What is the F/cm^2 for a commercially available supercapacitor? Much of the literature is on newer types of carbon, such as graphene, but are commercially available supercapacitors based on activated carbon? http://www.pnas.org/content/suppl/2015/03/22/1420398112.DCSupplemental In this article published on March 23, 2015, the F/cm^2 is 300mF/cm^2 (.3F/cm^2) for activated carbon (Table S1, p.16), yet references the information from an older article. The reference is to: Simon P, Gogotsi Y (2008) Materials for electrochemical capacitors. Nature Materials 7: 845-854. http://rsta.royalsocietypublishing.org/content/368/1923/3457 The authors of the older article state, "Double-layer capacitance for carbon materials in liquid electrolytes is in the range of 5 to 20 μF cm−2, depending on the electrolyte." in this different but more up to date 2010 article. I have not unraveled a supercapacitor, but the range of 5 to 20 μF cm−2 seems rather low compared to the small size of supercapacitors commercially available, but is the .3F/cm^2 stated in the more recent article accurate?