3000 Farad ultracapacitors, cheap used surplus

Nov 04, 2010 50 Replies

Weeeeeird. I never noticed that!

The coin border appears to take all the induction heat and gets disproportionally crushed. As if the coin was a copper ring. Perhaps the central concavity is simply reflecting the blast of light from whatever illuminator setup they used.

It would have been interesting to use that camera to watch for odd effects on a straight wire rather than a coil.

(((((((((((((((((( ( ( ( ( (O) ) ) ) ) ))))))))))))))))))) William J. Beaty

formatting link
beaty, chem washington edu Research Engineer billb, amasci com UW Chem Dept, Bagley Hall RM74

206-543-6195 Box 351700, Seattle, WA 98195-1700

Still is!

formatting link

Although the caps are at least one or more orders of magnitude lower in capacitance, but you would not want on tossed to you fully charged...

I doubt that seriously, since your "survey" was designed to show that most people call a "cell" a "battery" and had nothing to do with the performance capabilities of any kinds of AA cells.

It would have to be solid silver pipe with perhaps a cooling tunnel blazed through it for some magical cooling liquid.

Otherwise, the 15kA plus pulse pretty much destroys it within a few milliseconds.

Way worse than the rate that a top fuel mix chews up piston tops. Those engines only do about eleven runs.

That is the old way. Nowadays, they break engines down between every run. Far out stuff.

Look at the shots of the coins with holes in them, and the dual metal ringed type coins.

A rat trap-powered contactor? ;-)

Cheers! Rich

s
04watt-

The supercap is much lighter and cleaner than the 12v battery.

No! Fun is fun; let us not be deterred!

Maybe a spark gap. That's easy, anyhow. Or even cruder, just a couple of copper straps for a switch, clapped together. Might be able to make a battery tab welder that way.

That's the surplus price--they cost a *lot* more new. Only cost insensitive apps can afford them right now, like green energy, magic cars, etc.

-- Cheers, James Arthur

Your question was: "How many cells in the batteries?"

My (correct) answer included "One cell per battery" which I humorously derived from a 'popular culture' perspective rather than by actually doing the arithmetic to determine how many hundreds of cells per battery would be required in order to match the short circuit current of the ultra-capacitor.

My answer correctly showed:

1) That I clearly understood *why* you asked the question (popular but erroneous nomenclature).

2) What Larkin meant by the phrase "A couple of AA batteries can do that!".

3) That two AA cells in series or parallel fall stunningly short of the 2170 J specification cited in Bill's original post.

Note that you didn't ask "Please compare and contrast the short - circuit current performance of a selection of popular AA cells to the short - circuit current capabilities of the 3000 F ultracapacitor cited in Bill Beaty's original post. Determine how many AA cells are required to implement a battery capable of

2170 amps for at least one second, particularly considering ESR and contact resistance. Show your math."

That is literally a different question than "How many cells in the batteries?" , yes?

(...)

"Whoooooooooooooooooooooooooooooooooooooooooooooooooooosh."

Back 'atcha, John. :)

--Winston

That's about what I did, in my youth. Every shot welded the switch contacts, and I'd have to pry tham apart between shots, replace them every 10 or so.

John

(...)

Well, 7 orders of magnitude, but who's counting. :)

And yes, hopefully I would step out of the way.

--Winston

Yawn. You probably think they actually make 'DB9' connectors, too.

Politicians should only get paid if the budget is balanced, and there is enough left over to pay them.

(...)

We are all guilty of using a vernacular term rather than the exactly proper word, at times.

In my case it's largely out of convenience and laziness.

Rather than insist on 'DE-9', I use the erroneous 'DB-9' nomenclature just as thousands of others do. It's quicker.

Accordingly, I suggest that you bring an action against me.

:)

--Winston

"D9" is even quicker, half as many characters, and exposes you to less public abuse.

John

(...)

It can be confusing on delivery, though.

formatting link

:)

--Winston

caps

=A03.04watt-

ith

I
e
e
3kA worth of MOSFETs could switch the thing--that would be fun--but it sort of diminishes the pioneering spirit. We want it, and we want it as crude as possible!

James

 3.04watt-

But mostly we want it to make a very loud noise.

John

be

g.

ew

g.

That's one heckuva FET!

(I guesstimate

e

y be

ng.

new

ng.

Yes! (I ordered a couple. I'd already gotten my own copy of that e- mailed ad and ogled the $15 capsaurus, but had held out successfully until now (no thanks to Bill Beaty for tempting me. :) ).)

When I was a kid there was a cool Scientific American N2 laser project that used a spark gap to nS-switch a massive pulse, discharging a HV FR4 cap--I always thought that was neat.

James

 3.04watt-

A standard IRC catalog part?

Particularly if it makes noise (cue Joerg).

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required