"lew hartswick" wrote in message
...
Doug Miller wrote:
I think the wave of the future is going to be in electric vehicles, using
the emerging "ultra-capacitor" technology. Capacitors have three
advantages over batteries for use in powering vehicles: they charge in
seconds instead of hours, they're able to deliver power more rapidly when
needed (e.g. accelerating from a dead stop, passing, or climbing hills),
and the ultra-capacitor shows promise of attaining a much higher energy
density (power to weight ratio) than is possible with any current battery
technology.

I don't know anything about these "ultra-capacitors" BUT I have had
lots of experience with various electrolytics and if the construction
is suitable for high energy output and a failure, such as a major
penetration were to occur there would be a VERY LARGE release of
energy. :-)
...lew...

The voltage is extremely low, however. It's often less than 2 volts per cap.
That's how they get such enormous capacity; the plate gap is infinitesimal.

--
Ed Huntress