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Old 01-04-2009, 07:47 PM   #40 (permalink)
MPaulHolmes
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Quote:
Originally Posted by The Atomic Ass View Post
I think any capacitor that could hold that kind of charge, (we'll say, 5k watt-minutes?) Would probably be unreasonably expensive. But then again I can't claim to have priced such a thing. I only remember 4 years ago, when I was building up a stereo in my truck, looking at ultra-capacitors for the amplifiers. And there, I was looking at peaks of ~100A for <1 second. Even then prices were sky-high.
Maxwell Ultracapacitors are used quite a bit for hard acceleration over several seconds, to protect battery packs. One guy has a blog about how he did it with a bunch of their ultracapacitors that they were selling on clearance (they were making a new version). He said it made the battery pack feel very stiff, meaning there was almost no voltage drop under acceleration. I don't remember where his blog is, but just do a search for maxwell ultracapacitors ev conversion or some such thing.

It is a very expensive option, though. You need like 50 - 100 of them, and they are around $100 each!
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