The latest about EEStor, the promising developer of ultracapacitors can be found in a post by Tyler in Clean Break, EEStor Powered cityZenn targeted for fall 2009 the key item is taken from Zenn Motor Company's press release following its annual general meeting of March 28:
The cityZENN is planned to be a fully certified, highway capable vehicle with a top speed of 125 KPH/ 80 MPH and a range or 400 kilometres/250 miles. Powered by EEStor, the cityZENN will be rechargeable in less than 5 minutes, feature operating costs 1/10th of a typical internal combustion engine vehicle and be 100% emission-free! The Zero-Emission, No-Noise cityZENN will be designed to meet the transportation requirements of a large percentage of drivers worldwide.
"EEStor's game-changing energy storage technology is in the advanced stages of commercialization", stated Ian Clifford, Chief Executive Officer. "EEStor has publicly committed to commercialization in 2008 and their first production line will be used to supply ZENN Motor Company."
EEStor is believed to have had trouble developing its product, an ultracapacitor claimed to have a specific energy of 280 watt-hours per kilogram, compared to a lithium ion battery with about 120 watt-hours and a lead-acid gel battery, with only 32 watt hours. (Although ElectroVaya claims 330Wh/kg, so they may not be alone)
The problem is believed, by some, to be in producing the ultra-pure barium-titanate used in the capacitor, which is the key to having the high specific energy. A January 2007 announcement indicated that 1) An automated production line had been proven to meet the requirements for precise chemical delivery, purity control, parameter control and stability and 2) they had completed the initial milestone of certifying purification, concentration, and stability of all of its key production chemicals notably the attainment of 99.9994% purity of its barium nitrate powder. At that time they claimed that they would be shipping product to Zenn in 2007, a year earlier than indicated in the current announcement.
EEStor's recently announced collaboration with Lockheed Martin, which gives the company credibility and is a further indication that the company is making progress. The current announcement seems to be in agreement with the timing indicated in the Lockheed Martin announcement, although, based on past performance, a wait and see position must be held.