Electrochemical recovery lithium from brine via taming surface wettability of regeneration spent batteries cathode materials

Lithium-ion batteries are ubiquitous as energy storage technology in mobile electronics and hybrid electric vehicles. There is a necessity to develop new lithium extraction technologies to meet growing demand and diversify the global lithium supply chain. Electrochemical recovery is a promising method of Li+ extraction that is highly lithium selective, environmentally friendly and economical. In this work, the hydrophilicity of ZnO-coated LiMn2O4 (derived from regenerated lithium-ion battery cathode materials, rLMO) is modulated to construct electrochemical systems for the recovery of lithium from brine. The effects of current density, potential, the concentration of simulated brine, and the concentration of recovery solution on lithium extraction from the simulated brine are investigated via the response surface methodology-central composites design. The structure and morphology of the materials during lithium extraction were studied using SEM, TEM, XRD and Raman, and the electrochemical lithium extraction performance was investigated by cyclic voltammetry, galvanostatic and constant voltage. rLMO with Li vacancies has the dual functions of selective lithium extraction and ZnO coating to adjust the interface hydrophilicity, which can effectively improve the electrochemical performance. The average electro-adsorption capacity of the ZnO-modulate rLMO was 13.12 mg/g/cycle over five cycles. In the high-concentration feed solution (240 mM), the maximum adsorption capacity was 41.06 mg/g.