Recent progress on key materials and technical approaches for electrochemical lithium extraction processes

The supply and demand of lithium resources are seriously unbalanced due to the rapid growth of energy storage technologies designed to meet proposed carbon emission reduction targets. Lithium resources in the form of liquid solutions, such as seawater, salt-lake brine, and underground brine contribute greatly to this development due to their low cost and relatively abundant reserves. Electrochemical methods are particularly promising to extract lithium from solutions due to their excellent selectivity, environmental friendliness, and low energy consumption. From the perspective of fundamental research on new technologies, it is critical to maximize lithium extraction ability as well as potential applications. In this paper, operation modes of electrochemical lithium extraction processes as well as significant developments of key electrode materials are reviewed. Trends in routes for development are analyzed, and future research directions are correspondingly identified.