Insights into electrochemical paradigms for lithium extraction: Electrodialysis versus capacitive deionization

Efficient lithium extraction and separation technologies are increasingly imperative owing to the rising demand for lithium in energy storage and electronics. However, the elevated energetic and monetary costs relative to conventional thermal and pressure separation methods, such as reverse osmosis and distillation, significantly diminish the attractiveness of this endeavor. Recently, electrochemical methods are extending into the Li+ separation and extraction technologies, including electrodialysis and capacitive deionization. This work systematically reviews recent advancements in these electrochemical extraction methods for lithium concentration. First, it systematically assesses the key evaluation parameters including extraction capacity, selectivity factor, and specific energy consumption. Moreover, advanced characterization methods crucial for comprehending the intricacies of these electrochemical technologies are outlined. Specifically, this study elucidates the extraction principles of these electrochemical methods, consolidates the current state of advancement in these extraction techniques, and juxtaposes the performance parameters of these methods. Finally, it anticipates current challenges and delineates future research directions for lithium extraction via electrodialysis and capacitive deionization techniques, thereby furnishing guidelines for lithium extraction endeavors.