New mega-farad ultracapacitors

Abstract

This paper reports the successful creation of a new ultracapacitor structure that offers a capacitance density on the order of 100 to 200 Farads per cubic centimeter; versus the current state of the art capacitance density of 1 F/cm3. The principle behind the new ultracapacitor structure is the insertion of a few nanometers-thick layer of barium strontium titanate as an interface between an activated carbon electrode and a suitable electrolyte, such as acetonitrile or propylene carbonate. The new ultracapacitors are highly needed in hybrid vehicle applications, because any significant increase in the energy storage capability of the ultracapacitors leads to substantial improvement in the fuel efficiency of hybrid vehicles. © 2006 IEEE.