Car bodies could be batteries

Bye bye battery?

Researchers from Imperial College London and industry partners are developing a prototype material which can store electrical energy like a battery but is also lightweight and flexible enough to act as a casing, or even the bodywork of a vehicle.

Ultimately, they expect that this material could be used in hybrid petrol/electric vehicles to make them lighter, more compact and more energy efficient, enabling drivers to travel for longer distances before needing to recharge their cars.

The material, which has been patented by Imperial, could potentially be used for the casings of many electrically powered devices such as mobile phones and computers, so that they would not need a separate battery. This would make such devices smaller, more lightweight and more portable.

“We think the car of the future could be drawing power from its roof, its bonnet or even the door, thanks to our new composite material," said Dr Emile Greenhalgh, from the Department of Aeronautics at Imperial College London and co-ordinator of the €3.4 million project. "Even the Sat Nav could be powered by its own casing. We’re at the first stage of this project and there is a long way to go, but we think our composite material shows real promise.”

The scientists are planning to develop the composite material so that it can be used to replace the metal flooring in the spare wheel well in a car's boot. This could enable car makers to reduce the number of batteries needed to power an electric motor. They believe this could lead to a 15 per cent reduction in the car’s overall weight, significantly improving the range of future hybrid cars.

The researchers say that the composite material that they are developing, which is made of carbon fibres and a polymer resin, will store and discharge large amounts of energy much more quickly than conventional batteries. In addition, the material does not use chemical processes, making it quicker to recharge than conventional batteries. Furthermore, this recharging process causes little degradation in the composite material, because it does not involve a chemical reaction, whereas conventional batteries degrade over time.

The material could be charged by plugging a hybrid car into household power supply. The researchers are also exploring other alternatives for charging it such as recycling energy created when a car brakes.

For the first stage of the project, the scientists are planning to further develop their composite material so that it can store more energy. The team will improve the material’s mechanical properties by growing carbon nanotubes on the surface of the carbon fibres, which should also increase the surface area of the material, which would improve its capacity to store more energy.

They are also planning to investigate the most effective method for manufacturing the composite material at an industrial level.

The three-year European Union-funded project includes researchers from Imperial's departments of chemistry, aeronautics and chemical engineering and chemical technology. European academic and industrial partners include Swerea SICOMP, INASCO Hella, Chalmers, Advanced Composites Group, Nanocyl, Volvo, Bundesanstalt Fur Material forschung undprufung, ETC Battery and Fuel Cells Sweden.