Guide to the Elements - Lithium

(12/6/2008) - Lithium has gotten a lot of attention recently because of its use in batteries.  Rechargeable lithium-ion batteries are used in cell phones, computers, cameras, and perhaps most consequentially, next-generation plug-in hybrids and electric cars.  While there are other types of batteries that might work, Lithium-ion batteries have a higher energy density, which means you can go further on a single charge than with other batteries of comparable weight.  All of the major plug-in hybrids and electrical vehicles in development use lithium batteries.  But is there enough lithium to turn every car electric?

What is Lithium? – With three protons, lithium is the lightest of all metals.  Like other alkali metals, lithium has a single valence electron.  As a result of this property, it is a very reactive substance and is virtually always found in a compound.  This also makes it corrosive.

In addition to its use in batteries, lithium can be used to make ceramics, glass, lubricants, rubber products, dyes, and red fireworks. 

Where does Lithium Come From? – Lithium is found in rocks and the ocean in small quantities (~3ppm).  Commercially useable lithium is found in the brine under salt flats.  Seventy percent of the world’s lithium supply comes from the Andes mountains, where the borders of Boliva, Chile, and Argentina meet.  According to Meridian International Research, Chile’s Salar de Atacama contains the most economically exploitable reserve of lithium due to its concentration and purity, while Bolivia’s Salar de Uyuna contains the largest amount by volume.

How Finite Is the Supply? - A recent paper by Meridian says that the supply of lithium will only be sufficient for a small number of electronic vehicles, and that growing demand for lithium for portable electronic devices will be substantial as well.  Meridian says that, assuming demand from the PED sector increases at its current rate of 25% a year (which is quite substantial, but possible), that after thi is taken into account, enough high-grade lithium will be left for about 1.3 million plug-in hybrids every year by 2015.  While this is still a large number of vehicles, it would only make up a very small fraction of global car sales – 55 million cars were added to the roads in 2007. 

Though its not completely accurate to say that the PED industry would get first dibs on the supply of lithium, this is effectively how it will turn out.  To take one example, the Chevy Volt’s battery is estimated at 16 kWh.  If it takes 2kg of lithium for every kWh of power (another source put it at over 5kg/kWh, but lets look at the most favorable situation), then each battery will contain 32kg of lithium.  Suppose lithium costs $100 per kilogram.  A doubling of the price of lithium will increase the cost of the battery by $3200.  By comparison, if a cell phone battery uses 50g of lithium, a doubling of the price will only increase the price of each battery by $5.  Since this increase in cost will be much easier to absorb by the PED sector, it will be able to consistently outbid car battery makers for lithium.

In total, Meridian estimates that recoverable world lithium totals about 4 million metric tons, enough to make 125 million Volts.  In 2007, there were about 800 million cars in the world, with about 135 million passenger cars in the United States alone.  And that’s pretending that lithium is only used for cars. 

Can Lithium Be Recycled? – Yes, at least that used in batteries.  Lithium in batteries can be reprocessed into lithium carbonate for resale.  Lithium is mined in this form, so it should be easy to reprocess.  That doesn’t mean that lithium batteries are being recycled.    Other lithium, such as that used in medicine, is not easily recyclable. 

Does Lithium present any environmental concerns? – The salt flats in which we find lithium are fragile ecological environments.  Mining these flats causes irreversible change.  If lithium is not processed correctly, it can be hazardous.