Li<sub>2</sub>CO<sub>3</sub> Recovery through a Carbon-Negative Electrodialysis of Lithium-Ion Battery Leachates
Meng Shi, Luis A. Diaz, John R. Klaehn, Aaron D. Wilson, Tedd E. Lister
Abstract
Recycling of lithium-ion batteries (LIB) has focused on the recovery of metals such as Co and Ni due to their intrinsic values. Among these metals, recycling of Li requires hydrometallurgical routes that are not widely implemented due to the higher costs associated with energy and chemical consumptions. This makes Li recovery from recycling less economical than obtention from mineral ores. In the present study, Li as well as Mn were recovered through electrodialysis (ED) from the leachates of spent LIBs by employing a CO2-capture agent N-methyldiethanolamine as a regenerable catholyte. Surrogate solutions and Li-rich leachates were tested for the separation and recovery of Li and Mn as Li2CO3 and MnCO3, respectively. The purity of recovered Li2CO3 99.6% achieved battery-grade purity levels from both surrogate and leachate solutions. It was observed that MnO2 was deposited on the Pt anode only from the surrogate solutions. Energy consumption of the ED was low at 0.5 kW h/g Li. The overall process recovered high-purity Li from LIB leachate, with CO2 being the only chemical consumed. This process is presented as an environment-friendly and energy-effective method in Li2CO3 recovery from LIB materials.