Several public policies are being implemented around the world to promote Electric Vehicles (EVs) in order to tackle the problems of climate change and fossil fuel depletion. In general, EVs produce fewer emissions that contribute to climate change and smog than fossil fuel based traditional vehicles. Most EVs are powered by Lithium Ion Batteries (LIB) but other options include Nickel-Metal Hydride Batteries, Lead Acid Batteries and Ultra capacitors. It is noteworthy that all of these powering options utilize naturally occurring substances on Earth that exist in a finite quantity. In this article, we analyze amount of lithium used in LIB to explore long term sustainability of EVs. We consider a scenario where all fossil fuel based passenger cars are replaced by EVs. Although the analysis presented here is for lithium, a similar methodology can be adopted for other power sources that require naturally occurring substances.