Lithium can also be recycled an unlimited number of times

July 10 [Wed], 2013, 11:53
The demand for Li-ion batteries is increasing, and finding sufficient supply of lithium as a raw material is testing the mining industry. A compact EV battery (Nissan Leaf) uses about 4kg (9 lb) of lithium. If every man, woman C650 laptop battery and teenager were to drive an electric car in the future, a lithium shortage could develop and rumor of this happening is already spreading.

About 70 percent of the world’s lithium comes from brine (salt lakes); the remainder is derived from hard rock. Research institutes are developing technology to draw lithium from seawater. China is the largest consumer of lithium. The Chinese believe that future cars will run on Li-ion batteries and an unbridled supply of lithium is important to them.

In 2009, total demand for lithium reached almost 92,000 metric tons, of which batteries consume 26 percent. Figure 1 illustrates typical uses of lithium, which include lubricants, glass, ceramics, pharmaceuticals and refrigeration.

Most of the known supply of lithium is in Bolivia, Argentina, Chile, Australia and China. The supply is ample and concerns of global shortages are speculative, at least for the moment. It takes 750 tons of brine, the base of lithium, and 24 months of preparation to get one ton of lithium in Latin America. Lithium can also be recycled an unlimited number of times, and 20 tons of spent Li-ion batteries yield one ton of lithium. This will help the supply, but recycling can be more expensive than harvesting new supply through mining.

Named after the Greek word “lithos” meaning “stone,” lithium is inexpensive. The raw material costs a fraction of one cent per watt, or less than 0.1 percent of the battery cost. A $10,000 battery for a plug-in hybrid contains less than $100 worth of lithium. Shortages when producing millions of large batteries for vehicles and stationary applications may increase the price. Cobalt, another component found in some Li-ion batteries, is expensive and if required in high volume, demand for this hard and lustrous gray metal could cause global shortages.

At the time of writing, there are no other materials that could replace lithium, nor are battery systems in development that offer the same or better performance as lithium-ion at a comparable price. Rather than worrying about a lack of lithium, graphite, the anode material, could also be in short supply. A large EV C650D laptop battery uses about 25kg (55lb) of anode material. The process to make anode-grade graphite with 99.99 percent purity is expensive and produces much waste.

There is also a concern about pending shortages of rare earth materials for permanent magnets. Electric motors with permanent magnets are among the most energy efficient, and these are finding their way into EV powertrains. China controls about 95 percent of the global market for rare earth metals and expects to use most of these resources for its own production.
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