The U.S. Geological Survey (USGS) has identified an estimated 2.3 million metric tons of undiscovered, economically recoverable lithium oxide in the Appalachian Mountains, with the largest deposits located in the Tin-Spodumene Belt spanning North and South Carolina. The find, valued at approximately $90 billion, marks a major domestic resource for a mineral critical to battery production and classified by the Department of the Interior as essential for national security and economic growth.

The United States currently imports over 25% of its lithium, primarily from Chile and China, making the discovery a strategic shift toward energy independence. The Appalachian region previously served as the world's leading lithium source during the mid-20th century, and federal agencies including the Department of Energy and the National Renewable Energy Laboratory are now assessing the feasibility of restarting extraction to meet the Biden-Harris administration's goal of 50% electric vehicle sales by 2030.

Lithium from hard-rock pegmatites in the Appalachians offers a different environmental profile compared to brine-based extraction methods used overseas, though impacts are still under study. The Federal Consortium for Advanced Batteries is pushing to build a full domestic supply chain, from mining to recycling, in line with Inflation Reduction Act requirements that mandate U.S.-sourced minerals for clean vehicle tax credits.

The Internal Revenue Service and Department of the Treasury have formalized rules tied to the Act, increasing incentives for domestic lithium development. The USGS will conduct further geological surveys in 2025 to refine reserve estimates, and the Department of Energy plans to issue preliminary exploration permits by early 2026.