Separation of nickel from cobalt and manganese in lithium ion batteries using deep eutectic solvents

A cornerstone of the decarbonisation agenda is the use of lithium ion batteries, particularly for electric vehicles. It is essential that effective recycling protocols are developed and this includes the ability to selectively digest and recover components of the cathode materials, most commonly including manganese, cobalt and nickel. This study shows a method by which nickel oxide can be efficiently separated from cobalt and manganese oxides using an oxalic acid-based deep eutectic solvent. The subsequent addition of water to the pregnant solution enables the co-precipitation of cobalt and manganese oxalates. This permits a route to the reformulation of the active materials from high cobalt and manganese content to high nickel content.

Automated summary

This study presents a method using an oxalic acid-based deep eutectic solvent to efficiently separate nickel oxide from cobalt and manganese oxides. The addition of water to the solution allows the co-precipitation of cobalt and manganese oxalates, providing a pathway for reformulating active materials with high nickel content from those with high cobalt and manganese content.