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Now and Zenn? Potential game changer for electric vehicles

By Richard Kubin on October 17, 2008

I recently attended the 5th Annual Merriman Curhan Ford Investor Summit in San Francisco. While there were a broad spectrum of companies represented (I found the Smith & Wesson presentation interesting), the largest number fell under the ’clean-tech’ or ‘green-tech’ category. These were also quite diverse, ranging from energy storage and smart grid technologies to solar to ’clean’ coal to hybrid and electric vehicles to Brazilian bio-fuels – I could easily write a blog on each!

Of the presentations I saw, the one that had perhaps the broadest potential impact (and a standing room only crowd) was from Ian Clifford, CEO of Toronto, Canada based Zenn Motor Co. Currently, they manufacture and sell the ZENN Low Speed Vehicle (LSV), also referred to as a Neighborhood Electric Vehicle (NEV). This is a ‘traditional’ small electric car that uses six lead-acid batteries for energy storage, has a 30-50 mile range, and is limited under FMVSS 500 regulations to 25 mph. While it’s an interesting design and quite useful for campus, fleet, gated community and even city use, it is not going to replace the family car.

What everyone wanted to hear about was Zenn’s upcoming, highway-capable electric vehicle based on the new EEStor technology. In case you haven’t heard, EEStor is the real game changer in energy storage today. This secretive company (EEStor still doesn’t have a Web site up) based in Cedar Park, Texas, claims to have invented a new ultracapacitor energy storage system that can power an electric car for 300 miles and recharge in only three to five minutes. While there are many skeptics, Ian was very confident that the technology will work. So much so that Zenn acquired a 3.8% share of EEStor for $2.5 million and has the option to buy another 7.6% for $5 million, if certain developmental milestones are achieved. In exchange, Zenn has exclusive rights to sell these ‘batteries’ into the automobile and golf cart (4-wheeled vehicles) industry. Kleiner Perkins Caufield & Byers and Lockheed Martin are also major investors in EEStor.

Although details are still very sketchy, the EEstor batteries are reportedly based on multilayered, barium titanate ceramic capacitor technology. While there are multiple performance measures for energy storage, a key metric for vehicles and portable products is energy density, measured in mega-Joules per kilogram (MJ/kg) – basically, the amount of energy that can be stored per unit volume or mass.

Lithium-ion batteries, the most prevalent for portable devices and even high-end electric vehicles (the Tesla roadster uses 6,831 laptop type Li-ion cells) provide 0.54–0.72 MJ/kg – production EEStor cells are expected to provide 2.5 MJ/kg – three to five times the energy density of Li-ion batteries – which should provide much smaller form factors for equivalent power. They also expect a discharge rate of only 0.02% over 30 days compared with a rate of 1% over 30 days for Li-ion. Another key factor is related to longevity and toxicity, which also factors into lifecycle environmental impact. EEStor claim that their batteries contain no toxic materials, which has been a concern with most other battery technologies. As to lifespan, most traditional battery technologies, Li-ion included, have limited recharge cycles and tend to degrade as cycled. While EEStor has not made any claims yet in this area, capacitors in general do not exhibit this same characteristic, which should mean greatly extended lifetimes.

Latest reports are that EEStor is meeting all of its technical milestones according to independent laboratory validation, and Ian is planning for a fall 2009 release of the highway rated Zenn electric cars. If all goes according to plan, Zenn will then be in a position to license their entire drivetrain technology to other automakers… not bad for a little Canadian start-up (full disclosure: I am a proud fellow Canadian).

Of course, the short charging rate would require specialized equipment to handle the current load, but that could be a viable market transition for gas stations. Zenn expects a two hour charge time from a 220V household outlet.

This could be a real game changer within the next five years with the potential to reduce our dependence on all oil, foreign and domestic, while also driving new jobs. It’s definitely one to keep an eye on. If only McCain or Obama could take credit….

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