EEStor is a company based in Cedar Park, Texas, United States that has developed a superior type of capacitor for electricity storage, which EEStor calls ‘Electrical Energy Storage Units’ (EESU). The EEStor EESU is an integral part of the much anticipated ZENNergy drive-train. Its CEO and president is Richard Weir, who is also a co-inventor named on their principal technology patent.

According to its patent, these units will use high-purity barium titanate coated with aluminum oxide and glass to achieve a level of capacitance claimed to be much higher than what is currently available in the market. The claimed energy density of the prototype is 1 MJ/kg; existing commercial supercapacitors typically have an energy density around 0.02 MJ/kg, while lithium ion batteries are around 0.54–0.72 MJ/kg.


Date Type Amount Investors Valuation
01/01/05 Series A 3M Kleiner Perkins, Kleiner Perkins Unknown
01/01/07 Series B 2.5M ZENN Unknown



CAP-XX: CAP-XX develops high power, high energy supercapacitors in thin, flat, prismatic packages. They enable smaller, lighter,… See Company Profile »
M2E Power: M2E Power, Inc. is an early-stage company developing several breakthrough innovations for renewable power generation. M2E’s… See Company Profile »

View more details about this company's competitors