Lithium Air Batteries – Battery Education

Researchers at Argonne National Laboratory are developing a new battery technology that by some estimates would pack 5 to 10 times the amount of energy today’s lithium ion batteries hold. This incredible improvement would be enough energy to allow electric cars to travel up to 400 miles before recharging. The new battery technology is called lithium air (li-air).

A li-air battery makes electricity by transferring oxygen through a porous carbon electrode where it reacts catalytically with li-ions and electrons to form a solid lithium oxide. The solid lithium oxide fills the pore spaces inside carbon electrodes as the battery discharges. Then when the battery is recharged, the lithium oxide decomposes again, releasing lithium ions and freeing up pore space in the carbon. The remaining oxygen is released back into the atmosphere.

The four main challenges to li-air battery technologies are:

Safety
Cost
Battery Life
Performance

Safety

In terms of safety the great challenge is a materials one. Li-air batteries currently incorporate metallic electrolytes. When you recharge lithium electrodes they become highly reactive with respect to the metallic electrolyte and if these highly charged electrodes are not managed safely the chain reaction could be highly explosive. This is of particular concern when we consider the realities of roadway driving and the potential for car crashes. How would a li-air battery stand up to severe impact?

Cost

With research costs well into the tens of millions and the expectation by a consensus of researchers that a safely designed li-air battery would not be commercially viable for another 20 years the development costs will be extremely high and will the battery life and performance for consumers warrant the investment costs?

Battery Life

The other aspect to this is how long with the battery lasts. How many charge-discharge cycles will a li-air battery have? We know the current li-ion batteries have a charge –discharge cycle between 300-500 will li-air be comparable? Will it offer more? Are we talking 1 year of life or 5 and what variables would affect this range differential?

Performance

What does 5-10 times the amount of energy stored equate to in terms of real application to a potential user? Can we expect to get up 400 miles is li-air electric car before we have to recharge?

These four challenges to Li-air battery technology are enough of an obstacle to make the possibility of this promising technology to take up to 20 years to come to market. The idea is good and perhaps the theories will pan out someday, however that someday will have to wait for future generations.