When we think of critical energy resources, oil, wind, coal, and sunlight are some of the first to come to mind. But one key mineral plays an essential role in keeping the electric grid running, and the U.S. Geological Survey just discovered a vast reserve of it in the eastern United States. According to a new study published in Springer Nature, the Appalachian region contains an estimated 2.3 million metric tons of economically recoverable lithium concentrated in the Carolinas, Maine, and New Hampshire. That’s enough to replace 328 years of U.S. imports based on last year’s level. While not a fuel source itself, lithium is the primary component of utility-scale energy storage systems, which stabilize the power grid , balance supply and demand, and support renewable energy integration. Lithium batteries also power consumer electronics, medical devices, electric vehicles , and other essential technologies.…