阅读说明：本技术 一种废旧钴酸锂电池再生前驱体材料的制备方法 (Preparation method of regenerated precursor material of waste lithium cobaltate battery ) 是由 欧星 萧厚桂 刘赟 张宝 明磊 于 2021-08-23 设计创作，主要内容包括：一种废旧钴酸锂电池再生前驱体材料的制备方法。本发明包括以下步骤：(1)废旧锂离子电池采用氯化钠溶液进行放电,拆解,将正极片在碱液中进行浸泡,过滤得到黑色粉末；(2)将所得的黑色粉末在保护气气氛下进行还原焙烧,去除杂质；(3)将黑色粉溶解于酸性溶液中,调节pH得到较为纯的含钴和锂的溶液。(4)测得钴和锂离子的浓度后,向溶液中加入相应的镍源,锰源,硼源与铝源；(5)向混合溶液中加入沉淀剂与络合剂,调节pH,进行共沉淀反应,将所得的产品洗涤干燥,得到前驱体。根据本发明提供的方法,不仅有效地减轻废旧锂离子电池所产生的污染,且能将其中废旧钴酸锂材料回收再生新型改性前驱体材料,该前驱体材料具有优异的形貌与尺寸。(A preparation method of a regenerated precursor material of a waste lithium cobaltate battery. The invention comprises the following steps: (1) discharging the waste lithium ion battery by adopting a sodium chloride solution, disassembling, soaking the positive plate in an alkali liquor, and filtering to obtain black powder; (2) carrying out reduction roasting on the obtained black powder in a protective gas atmosphere to remove impurities; (3) dissolving black powder in an acid solution, and adjusting the pH value to obtain a relatively pure solution containing cobalt and lithium. (4) After the concentration of cobalt and lithium ions is measured, adding corresponding nickel source, manganese source, boron source and aluminum source into the solution; (5) and adding a precipitator and a complexing agent into the mixed solution, adjusting the pH value, carrying out coprecipitation reaction, washing and drying the obtained product, and thus obtaining the precursor. According to the method provided by the invention, the pollution generated by the waste lithium ion battery is effectively reduced, and the waste lithium cobaltate material can be recycled to regenerate a novel modified precursor material, and the precursor material has excellent appearance and size.)

1. A preparation method of a regenerated precursor material of a waste lithium cobaltate battery is characterized by comprising the following steps:

(1) discharging the waste lithium ion battery by adopting a sodium chloride solution, then disassembling, soaking the positive plate in an alkali liquor, and filtering to obtain black powder;

(2) carrying out reduction roasting on the obtained powder in a reducing atmosphere to remove impurities;

(3) the resulting black powder was dissolved in an acidic solution and the pH was adjusted to obtain a relatively pure solution containing cobalt and lithium.

(4) After the concentration of cobalt and lithium ions is measured, adding corresponding nickel source, manganese source, boron source and aluminum source into the solution from the outside;

(5) and adding a precipitator and a complexing agent into the prepared mixed solution, adjusting the pH value, heating, carrying out coprecipitation reaction, washing and drying the obtained product, and thus obtaining the precursor.

Wherein the chemical formula of the precursor is Ni_xCo_yMn_zAl_pB_q(OH)₂Wherein x, y, z, p and q are mole numbers, x is more than or equal to 0.6<1，0<y≤0.2，0<z≤0.2，0<p≤0.08，0<q≤0.05，x+y+z＝1。

2. The method for preparing the regenerated precursor material of the waste lithium cobaltate battery according to claim 1, wherein in the step (1), the discharge process comprises the step of soaking the waste lithium ion battery in a 0.2-6% sodium chloride solution for 18-48 hours, wherein the alkali in the adopted alkali solution is one or more of sodium hydroxide, ammonia water and calcium hydroxide, the pH value is 12-14, the soaking time is 1-2 hours, and part of metal impurities (magnesium, calcium, aluminum and the like) are removed.

3. The preparation method of the regenerated precursor material of the waste lithium cobaltate battery is characterized in that the mass ratio of the reducing agent to the black powder is 1: 1-3, and the roasting temperature is 500-800 ℃ in the reducing agent carbon powder used in the step (2); the roasting time is 8-12h, the electrolyte, lithium and Fe in the lithium cobaltate are removed³⁺Reduction to Fe²⁺。

4. The method for preparing the regenerated precursor material of the waste lithium cobaltate battery according to claim 1, wherein the acid used in the step (3) is one or more of sulfuric acid, hydrochloric acid and nitric acid, the acid concentration is 4-6 mol/L, the pH is adjusted to be 4.4-6.4, aluminum and copper impurities are removed, and the pH is adjusted to be 2.7-3.7, and iron impurities are removed.

5. The method for preparing the regenerated precursor material of the waste lithium cobaltate battery according to claim 1, wherein the method for measuring the concentration of cobalt ions adopted in the step (4) is an ICP method, the nickel source is selected from one or more of nickel sulfate and nickel nitrate, the manganese source is selected from one or more of manganese sulfate and manganese nitrate, the boron source is selected from one or more of boron oxide and boron nitrate, and the aluminum source is selected from one or more of aluminum oxide and aluminum nitrate.

6. The method for preparing the regenerated precursor material of the waste lithium cobaltate battery according to claim 1, wherein the precipitant added in the step (5) is one or more of sodium hydroxide, potassium hydroxide and sodium carbonate, and the concentration is 6-7 mol/L; the complexing agent is one or more of ammonia water, ammonium sulfate, oxalic acid and ammonium bicarbonate, the concentration is 4-5 mol/L, the pH value is 10-11, and the solution temperature is 45-60 ℃.

Technical Field

The invention relates to the field of lithium ion battery recovery, in particular to a preparation method of a regenerated precursor material of a waste lithium cobaltate battery.

Background

The decommissioning wave of the first wave power battery is about to come in 2018, and the decommissioned lithium ion battery reaches over 60 gigawatts in 2020. By 2030, the population using electric cars worldwide will reach 2.28 billion. With the rapid growth of electric automobiles, the annual demand of lithium ion batteries is also rapidly growing, which means that more and more lithium ion batteries are going to be retired in the future. Because the waste lithium ion battery contains heavy metals, organic solvents and harmful electrolytes, the waste lithium ion battery has great harm to the environment if not recycled. Meanwhile, the value of impurity metals in the waste lithium ion battery reaches 101 billion yuan by 2020. From this point of view, it is a valuable secondary resource. Recycling of used lithium ion batteries should be considered. The sustainability of lithium ion batteries should be of more interest, and recycling plays an important role.

The waste lithium ion battery contains a large amount of expensive metal cobalt, but the cobalt resource in China is in short supply, the metal recovery rate in the production process is low, the process is complex, and the production cost is high. If the cobalt resource in the waste lithium ion battery can be recycled, the method has great significance in the prior art from the aspects of environmental protection and resource recycling, most of the cobalt in the lithium cobaltate is recycled by single cobalt and then is recycled, and the method is complex and causes high cost. Such as patent [ CN200910117702]Reported by the use of waste LiCoO₂Mixing the powder with alkali metal sodium and potassium salts, roasting at a higher temperature, leaching the roasted product by water, and carrying out cobalt precipitation and lithium precipitation on the leaching solution to obtain cobalt oxalate and lithium carbonate. Patent [ CN200910093727]A method for preparing lithium cobaltate by recycling waste lithium ion batteries is reported, wherein waste LiCoO is obtained by removing electricity from the waste lithium ion batteries, splitting, crushing, treating by NMP and calcining₂Material, then LiCoO₂Mixing the material with natural organic acid and hydrogen peroxide, ball milling to obtain Li⁺、Co²⁺Is added dropwise into the solutionPreparing xerogel by ammonia water and calcining for the second time to obtain the lithium cobaltate electrode material. The lithium cobaltate material prepared by the method has far inferior electrochemical performance, a large amount of impurities exist, and the utilization rate of cobalt ions is low.

Disclosure of Invention

Aiming at the technical problems, the invention provides a preparation method of a regenerated precursor material of a waste lithium cobaltate battery, which has the advantages of simple preparation process, effective utilization of the waste lithium cobaltate material, uniform regenerated precursor particles, good sphericity, narrow particle size distribution and no microcrack; the preparation method is simple and easy to operate, and has little environmental pollution.

The technical scheme adopted by the invention for solving the technical problems is as follows:

a preparation method of a regenerated precursor material of a waste lithium cobaltate battery comprises the following steps:

(1) discharging the waste lithium ion battery by adopting a sodium chloride solution, then disassembling, soaking the positive plate in an alkali liquor, and filtering to obtain black powder;

(2) adding carbon powder into the obtained solution for reduction roasting to remove impurities;

(3) the resulting black powder was dissolved in an acidic solution and the pH was adjusted to obtain a relatively pure cobalt containing solution.

(4) After the concentration of cobalt ions is measured, adding corresponding nickel source, manganese source, boron source and aluminum source into the solution from the outside;

(5) and adding a precipitator and a complexing agent into the prepared mixed solution, adjusting the pH value, heating, carrying out coprecipitation reaction, washing and drying the obtained product, and thus obtaining the precursor.

Wherein the chemical formula of the precursor is Ni_xCo_yMn_zAl_pB_q(OH)₂Wherein x, y, z, p and q are mole numbers, x is more than or equal to 0.6<1，0<y≤0.2，0<z≤0.2，0<p≤0.08，0<q≤0.05，x+y+z＝1。

Preferably, the solution used in the lithium ion discharge process in the step (1) is 0.2-6% sodium chloride solution, the soaking time is 18-48 h, the alkali in the adopted alkali solution is selected from one or more of sodium hydroxide, ammonia water and calcium hydroxide, the concentration is 6-10mol/L, and the soaking time is 1-2 h.

Preferably, the reducing agent used in the step (2) is carbon powder, and the mass ratio of the carbon powder to the obtained black powder is 1: 1-3, wherein the roasting temperature is 500-900 ℃; roasting for 8-12h, removing electrolyte, lithium and Fe in lithium cobaltate³⁺Reduction to Fe^{2 +}。

Preferably, the acid used in the step (3) is sulfuric acid, the concentration of the sulfuric acid is 4-6 mol/L, the pH is adjusted to be 4.4-6.4, impurity metal aluminum and impurity metal copper are removed, the pH is adjusted to be 2.7-3.7, and impurity metal iron is removed.

Preferably, the method for measuring the concentration of cobalt ions used in step (4) is an ICP method, the nickel source is selected from one or more of nickel sulfate and nickel nitrate, the manganese source is selected from one or more of manganese sulfate or manganese nitrate, the boron source is selected from one or more of boron oxide or boron nitrate, and the aluminum source is selected from one or more of aluminum oxide or aluminum nitrate.

Preferably, the precipitator added in the step (5) is one or more of sodium hydroxide, potassium hydroxide and sodium carbonate, and the concentration is 6-7 mol/L; the complexing agent is one or more of ammonia water, ammonium sulfate, oxalic acid and ammonium bicarbonate, the concentration is 4-5 mol/L, the pH value is 10-11, and the solution temperature is 45-60 ℃.

The invention has the beneficial effects that:

(1) the problems of complex recovery process and low recovery product benefit in the recovery of the lithium cobaltate battery material are solved.

(2) The method adopts a simple method to recycle the waste lithium cobaltate anode material, and the regenerated precursor particles are uniform, good in sphericity, narrow in particle size distribution and free of microcracks.

(3) The preparation method is simple and easy to operate, has little environmental pollution and is suitable for large-scale industrial production.

Drawings

FIG. 1 is a flow diagram of a precursor material made in accordance with example 1 of the present invention;

FIG. 2 is an SEM image of a precursor material prepared in example 1 of the present invention.

Detailed Description

The present invention will be further described with reference to the following examples and the accompanying drawings.

Example 1

The embodiment comprises the following steps:

(1) soaking the waste lithium cobaltate battery in a 2% sodium chloride solution for 20h, then drying and disassembling, soaking in a 6mol/L sodium hydroxide solution for 1h, filtering and washing to obtain black powder;

(2) taking 10g of black powder (lithium cobaltate active substance), and roasting the obtained black powder and iron powder in a muffle furnace at 800 ℃ for 8 hours according to the mass ratio of 1: 1;

(3) taking 10g of lithium cobaltate active substance, then dissolving the lithium cobaltate active substance in 100mL of 6mol/L sulfuric acid, adjusting the pH value to be 5, filtering the solution, removing filter residues, removing impurity metal aluminum and impurity metal copper, adjusting the pH value to be 3, filtering the solution, removing impurity metal iron, and finally obtaining filtrate.

(3) Measuring the concentration of cobalt ions in the filtrate to be 1.1mol/L by adopting an ICP method, mixing nickel sulfate with the same concentration with a manganese sulfate solution after measuring the concentration of the cobalt ions, and adding boron oxide and aluminum oxide; adding 5mol/L sodium hydroxide and 5mol/L ammonia water into the prepared mixed solution, adjusting the pH value to 10.5, and adjusting the solution temperature to 45 ℃, wherein the ratio of nickel: cobalt: manganese: boron: aluminum: carrying out coprecipitation reaction on alkaline substances of 8:1:1:0.01:0.01:20, washing and drying the obtained product to obtain a precursor Ni_0.8Co_0.1Mn_0.1Al_0.001B_0.001(OH)₂。

The recycled material prepared in this example was subjected to electron microscope scanning, and as shown in fig. 2 (SEM), the precursor particles were uniform, had good sphericity, particle size of 2-4 μm, and had no microcracks.

Example 2

(1) Soaking the waste lithium cobaltate battery in a 5% sodium chloride solution for 18h, then drying and disassembling, soaking in a calcium hydroxide solution with the concentration of 8mol/L for 1.5h, filtering and washing to obtain black powder;

(2) taking 20g of black powder (lithium cobaltate active substance), mixing the obtained black powder and iron powder according to the ratio of 1: 1.5, placing the mixture in a muffle furnace at 800 ℃ for roasting for 6 hours;

(3) and then dissolving the lithium cobaltate active substance in 200mL of 8mol/L sulfuric acid, adjusting the pH value to 5, filtering the solution, removing filter residues, removing impurity metal aluminum and impurity metal copper, adjusting the pH value to 3, filtering the solution, removing impurity metal iron, and finally obtaining a filtrate.

(3) Measuring the concentration of cobalt ions in the filtrate to be 2.3mol/L by adopting an ICP method, mixing nickel sulfate with the same concentration with a manganese sulfate solution, and adding boron oxide and aluminum oxide; adding 5mol/L sodium hydroxide and 5mol/L ammonia water into the prepared mixed solution, adjusting the pH value to 10.5, and adjusting the solution temperature to 45 ℃, wherein the ratio of nickel: cobalt: manganese: boron: aluminum: carrying out coprecipitation reaction on an alkaline substance of 83:11:06:0.015:0.015:20, washing and drying the obtained product to obtain a precursor Ni_0.83Co_0.11Mn_0.06Al_0.0015B_0.0015(OH)₂The mass of the precursor was 292.45 g.

Example 3

(1) Soaking a waste lithium cobaltate battery in a 4% sodium chloride solution for 16h, then drying and disassembling, soaking in an ammonia water solution with the concentration of 5mol/L for 1.5h, filtering and washing to obtain black powder;

(2) taking 10g of black powder (lithium cobaltate active substance), mixing the obtained black powder and sulfur powder according to the ratio of 1: 1.5, placing the mixture in a tube furnace at 900 ℃ in argon atmosphere for roasting for 8 hours;

(3) and then dissolving the lithium cobaltate active substance in 200mL of 8mol/L sulfuric acid, adjusting the pH value to 4.8, filtering the solution, removing filter residues, removing impurity metal aluminum and impurity metal copper, adjusting the pH value to 3, filtering the solution, removing impurity metal iron, and finally obtaining a filtrate.

(3) Measuring the concentration of cobalt ions in the filtrate to be 1.2mol/L by adopting an ICP method, mixing nickel sulfate with the same concentration with a manganese sulfate solution, and adding boron oxide and aluminum oxide; adding 5mol/L sodium hydroxide and 5mol/L ammonia water into the prepared mixed solution, adjusting the pH value to 10.5, and the solution temperature to 45 ℃, wherein the nickel is: cobalt: manganese: boron: aluminum: carrying out coprecipitation reaction on alkaline substances of 7:2:1:0.02:0.02:20, washing and drying the obtained product to obtain a precursor Ni_0.7Co_0.2Mn_0.1Al_0.002B_0.002(OH)₂The mass of the precursor was 148.72 g.

The above description is only a basic description of the present invention, and any equivalent changes made according to the technical solution of the present invention should fall within the protection scope of the present invention.