Future hybrid cars won’t just have powerful batteries - they will be storing energy in their doors, hoods and roofs. Car parts could serve as capacitors, which would allow for smaller and more lightweight batteries, thus increasing a hybrid’s range. Researchers at Imperial College London are working on lightweight auto body components that also store electricity, reports the New York Times. The car frames would be made of plastic composites reinforced with carbon fiber. The resin that binds the carbon fibers is doped with lithium ions - allowing the car’s frame to store electricity. One of the biggest obstacles to increasing a hybrid car’s range is the size and weight of the battery. More powerful batteries can power a car for a longer distance, but they also weigh more, and this saps more energy, counteracting the power increase. This research, which also involves automaker Volvo, takes energy storage out of the battery and directly into the car. The capacitor car parts do not add much energy, at least not right now, but they can be used to smooth the demands on a battery. They could provide an extra jolt to re-start a car after it’s idling at a red light, for instance. Researchers want to test a prototype electric vehicle with an energy-storing trunk floor, whose extra energy storage could reduce the battery's weight by 15%. Ultimately, if capacitor car technology reaches the efficiency of current lithium-ion batteries, only a carbon-fiber roof, hood and doors, will be needed, and they could store enough electricity to power the car for 80 miles. Imperial College has been working on the idea as part of a €3.4 mln, 3 year European Union-funded project which includes researchers from a number of European partners, including automotive firm Volvo. The prototype material is a composite of carbon fibers and a polymer resin which can store and discharge large amounts of energy much faster than conventional batteries. Unlike these there is little degradation in the material over time because there is no chemical process involved, and this also aids more rapid recharging. It is lightweight and strong enough to make car body parts, and could be plugged into the household power supply for recharging. Researchers say the next stage is to further develop the composite in order to store more energy. This may be achieved by growing carbon nanotubes on the surface of the carbon fibers which will increase the surface area, thus improving its storage capacity. They also hope to find alternative options for recharge such as recycling energy created during braking while the car is on the move. Their first test in-situ will be to exchange the metal floor in the car boot, or wheel well, for the composite, and Volvo is investigating the possibility of rolling this out in prototype cars for testing purposes. The addition of the composite combined with a reduced need for heavy batteries could see the car's overall weight drop by up to 15%, consequently increasing the range of future hybrids. The most effective method for manufacturing the composite material at an industrial level is also being investigated. Project co-coordinator, Dr Emile Greenhalgh, from the Department of Aeronautics at Imperial College London, says: “We are really excited about the potential of this new technology. 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. Even the Sat Nav could be powered by its own casing. The future applications for this material don’t stop there - you might have a mobile phone that is as thin as a credit card because it no longer needs a bulky battery, or a laptop that can draw energy from its casing so it can run for a longer time without recharging. 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.”