Lithium is a soft, silver-white metal that belongs to the alkali metal group
of chemical elements. It is represented by the symbol Li, and it has the atomic
number 3. Under standard conditions it is the lightest metal and the least dense
solid element.
The lithium ion Li+ administered as any of several lithium salts has proved to
be useful as a mood-stabilizing drug due to neurological effects of the ion in
the human body. Lithium and its compounds have several industrial applications,
including heat-resistant glass and ceramics, high strength-to-weight alloys used
in aircraft, lithium batteries and lithium-ion batteries. These uses consume
more than half of lithium production.
Since the end of World War II lithium production has greatly increased. The
metal is separated from other elements in igneous minerals such as those above.
Lithium salts are extracted from the water of mineral springs, brine pools and
brine deposits. The metal is produced electrolytically from a mixture of fused
lithium chloride and potassium chloride. In 1998 it was about 95 US$ / kg (or 43
US$/pound).
Lithium is produced from either hard rock pegmatite (spodumene crystals) or from
salar brines (salt lakes). The two processes are drastically different with one
being the traditional mining and ore processing with rare metals credits, while
the other is more solution evaporation ponds. In recent years there's also been
discoveries of lithium in clay hectorite, however the commercial viability of
this type of deposit is yet to be proven.
Deposits of lithium are found in South America throughout the Andes mountain
chain. Chile is the leading lithium producer, followed by Argentina. Both
countries recover the lithium from brine pools. In the United States lithium is
recovered from brine pools in Nevada. However, half the world's known
reserves are located in Bolivia, a nation sitting along the central eastern
slope of the Andes. In 2009 Bolivia is negotiating with Japanese, French, and
Korean firms to begin extraction. According to the US Geological Survey,
Bolivia's Uyuni Desert has 5.4 million tonnes of lithium. China may emerge as a
significant producer of brine-source lithium carbonate around 2010. There is
potential production of up to 55,000 tonnes per year if projects in Qinghai
province and Tibet proceed.
Worldwide reserves of lithium are estimated to be 23 million tonnes. Using the
battery efficiency figure of 400 g of lithium per kWh, this gives a total
maximum lithium battery capacity of 52 billion kWh which, assuming it is used
exclusively for car batteries, is enough for approximately 2 billion cars with a
24 kWh battery (like a Nissan Leaf).
