Electrochemical system with LiMn2O4 porous electrode for lithium recovery and its kinetics

• LiMn 2 O 4 materials can selectively recover lithium from brine. • Porous electrode significantly reduces the lithium extraction time. • An anolyte with low Mg/Li ratio can be obtained. • The energy consumption of the system is only 8.74 Wh/mol. • Porous electrode has good cycling stability. Lithium extraction from brines with high Mg/Li mass ratio is a key technical issue to ensure sufficient lithium supply. In this work, porous LiMn 2 O 4 electrode was prepared to improve the lithium recovery rate and the electrode process kinetics of the LiMn 2 O 4 /Li 1-x Mn 2 O 4 (LMO) electrochemical system. Using the porous LiMn 2 O 4 electrode, the time required for lithium recovery was significantly reduced, and a solution with a low Mg/Li mass ratio was obtained. In addition, the energy consumption of the LMO electrochemical system was only 8.74 Wh⋅mol −1 , and the electrode intercalation capacity remained essentially unchanged after 80 cycles at 17.20 mg⋅g(LiMn 2 O 4 ) −1 . The application of porous electrodes in LMO electrochemical systems can efficiently and economically recover lithium from brines with high Mg/Li ratios.