1165913 - Recycling of Lithium and Cobalt from Spent Lithium-ion Batteries

Lithium-ion battery (LIB) has been widely used in electronic products and electric vehicles largely due to its advantages of high-power efficiency, long life cycle, low cost, and low memory effect. The end-of-life LIBs have rapidly increased in recent ten years, increasing the need for recycling major spent LIB components such as lithium and cobalt with economically efficient and environmentally friendly means. Herein, a feasibility study for recycling lithium and cobalt from spent LIBs was performed. After a mechanical separation for cathode sheets, green chemicals such as citric acid (1 M) and H2O2 (5-10%) were used for a two-step extraction of metal ions from the ground cathode at 343-363 K for 20-30 min. Lithium and cobalt were then selectively captured by an ion sieve (H2TiO3) and capacitive deionization (CDI) (using high surface area and porous activated carbon electrodes for electrosorption of ions) processes, respectively. Correspondingly, Li2CO3 and CoSO4, both LIB raw materials, were recycled by precipitation of the separated Li+ and Co2+ with CO2 and diluted H2SO4. Process water was treated by CDI for citric acid and water recycling/reuse. With the advantages of relatively low energy consumption and high recycling efficiency (>80%), this cost-effective and environmentally friendly recycling process is engineering feasible.