[en] Lithium's unusual properties as a metal have propelled it into the forefront of materials destined to play an important role in the economy of the next century. It promises to be an important component of the breeder blanket of controlled thermonuclear reactors as well as hybrid fission-fusion reactors that may serve to transmute high-level waste generated by conventional fission reactors. About 100 to 1000 kg of natural lithium are required per megawatt-electric. Lithium-water-air and lithium-sulfide batteries have been tested and show great promise of becoming the batteries for electric automobiles in the future. One of these batteries can just as well serve for local off-peak energy storage in the utility industry. Similarly, they can be used for intermittent energy sources (wind, tidal, and solar power). The current lithium reserves and resources will be hard put to meet customary demands for lithium, which are increasing at a rate of 8 to 10 percent/yr, so the U.S. supply will have to be expanded by increased exploration