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.<p>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. <i>That</i> 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.
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).<p>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.)<p>For a battery two dissimilar metals joined by a fluid with ions in it (salt water, acid water, etc.)<p>Make you wonder why it took so long to invent these things, considering they have been made accidentally for millennia.
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).
A ncie combination of food and electronics. Her "candied LEDs" (sugar-encrusted LEDs, see <a href="http://www.emilydaniels.com/2011/08/candied-leds/" rel="nofollow">http://www.emilydaniels.com/2011/08/candied-leds/</a>) reminds me of the glowing crystals in WoW's Marshal's Refuge Cave, as seen in <a href="http://www.flickr.com/photos/r4n/2258496701/" rel="nofollow">http://www.flickr.com/photos/r4n/2258496701/</a> and <a href="http://www.flickr.com/photos/kapowaz/37478022/" rel="nofollow">http://www.flickr.com/photos/kapowaz/37478022/</a>. Fascinating!