Supply
In 2008, R. Keith Evans, a recognized worldwide lithium expert, updated the quantification of lithium reserves. This review was prompted by speculation that worldwide lithium reserves may not be sufficient to support a future exponential increase in HEV/PHEV/EV lithium battery demand.  Evan's 2010 data, shown below, provides ample assurance that lithium reserves are more than sufficient to meet demand.

One of the most promising factors of advancing lithium technology is the element’s prevalence. Global lithium deposits are very large and dispersed with additional deposits numbering in millions of tons, still being discovered. In addition to the millions of tons scientists are already aware of, untapped deposit discoveries in Afghanistan, Tibet and the US have made recent international headlines.

With actual scale production utilizing only 12% of the total reserves discovered to date, the future of lithium technology could not be more promising.
Global Lithium Reserves (Tons LCE)

Source: Lithium Supply & Markets 2010 Conference

Global Lithium Reserve Locations

Source: Lithium Supply & Markets 2010 Conference