Unlike conventional land-based resources for lithium (Li), which are concentrated in a few geographic locations (e.g., closed-basin brines, pegmatites, lithium clays, and zeolites), seawater provides a massive and evenly distributed global Li reserve (230 billion tons), albeit at low (<1 parts per million) concentrations. As global Li consumption continues to rise over the next few decades, the development of cost-competitive technologies for Li extraction from seawater warrants intense research. In this issue of Joule, Steven Chu and colleagues introduce an electrochemical methodology to selectively remove Li from seawater. This selective removal is accomplished by exploiting the differences in electrochemical potentials for the Li⁺ and sodium (Na)⁺ insertion/extraction reactions, and their diffusion activation barriers in the FePO₄ framework of the ordered olivine MeFePO₄. This work demonstrates the possibility of energy-efficient Li extraction from seawater at relatively high rates with long-term stability by using the electrochemical ion insertion/extraction in battery electrode materials.

不同于传统的锂基陆上资源（Li）集中在几个地理位置（例如，封闭式盆地盐水，伟晶岩，锂粘土和沸石），海水提供了庞大且分布均匀的全球Li储量（2,300亿美元）吨），尽管浓度低（<百万分之一）。随着未来几十年全球锂消费量的持续增长，从海水中提取锂的具有成本竞争力的技术的发展值得深入研究。在本期Joule中，Steven Chu及其同事介绍了一种电化学方法，可以选择性地从海水中去除Li。这种选择性去除是通过利用Li ⁺和钠（Na）^+的电化学势的差异来实现的有序的橄榄石MeFePO ₄的FePO ₄骨架中的插入/萃取反应及其扩散激活障碍。这项工作表明，通过在电池电极材料中使用电化学离子插入/萃取技术，可以以相对较高的速率从海水中高效节能地提取锂，并具有长期稳定性。