Bromine Enabled Selective Leaching of Li+ from Battery Cathode Active Material for Li-Ion Battery Recycling

To meet the growing demand for lithium ion batteries (LIBs) and to mitigate environmental impact from spent battery waste, efficient recycling processes are needed. Hydrometallurgy, the process by which valuable elements are separated and extracted from waste, offers promise but suffers from long leaching durations and high greenhouse gas emissions due to the production of chemicals used in these processes. One less explored option in the hydrometallurgy process is through selective leaching. Selective leaching, specifically of the Li-ion, would drastically reduce separation steps in the industrially common hydrometallurgical process.In this work, we demonstrate the selective leaching of lithium from NMC811 and LFP by leveraging Br2 as a leaching solution. Over 85% leaching efficiency for lithium is achieved in the Br2 leaching solution in just 30 minutes, while nickel, manganese, and cobalt achieve leaching efficiencies greater than 95% in under 30 minutes when using Br2 as an oxidizing agent alongside H2SO4. We also investigate the HBr/Br2 system as a leaching solution to enable Br2 circularity, finding similar selective leaching behavior with Li, but at lower efficiencies.