mwtilden@watmath.waterloo.edu (Mark W. Tilden) (01/10/91)
At my surplus store I recently found these incredible
capacitors which deliver 47000uF in a small thimble-sized
can (max 5.5v). They also had 1.0F caps about the size of an
oreo cookie. These are neat, but I need more of them in different
ranges and sizes (around 2000uF to 20000uF). Anyone know where
to obtain? Thanx in advance.
As an aside, does anyone have information on how these things work?
I haven't sliced one open yet for fear of toxicity.
Is all.
--
Mark Tilden: _-_-_-__--__--_ /(glitch!) M.F.C.F Hardware Design Lab.
-_-___ | \ /\/ U of Waterloo. Ont. Can, N2L-3G1
|__-_-_-| \/ (519) - 885 - 1211 ext.2454,
"MY OPINIONS, YOU HEAR!? MINE! MINE! MINE! MINE! MINE! AH HAHAHAHAHAHAHAHAHA!!"henry@zoo.toronto.edu (Henry Spencer) (01/10/91)
In article <1991Jan9.200343.12783@watmath.waterloo.edu> mwtilden@watmath.waterloo.edu (Mark W. Tilden) writes: >capacitors which deliver 47000uF in a small thimble-sized >can (max 5.5v). They also had 1.0F caps about the size of an >oreo cookie... >As an aside, does anyone have information on how these things work? If they're the ones I'm thinking of, they are made by taking a conductive powder, packing it loosely so there are lots of pores, and then treating it to make the surface a dielectric. The powder is one electrode, and a conductive material filling the pores is the other. The enormous surface area inside the pores is what gives the massive capacitance. A consequence of this setup, however, is that internal series resistance is quite high, which limits the applications to ones in which frequency response is not an issue. They are primarily battery replacements for keeping nonvolatile memories alive. Don't use them as filter capacitors, they aren't built for it. You might even overheat them. -- If the Space Shuttle was the answer, | Henry Spencer at U of Toronto Zoology what was the question? | henry@zoo.toronto.edu utzoo!henry