Structural Energy Storage System Using Electrospun Carbon Nanofibers with Carbon Nanotubes

In the present study, carbon nanofibers containing multi-walled carbon nanotubes (MWCNTs) were fabricated using electrospinning and used as an electrode for structural supercapacitors. Electrospun polyacrylonitrile (PAN) nanofibers were converted to carbon nanofibers with stabilization and carbonization processes assisted by thermal treatment. The surface area of the electrospun carbon nanofiber electrodes was further increased several thousand times using an activation process. Multifunctional supercapacitors were fabricated using electrospun carbon nanofibers and a vacuum resin infusion technique. The specific capacitance was dramatically improved due to the decreased equivalent series resistance and increased surface area of the nanofiber electrodes. Moreover, the carbon nanofiber electrodes helped increase interlaminar fracture toughness of structural supercapacitors because it acted like ‘Velcro’ between the fabric interfaces. This work is a ‘proof-of-concept’ for a simple and effective method to produce an electrode for structural supercapacitors based on the electrospinning technique.