Removal of Nickel, Cobalt, And Manganese from Leaching Solution of Ternary Positive Electrode Material

Lithium ion batteries have experienced rapid development in daily life and industrial applications since their commercialization in the 1990s due to their significant features such as high output power, high charging and discharging efficiency, and long service life.

With the widespread application of lithium-ion batteries, waste lithium-ion batteries also include positive and negative electrode electrolytes and separators, among which positive electrode materials are mostly LiCoO2, LiMn2O4, LiNiO2, LiNixCoyMn1-x-yO2, LiFePO4. Ternary positive electrode materials have become the most promising materials currently due to their high energy density and excellent cycling performance.

Secondly, from the perspective of resource utilization, the valuable metals contained in ternary cathode materials have high recycling value. China suffers from severe shortages of Li, Ni, Co, and Mn resources every year and relies excessively on imports. In lithium-ion batteries, Co accounts for about 5%~20%, Ni accounts for about 5-10%, Mn accounts for about 7%~10%, and Li accounts for about 2%~5%. If appropriate processes are used to recycle ternary cathode materials, it will have a strong promoting effect on environmental improvement and economic development.

At present, there are two main methods for the disposal of waste lithium-ion batteries in the industry: one is cascade utilization: when some lithium-ion batteries are about to retire, although they cannot meet the current product usage conditions, they can be downgraded and used to continue to utilize their waste heat in other fields; The second is dismantling and recycling: After cracking and dismantling the waste lithium-ion batteries, valuable metal ions in the positive electrode material are extracted using wet or pyrometallurgical processes and further processed.

The preprocessed ternary positive electrode material is leached through appropriate processes to allow the valuable metals in the active material to enter the solution in the form of ions, facilitating the subsequent extraction of valuable metals and the synthesis of ternary positive electrode materials. Extraction process is usually used to complete this step.

The extraction agent separation method is a combination of extraction agent and organic solvent. The extraction agent forms complexes with various ions in the leachate, and the separation is achieved by utilizing the different solubility of the complexes between the two phases.

After extraction, there are still some divalent metals such as nickel, cobalt, and manganese that need to be processed. Firstly, this can be further recovered, and secondly, it can also meet the impact of metals such as nickel, cobalt, and manganese on lithium recovery for some enterprises.