Are ultracapacitors the key to making hybrids king of the auto market?

Interesting. Maybe Toyota will skip Lithium Ion all together and go straight to capacitors.

 

<div class='quotetop'>QUOTE(zenMachine @ Aug 29 2007, 01:01 AM) [snapback]503636[/snapback]</div>

The Supra uses supercaps because of its requirements and abilities on that particular track: fast power dump, followed by aggressive regen. No battery (with similar storage capacity) can approach the throughput of a supercap, but supercaps don't do so well in the ratio of power to weight or volume to weight. However, some modeling exercises indicate that a supercap array of less than a tenth the storage of a battery could engender superior fuel economy. Cost is also a problem. Race cars don't have that problem.

Hint: Consider a small supercap array in parallel with a Li-ion pack...

 

Watch the video: Like a hybrid car. It's about light rail cars being upgraded with super-caps.
An interviewee actually say, "Like a Prius on steroids."
http://link.brightcove.com/services/link/b...bctid1125950282

And while we are at it . . . how about a solar powered hydrogen fueling station. (This is about a mile from where I live. I wondered what they were building. It can be seen from Highway 50.)
http://link.brightcove.com/services/link/b...bctid1111441743


http://smud.org

 

Research will continue on supercaps. Here is a post that details what I think is a very interesting announcement - if only they would now commercialize the technology.

IMHO, it is only a matter of time before supercaps replace batteries.

 

I don't believe that the capacitors they used on the light rail cars in Sacramento are super caps. They just said that were "large capacitors."

The power to weight and volume to weight ratios should be addressed soon enough. Not sure if they did it with the Supra, but the caps are supposed to start using carbon nanotubes to exponential increase it's capacity without hindering it's ability to nearly instantly recharge.

 

<div class='quotetop'>QUOTE(zenMachine @ Aug 29 2007, 10:01 AM) [snapback]503754[/snapback]</div>

Some call that a "trybrid". But it definitely makes sense, especially if raw materials for advanced batteries (NiMH or Lithium Ion) becomes more expensive, as some have predicted. An ultracap could be thought of as a turbo-booster for your regular hybrid.

I just got pulled into this thread by the phrase "Earth-loving ilk". If that's the kind of ilk I am, I guess that's not too bad.

 

Your Prius already uses Supercaps from Maxwell for it's regenerative braking. The battery can't absorb energy fast enough during braking so they use ultracaps. So in a sense the Prius already has ultracaps in parallel with batteries, although the voltages probably aren't the same.

 

fan-atic, my understanding is that those capacitors only participate in brake system control (hydraulic valves and such) if the Prius 12 volt system fails. All other times, they just sit there.

 

<div class='quotetop'>QUOTE(tochatihu @ Aug 29 2007, 09:23 PM) [snapback]504100[/snapback]</div>

You are probably right. I know that the braking system needs a fallback in case of an accident, and I know that the 200 volt battery is disconnected as soon as the airbag sensor reports a collision. I guess I just assumed the caps did more than that.

 

<div class='quotetop'>QUOTE(Godiva @ Aug 28 2007, 10:15 PM) [snapback]503640[/snapback]</div>

I'm inclined to think that ultra-caps will be the way of the future. But I doubt they'll be available soon enough for Toyota to bypass lithium. Just as the Prius is a baby step toward PHEV, which itself will be a step toward 100% electric transportation, lithium will probably be needed for a while before ultra-caps are ready for market.

I'd love to have my Xebra run on ultra-caps, but even lithium would be wonderful. With lithium batteries in my Xebra I'd never have to drive the Prius except for extended road trips.