Scalable Hollow Carbon Fiber for Lower-cost, Lighter Weight Composites: Concept and Early Results

Carbon fiber is an excellent material for use in applications requiring high tensile properties and low weight. In particular, PAN-based carbon fiber is the most widely employed type for composite applications, including use in composite overwrapped pressure vessels for hydrogen storage. However, these desirable specific properties come at a high cost compared to more traditional materials (metals, for example). In addition, only incremental improvements to carbon fiber specific properties have been achieved over the last several decades. As the demand for lower cost and higher performance carbon fiber continues to increase, a step change in carbon fiber technology is needed. Here we present a scalable hollow carbon fiber for lower cost, lighter weight composites. The hollow carbon fiber concept is introduced, including the rationale behind the concept, and potential cost and performance estimations explained. Finally, the current state of the technology is highlighted. In all, a hollow carbon fiber that conserves the tensile performance of the incumbent T700S carbon fiber would offer faster oxidation, lower carbon fiber cost, lower hydrogen storage system cost (and higher gravimetric capacity), while also being an inherently scalable technology.