Can carbon fiber car panels double as energy storage materials?

Carbon fiber as we know it is one of the most impressive materials in our toolkit. Its incredible lightness and strength has seen it take hold in everything from competitive cycling, to supercar design to cutting edge aircraft. But could it also play a role in energy storage? One team of scientists has been exploring the possibilities, and say that carefully engineered forms of the material do indeed boast the necessary electrochemical properties, raising some interesting possibilities for weight-saving vehicle design.

The research was carried out at Sweden's Chalmers University of Technology and started with a pretty simple premise. Carbon fiber has already been shown to have potential as an electrode material in experimental batteries, while its mechanical properties are well established, so can these two attributes be combined in the one multipurpose material?

Carbon fiber manufactured for structural purposes is generally engineered to be as stiff as possible, but these materials leave a lot to be desired in terms of electrochemical capacity. Conversely, carbon fiber with good electrochemical abilities tends to offer a much lower stiffness.

In what they say was an unexplored field of research, the scientists set out to find a carbon fiber that can fit both bills. This meant studying the microstructures in different types of commercially available carbon fibers, looking at how the crystals within were sized and arranged. They discovered that carbon fibers with greater stiffness had large, highly oriented crystals, while less stiff carbon fiber had small and poorly oriented crystals.