http://news.cnet.com/8301-11128_3-10244133-54.html

May 19, 2009 5:14 PM PDT

Future air-fueled battery could store 10 times more power

by Erik Palm

A new type of air-fueled battery being studied could provide up to 10 times the energy storage of designs currently available, and someday be used to power electric cars, mobile phones, and laptops, say researchers.

"Our results so far are very encouraging and have far exceeded our expectations," said professor Peter Bruce, of the University of St Andrews' chemistry department, in a news release Monday.

Diagram of the STAIR (St. Andrews Air) cell. Oxygen drawn from the air reacts within the porous carbon to release the electrical charge in this lithium air battery.

(Credit: EPSRC)

The new idea the researchers are examining is to replace the lithium cobalt oxide electrode in today's rechargeable lithium batteries with a porous carbon electrode. This allows lithium ions and electrons in the cell to react instead with oxygen in the ambient air, according to a press release from the U.K.'s Engineering and Physical Sciences Research Council, which finances the research conducted at the University of St. Andrews in Scotland. The project has received about 1.6 million British pounds ($2.4 million) from the EPSRC.

According to the researchers, the new design could potentially improve the performance of portable electronic devices and provide a big boost to the renewable-energy industry. The researchers see a scenario in which the batteries will enable a constant electrical output from sources such as wind or solar. Also the STAIR (St. Andrews Air) cell could help power electric cars.

The STAIR cell is expected to be cheaper than rechargeable batteries of today, the researchers said. The new component is made of porous carbon, which is much less expensive than the lithium cobalt oxide it would be replacing.

"The key is to use oxygen in the air as a reagent, rather than carry the necessary chemicals around inside the battery," Bruce said.

The four-year research project began two years ago and is scheduled to end in June 2011. Bruce expects it will be at least five years before the STAIR cell is commercially availabl