MadUndergrad writes: "ArsTechnica reports that the small Texas company EEstor has made a breakthrough in supercapacitor technology. Though there is little information available as of yet, according to a recently filed a patent application, EEstor has made use of a barium titanate dielectric to achieve energy densities of around 1600Wh/L. For comparison, this is over ten times the energy density of lead-acid batteries and over four times the energy density of Lithium-polymer batteries. Readers should note that these numbers are those claimed by EEstor, and have not yet been confirmed. However, the ZENN Motor Company plans to begin use of the capacitors before the end of the year."