Air-fuelled battery could increase energy capacities ten-fold
A new type of air-fuelled battery could give up to ten times the energy storage of today's batteries, British researchers have claimed.
The improved capacity is thanks to replacing the chemicals used in rechargeable batteries today with a single component that uses atmospheric oxygen during discharge. Not having to include multiple chemicals means more energy for the same size of battery.
Currently being developed by researchers at the University of St Andrews, along with partners at Strathclyde and Newcastle, the Stair (St Andrews Air) cell should be cheaper than today's rechargeables too. The new component is made of porous carbon, which is far less expensive than the lithium cobalt oxide it replaces.
The four-year Stair cell research project, which is funded by the Engineering and Physical Sciences Research Council (EPSRC), reaches its halfway mark in July. It builds on the discovery at St Andrews that the carbon component's interaction with air can be repeated, creating a cycle of charge and discharge. Subsequent work has more than tripled the cell's capacity to store charge.
"Our target is to get a five to ten fold increase in storage capacity, which is beyond the horizon of current lithium batteries," said the project's principal investigator, Professor Peter Bruce of the chemistry department at St Andrews. "Our results so far are very encouraging and have far exceeded our expectations."
The project is focused on understanding more about the battery's chemistry and investigating how to improve it. The research team is also working towards making a Stair cell prototype for small applications, such as mobile phones or MP3 players.
In the longer-term, the new battery could also assist electric vehicle development - reducing battery size and weight has been a long-running battle for developers of electric cars - and give a boost to the renewable energy industry, where batteries can enable a constant electrical output from variable sources such as wind and solar.
"The key is to use oxygen in the air as a reagent, rather than carry the necessary chemicals around inside the battery," said Professor Bruce.
However, he estimated that it will be at least five years before the Stair cell is commercially available.