The Aerocapacitor: An Electrochemical Double‐Layer Energy‐Storage Device

Abstract

We have applied unique types of carbon foams developed at Lawrence Livermore National Laboratory to make an "Aerocapacitor." The aerocapacitor is a high power‐density, high energy‐density, electrochemical double‐layer capacitor which uses carbon aerogels as electrodes. These electrodes possess very high surface area per unit volume and are electrically continuous in both the carbon and electrolyte phase on a 10 nm scale. Aerogel surface areas range from 100 to 700 m 2 /cm 3 (as measured by BET analysis), with bulk densities of 0.3–1.0 g/cm 3 . This morphology permits stored energy to be released rapidly, resulting in high power densities (7.5 kW/kg). Materials parameterization has been performed, and device capacitances of several tens of Farads per gram and per cm 3 of aerogel have been achieved.