

Sweet n' Salty Capacitor - wollw
http://www.emilydaniels.com/2011/10/sweet-n-salty-capacitor/

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sbierwagen
They can't be pure capacitors, otherwise the charge would be leaking away. No
capacitor in the world is going to be reading .6v three days after being
charged to 9v.

Also, the paragraph about the piezoelectric effect in salt is incoherent
nonsense. There could be a plausible electrochemical effect causing a change
in the output voltage when the cell is heated; but the .1v change resulting
from vibration has to be pure measurement error. _That_ is quite plausible,
since she's using a three digit hardware-store multimeter, and .1v is the
smallest possible change it can measure in the 200 volt (?!?! 200 volt mode
when measuring the voltage of an electrochemical battery?) range mode.

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ars
Cute and looks sort of yummy. The science is a bit lacking though (the
vibrations have nothing to do with anything, except maybe plate separation on
the capacitors).

You can make a capacitor (or battery) out of virtually anything. For a
capacitor two conductors separated by an insulator - any conductor - any
insulator - any shape. (Obviously some will work better, but all will work.)

For a battery two dissimilar metals joined by a fluid with ions in it (salt
water, acid water, etc.)

Make you wonder why it took so long to invent these things, considering they
have been made accidentally for millennia.

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avian
I'm not familiar with the chemistry she is using, but since the surface area
of her electrodes is very small I think it is more likely that this works as a
rechargeable battery (an electrochemical cell) than a capacitor (storing
energy in an electric field between electrodes).

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zokier
In addition to small surface area, the distance between the electrodes is very
large, which would make it even worse capacitor.

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Luyt
A ncie combination of food and electronics. Her "candied LEDs" (sugar-
encrusted LEDs, see <http://www.emilydaniels.com/2011/08/candied-leds/>)
reminds me of the glowing crystals in WoW's Marshal's Refuge Cave, as seen in
<http://www.flickr.com/photos/r4n/2258496701/> and
<http://www.flickr.com/photos/kapowaz/37478022/>. Fascinating!

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jluan
If this actually works as a cap, somebody should build a guitar amp out of it.

~~~
zokier
How do you build a (guitar) amp with a capacitor? Filter I can understand, but
an amplifier?

