World's First Battery Fueled By Air

World's first battery fuelled by air
The world's first battery fueled by air - with 10 times the storage capacity of conventional cells - has been unveiled.

Telegraph
Last Updated: 8:19AM BST 20 May 2009



Scientists say the revolutionary 'STAIR' (St Andrews Air) battery could now pave the way for a new generation of electric cars, laptops and mobile phones. The cells are charged in a traditional way but as power is used or 'discharged' an open mesh section of 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. 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 similar-sized cells and can emit power up to 10 times longer. Professor Peter Bruce of the Chemistry Department at the University of St Andrews, said: "The benefits are it's 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. "Storage is also important in the development of green power. You need to store electricity because wind and solar power is intermittent."

Related: http://www.greendiary.com/entry/the-stair-air-fueled-battery-stores-10-times-more-energy/">The STAIR Air-Fueled Battery stores 10 times more energy

http://www.telegraph.co.uk/scienceandtechnology/science/sciencenews/5353809/Worlds-first-battery-fuelled-by-air.html">LINK

Rechargeable lithium batteries are currently comprised of a graphite negative electrode, an organic electrolyte and lithium cobalt oxide as the positive electrode. Lithium is removed from the layered intercalation compound (lithium cobalt oxide) on charging and re-inserted on discharge.

Energy storage is limited by the lithium cobalt oxide electrode (0.5 Li/Co, 130 mAhg-1). The University of St Andrews design replaces the lithium cobalt oxide electrode with a porous carbon electrode and allows Li+ and e- in the cell to react with oxygen from the air.

Initial results from the project found a capacity to weight ratio of 1,000 milli-amp / hours per gram of carbon (mA/hours/g), while recent work has obtained results of up to 4,000 mA/hours/g. Although the two designs work very differently, this equates to an eight-fold increase compared to a standard cobalt oxide battery found in a mobile phone.

http://insciences.org/article.php?article_id=5065