EEStor Ultracapacitor and Ultrabattery
There have been so many breakthrough battery claims, but here’s one that might deserve a careful look. The specs are impressive, and the entire manufacturing process has been thought through using processes and equipment already proven in a large-scale commercial operations. The founders bring a wealth of experience as senior technology managers in large companies and startups. The company has maintained a very low profile for several years, and I first talked to them in early 2003.
The claim is for systems at 1/2 the cost of lead-acid (per kwh), and 1/10 the weight. Specifically, they quote a product which at 400 pounds will deliver 52 kwh. Discharge (and charge) rates are at "electronic" speed, and would be limited only by the sizing of the drive circuits and external systems. Thus power ratings can be as high as needed. Selling price would be $3200 at modest production rates, and eventually down to $2100 in high volume.
Here are some specs the company is claiming:
Energy density, Wh/L 606 1513
Specific energy, Wh/kg 273 682
Price, $/kWh 61 40
The company intends to pursue a licensing model, after building their own assembly line to prove out the technology and seed the market.
The technology is basically a parallel plate capacitor with barium titanate as the dielectric. With it’s extremely high permittivity, barium titanate has a long history in capacitors, but one known for high leakage, voltage breakdown and temperature sensitivity. EEStor has confronted these drawbacks head on, and has measurements on prototypes to support their claims.
The product is a ceramic-based unit fabricated with integrated-circuit techniques. The design is based on proprietary technology and there is a patent pending for the production process. There are no corrosive, hazardous, or explosive materials used in manufacturing this product, making this a totally green technology. Also, since it is ceramic, it can be fully charged and discharged using ultrahigh currents and at electronic speeds repeatedly with no degradation to the original specifications. Samples have been rapid-cycled over 1 million times, with no change of any kind. Operating temperature is -40 to +85 deg C.
Until now, electrostatic capacitors have not been considered for energy storage applications because of their low energy density characteristics. Capacitors applied to storage are based upon electrochemical and electrolytic capacitor technologies, which possess higher energy densities. EEStor’s development proposition changes that premise by eliminating the inherent weaknesses of electrostatic technology for storage applications.
A number of major companies have said they would issue a purchase order quickly if specs are met.
The company is currently seeking equity investment of $3.5 million. A business plan is available.
Contact Richard D. Weir, President and CEO
EEStor, Inc. Cedar Park, TX