Booming electric vehicle sales have spurred a growing demand for lithium. But the light metal, which is essential for making power-packed rechargeable batteries, isn't abundant. Now, researchers report a major step toward tapping a virtually limitless lithium supply: pulling it straight out of seawater. "This represents substantial progress" for the field, says Jang Wook Choi, a chemical engineer at Seoul National University who was not involved with the work. He adds that the approach might also prove useful for reclaiming lithium from used batteries. Lithium is prized for rechargeables because it stores more energy by weight than other battery materials. Manufacturers use more than 160,000 tons of the material every year, a number expected to grow nearly 10-fold over the next decade. But lithium supplies are limited and concentrated in a handful of countries, where the metal is either mined or extracted from briny water.- Science