Recovery of Lithium from Waste LIBs Using Sulfuric Acid Roasting and Water Washing

Lithium (Li) is one of the important elements used in the manufacturing of lithium-ion batteries (LIBs). In view of increasing demand of Li, lack of natural resources and generation of huge spent LIBs containing black mass (LiCoO₂), present paper reports a developed process at CSIR-NML consist of sulfuric acid roasting followed by water leaching for selective recovery of Li from black mass (LiCoO₂) of spent LIBs. Different process parameters, viz., time, temperature, mass to volume (m/v) ratio were optimized for the roasting of cathode material. Result shows that roasting at 750 °C in 120 min maintaining m/v ratio of LiCoO₂/H₂SO₄: 1/0.2, the Li₂O of cathode material gets converted into Li₂SO₄. Further, 95.8% Li was dissolved from roasted mass at 75 °C using de-ionized water within 120 min. Thereafter, Li was precipitated as carbonate (Li₂CO₃) using Na₂CO₃ between pH 11 and 12 at 90 °C.