Supercapacitors Using Single-Walled Carbon Nanotube Electrodes

The key factors determining the performance of supercapacitorshave been studied using single-walled carbon nanotube (CNT) electrodes. Heat treatment at high temperatures is found to increase the capacitance and reduce the CNT electrode resistance. A very efficient energy storage device was obtained with a CNT-Ni foam hybrid electrode as the energy density does not change appreciably with increasing power density due to its small equivalent series resistance (ESR). This approach demonstrates the possibility of using CNTs as energy storage devices.