As an energy efficiency advocate, I get excited when materials multitask. So when a recent study revealed that carbon fibers can function as battery electrodes while bearing a structural load, it piqued my curiosity. What if the hood of a car could double as a battery? What if an aircraft’s fuselage effectively stored energy? The possibilities are endless.
Carbon fiber composites are known to provide unparalleled lightweight structural solutions. However, they’ve also been recognized recently for their high electrochemical capacity and potential as negative electrodes for lithium-ion batteries. This combination of structural strength and electrochemical capacity has inspired researchers to explore carbon fiber’s potential to provide “mass-less” energy storage.
A team of researchers from Chalmers University of Technology in Sweden recently investigated the microstructure of carbon fibers. Their study determined that these fibers are able to function as electrodes in a lithium-ion battery and that the fiber’s structure affects its electrochemical properties.
Carbon fibers with small and less organized crystals showed good electrochemical properties but reduced structural stiffness, whereas carbon fibers with large, well-organized crystals offered better stiffness but less effective electrochemical properties. The ideal microstructure for carbon fiber energy storage, therefore, lies somewhere in between.
“We now know how multifunctional carbon fibres should be manufactured to attain a high energy storage capacity, while also ensuring sufficient stiffness,” Leif Asp, Professor of Material and Computational Mechanics at Chalmers University of Technology, stated in a press release. “A slight reduction in stiffness is not a problem for many applications such as cars. The market is currently dominated by expensive carbon fibre composites whose stiffness is tailored to aircraft use. There is therefore some potential here for carbon fibre manufacturers to extend their utilisation.”
The ability to store electrical energy intrinsically in a structural component could impact the electrification of transportation. Do you think that multifunctional materials such as this may influence the design of electric vehicles of the future?