World´s first battery that charges on Air

The world’s first battery fuelled by air, which could provide up to 10 times the energy storage of designs currently available and could power electric cars, mobile phones and laptops, has been unveiled. Scientists say the revolutionary ‘STAIR’ (St Andrews Air) battery is charged in a traditional way but as power is used or ‘discharged’, an open mesh section of the battery draws in oxygen from the surrounding air. This oxygen reacts with a porous carbon component inside the battery, which creates more energy and helps to continually ‘charge’ the cell as it is being discharged, the Daily Telegraph reported.
By replacing the traditional chemical constituent, lithium cobalt oxide, with porous carbon and oxygen drawn from the air, the cell is much lighter than current batteries. And as the cycle of air helps re-charge the battery as it is used, it has a greater storage capacity than other similarsized cells and can emit power up to 10 times longer. “The key is to use oxygen in the air as a reagent, rather than carry the necessary chemicals around inside the battery,” Peter Bruce of the University of St Andrews, who’s part of the research team, said. According to Bruce, the battery is much smaller and lighter so better for transporting small applications. The size is also crucial for anyone trying to develop electric cars as they want to keep weight down as much as possible, he said.

Bruce reckoned his kit, in addition to being light, could be cheap, as the porous carbon matrix which holds the Li2O2 ought to be economical. “Our target is to get a five to ten fold increase in storage capacity, which is beyond the horizon of current lithium batteries,” he said. “The key is to use oxygen in the air as a re-agent, rather than carry the necessary chemicals around inside the battery.”
The four-year research project began two years ago and is scheduled to end in 2011. Bruce expected it would be at least five years before the STAIR cell is commercially available.