, and the precipitation time is 1 hour. The solid-liquid separation after precipitation is performed to obtain nickel cobalt manganese oxide lithium material.

Claims

1. A method for recovering lithium nickel cobalt manganese oxide materials of lithium batteries by dry method, characterized in that: The steps include: Step 1: crush the used lithium batteries to obtain positive electrode materials and other waste; Step 2: calcining the crushed positive electrode material at a high temperature of 500-800°C for 1-3 hours; Step 3: The calcined positive electrode material is cooled and then mechanically ground to a particle size of less than 100 mesh; Step 4: The ground positive electrode material is chemically leached, and an appropriate amount of reducing agent is added to the leaching solution. The reducing agent is an alcohol, amine or thiol compound, and the leaching temperature is 80-120° C. and the leaching time is 1-3 hours; Step 5: The leached solution is subjected to solid-liquid separation to obtain a solution containing metal ions; Step 6: Add an appropriate amount of precipitant to the solution containing metal ions, the precipitant is hydroxide or carbonate, the precipitation temperature is 40-80°C, and the precipitation time is 1-3 hours; Step 7: The solid-liquid separation after precipitation is carried out to obtain lithium nickel cobalt manganese oxide material.

2. The method for recovering lithium nickel cobalt manganese oxide materials of lithium batteries by dry method according to claim 1, characterized in that: In the step 2, the lithium source of the lithium battery includes lithium carbonate, lithium hydroxide, lithium oxalate, lithium acetate, lithium chloride or lithium phosphate; the iron source includes ferrous oxalate and ferrous acetate; and the phosphorus source includes diammonium dihydrogen phosphate and diammonium hydrogen phosphate.

3. The method for recovering lithium nickel cobalt manganese oxide materials of lithium batteries by dry method according to claim 1, characterized in that: In the step 2, the powder of the lithium battery positive electrode recycling material is the powder obtained by processing the pole pieces made of lithium battery positive electrode materials after failure, and is the powder obtained by processing the scraps of lithium battery positive electrode materials.

4. The method for recovering lithium nickel cobalt manganese oxide materials of lithium batteries by dry method according to claim 1, characterized in that: In the step three, the ratio of the amount of lithium in the lithium battery solution to the amount of transition metal in the lithium battery positive electrode recovery material is 20:1 to 1:5; the time for hydrothermal lithium replenishment is 1 to 6 hours; and the temperature range of hydrothermal lithium replenishment is 150 to 250°C.

5. The method for recovering lithium nickel cobalt manganese oxide materials of lithium batteries by dry method according to claim 1, characterized in that: In the step 4, the selection and addition amount of the precipitant shall be determined according to the specific metal ion type and precipitation requirements.

6. The method for recovering lithium nickel cobalt manganese oxide materials of lithium batteries by dry method according to claim 1, characterized in that: In the step 5, if the precipitation temperature is too low, it will affect the precipitation effect, and if it is too high, it will cause precipitation of other components in the solution; if the precipitation time is too short, the precipitation will be incomplete, and if it is too long, the precipitation will be excessive, resulting in the loss of other useful components in the solution.

7. The method for recovering lithium nickel cobalt manganese oxide materials of lithium batteries by dry method according to claim 1, characterized in that: In the step 5, the solid precipitate is separated from the solution by filtering and centrifuging to facilitate subsequent washing and drying operations; at the same time, care should be taken to avoid losses caused by the re-dissolution of the precipitant and the product material.

8. The method for recovering lithium nickel cobalt manganese oxide materials of lithium batteries by dry method according to claim 1, characterized in that: In the step five, the coarse powder of the lithium battery positive electrode recovery material is crushed and screened to obtain the fine powder of the lithium battery positive electrode recovery material.