Simple Capacitors to Supercapacitors - An Overview

Abstract

The renaissance of electrical/electrochemical double layer capacitors is occurring at a phenomenally high rate as the significant role of these power storage devices in traction, space flight technology, power electronics and other related fields is recognized. The needs of to-day’s computer world cannot be fulfilled by the conventional capacitors such as electrostatic and electrolytic capacitors as their utility is limited to certain specific applications. Electric double layer capacitor (EDLC) uses carbon as the electrodes and stores charge in the electric field at the interface. It uses either aqueous or nonaqueous electrolyte. It gives high power density but low energy density. So the next generation electrochemical double layer capacitor or super capacitor which uses transition metal oxide as the electrode material along with carbon has been under innovation which is expected to deliver both desirable power and energy densities. In this overview, an attempt to provide information on the chronological order of development of capacitors and the related research work is made.