Lithium Resources for the 21st Century

Lithium is an important industrial compound and the principal component of high energy-density batteries. Because it is the lightest solid element, these batteries are widely used in consumer electronics and are expected to be the basis for battery electric vehicles (BEVs), hybrid electric vehicles (HEVs) and plug-in hybrid electric vehicles (PHEVs) for the 21st century. In view of the large incremental demand for lithium that will result from expanded use of various types of EVs, long-term estimates of lithium demand and supply are advisable. For GDP growth rates of 2 to 3% and battery recycling rates of 90 to 100%, total demand for lithium for all markets is expected to be a maximum of 19.6 million tonnes through 2100. This includes 3.2 million tonnes for industrial compounds, 3.6 million tonnes for consumer electronics, and 12.8 million tonnes for EVs. Lithium-bearing mineral deposits that might supply this demand contain an estimated resource of approximately 39 million tonnes, although many of these deposits have not been adequately evaluated. These lithium-bearing mineral deposits are of two main types, non-marine playa-brine deposits and igneous deposits. Playa-brine deposits have the greatest immediate resource potential (estimated at 66% of global resources) and include the Salar de Atacama (Chile), the source of almost half of current world lithium production, as well as Zabuye (China/Tibet) and Hombre Muerto (Argentina). Additional important playa-brine lithium resources include Rincon (Argentina), Qaidam (China), Silver Peak (USA) and Uyuni (Bolivia), which together account for about 35% of the estimated global lithium resource. Information on the size and continuity of brine-bearing aquifers in many of these deposits is limited, and differences in chemical composition of brines from deposit to deposit require different extraction processes and yield different product mixes of lithium, boron, potassium and other elements. Numerous other brines in playas (Great Salt Lake, Searles Lake), geothermal systems (Salton Sea) and oil fields contain lithium, but in low concentrations that add relatively little to estimated global resources. Igneous deposits, which constitute 26% of estimated global resources, consist largely of pegmatites, including past and present producers at Kings Mountain-Bessemer City (USA), Greenbushes (Australia) and Bikita (Zimbabwe), as well as numerous active prospects, especially in Canada and China. Amenability of these deposits to economic extraction is controlled by mineralogy and zoning of lithium, which vary considerably from deposit to deposit. An additional 8% of global lithium resources is estimated to be present in unusual deposits including largely hectorite clays in volcaniclastic rocks at Kings Valley (USA) and jadarite in lacustrine evaporite deposits (Serbia), which present new challenges to both mining and processing. If this highly varied population of deposits can be converted to reserves, lithium supplies for the 21st century EV market are relatively secure.