Tailoring Carbon Nanostructure for High Frequency Supercapacitor Operation.

The possibility of enhancing the frequency performance of electrochemical capacitors by tailoring the nanostructure of the carbon electrode to increase electrolyte permeability is demonstrated. Highly porous, vertically oriented carbon electrodes which are in direct electrical contact with themetallic current collector are produced viaMPECVD growth onmetal foils.Theresulting structure has a capacitance and frequency performance between that of an electrolytic capacitor and an electrochemical capacitor. Fully packaged devices are produced on Ni and Cu current collectors and performance compared to state-of-the-art electrochemical capacitors and electrolytic capacitors.The extension of capacitive behavior to the AC regime (~100Hz) opens up an avenue for a number of new applications where physical volume of the capacitor may be significantly reduced. [ABSTRACT FROM AUTHOR]