Bipolar membrane electrodialysis with isolation chamber enables high-purity LiOH production with ordinary membranes

Currently, bipolar membrane electrodialysis (BMED) is recognized as an eco-friendly technique to recycle lithium from waste lithium-ion batteries. However, the application of ordinary bipolar membranes has the disadvantage of unsatisfactory product purity due to undesired ion leakage. Herein, we proposed isolation chamber bipolar membrane electrodialysis (ICBMED) to inhibit coion migration, thereby increasing the purity of the regenerated acid and alkali. The experimental results indicate that 97.7%–99.3% of the LiOH generated by the ICBMED using domestic membranes was generated, which is much greater than the 85.7%–94.4% obtained without an isolation chamber. The total cost of the ICBMED for LiOH production with inexpensive domestic membranes was 1.65$/kg-LiOH (US) at 400 A/m², which is lower than the cost of 1.91$/kg-LiOH (US) for flagship membranes with identical product quality. BMED with an isolation chamber provides a viable solution for acid–base production by balancing product quality and cost.