One day, electric cars may actually store their energy in carbon-fiber bodies and replace the need for heavy batteries. Research published in October from Chalmers University of Technology in Sweden shows carbon fiber can operate as electrodes in a lithium-ion battery.
A car could feature a structural battery rather than a battery pack. The benefits of weight reduction and miles per electric charge are immense. Research hasn't been carried out in this area before, which makes the discovery promising for future applications.
Researchers tested various types of carbon-fiber materials and found that carbon fibers with small and poorly oriented crystals have very good electrochemical properties—how the material acts as electrodes like in a lithium-ion battery. However, the really rigid carbon fibers with large, highly oriented crystals have poor electrochemical properties. Leif Asp, Professor of Material and Computational Mechanics at Chalmers University of Technology, said less rigidity isn't much of an issue for cars since the carbon fiber with good electrochemical properties is still slightly stiffer than steel. The type with poor electromechanical properties is more than twice as rigid as steel.
Carbon fiber is already a sought-after material in the auto industry, especially for performance cars, for its light weight and high rigidity. Its electrochemical properties only open up vast new possibilities for future electric cars. Asp said a car's body could also hold kinetic energy for sensors and other conductors. He believes all of these functions could cause a car's weight to drop by 50 percent.
The university's research team is now collaborating with the auto and aviation industries to look further into optimizing carbon fiber for vehicles. The discovery could be an even bigger boon for aircraft. Today's planes are far too heavy to run on battery power, but carbon-fiber structural batteries could one day change that.