Acid-free anodic suspension electrolysis strategy for the efficient recycling of industrial LiCoO2 black mass from spent Li-ion battery

An innovative suspension electrolysis method is proposed for LiCoO 2 recycling. • The electrolysis process can leach aqueous Li ions while generate solid Co oxide. • Direct regeneration of LCO is achieved via a closed-loop solid-state sintering. • Regenerated LCO restored comparable electrochemical properties to commercial LCO. • This strategy is scalable for mass production of industrial LiCoO 2 black mass. An innovative and green anodic “suspension electrolysis” strategy is designed for lithium extraction from industrial spent LiCoO 2 “black powders”, without additional acid, base or oxidizing/reducing agents required. As thoroughly illustrated by the electrolytic mechanism, Li ions driven by the electric energy are leached into the electrolyte while lithium-deficient Li x CoO 2 can be acquired as the anodic residual powders. The electrolysis process achieves an outstanding Li leaching efficiency of 92.1% and the Li ions can be recycled in the form of Li 2 CO 3 through a precipitate reaction by Na 2 CO 3 . The post-produced cobalt oxide and Li 2 CO 3 can be subjected to a solid-phase heat treatment for the regeneration of layered LCO. The regenerated LCO exhibits a discharge specific capacity of 149 mAh/g at 0.5 C, covering around 98.4% of the commercial LCO, and the capacity retention rate reaches up to 91.6% after 200 cycles at 0.5 C. This work provides an eco-friendly and scalable solution for recycling and regenerating spent LCO cathode materials. Download: Download high-res image (151KB) Download: Download full-size image