Low cost, high capacity air battery under development

We've heard of the air car, but now there's the air battery.

This new British invention promises a low-weight, high-capacity rechargeable battery that holds big benefits for everything from electronics to electric cars, renewable energy storage, as for wind and solar.

(Image: Diagram of the St. Andrews Air Cell—STAIR—which uses porous carbon that reacts with air from the atmosphere to release an electrical charge. Credit: Engineering and Physical Sciences Research Council.)

The new battery could have 10 times the storage capacity of existing rechargeables, according to a release from the British Engineering and Physical Sciences Research Council, which funded the reseach. See their press release here.

The breakthrough appears to be the use of oxygen from the atmosphere to replace the bulky and heavy components of standard rechargeable batteries.

Says the release: “ Improved capacity is thanks to the addition of a component that uses oxygen drawn from the air during discharge, replacing one chemical constituent used in rechargeable batteries today. Not having to carry the chemicals around in the battery offers more energy for the same size battery. Reducing the size and weight of batteries with the necessary charge capacity has been a long-running battle for developers of electric cars.”

Principal investigator Peter Bruce of the University of St Andrews Chemistry Department said his team has been trying to get a battery with five to 10 times more capacity than current lithium rechargeables—a level of improvement that does not appear possible with the lithium battery technology.

“Our results so far are very encouraging and have far exceeded our expectations. The key is to use oxygen in the air as a re-agent, rather than carry the necessary chemicals around inside the battery,” Bruce said.

The carbon used in the process is also much cheaper than the components of standard rechargeable batteries.

Bruce said it will probably take five more years of work to bring the technology to the market. The research team's initial goal is to produce a prototype that will power a cell phone or MP3 player.

The longer term promise of this battery technology is high capacity, compact size, low cost, reduced toxicity. What's not to like?

© Jan TenBruggencate 2009