The oxide
breaks down whenever the capacitor isn't
powered, but it is an exponential decay effect. Leaving something
powered off a short while doesn't let it break down too much, and when
you power it up again, the oxide reforms a little bit, back to where it
is supposed to be.
I'd like to see some data/research that supports this.
Well, this doesn't specifically mention the "exponential decay effect",
but will this help?:
http://electrochem.cwru.edu/encycl/art-c04-electr-cap.htm
"[...] the capacitor "fill" electrolyte continues the healing work of the
original forming electrolyte, repairing and thickening the dielectric
locally as required. This healing process is driven by the capacitor's dc
leakage current, which is drawn whenever a dc voltage is applied to the
capacitor, that is, whenever it is in operation. In fact, electrolytic
capacitors often last longer when they are in continuous, mild use that
when they are only charged up briefly every year or decade."
Feel free to read the entire article if you like, and/or check out some
of the links towards the bottom. (I found the Cornell Dubilier article in
"Further reading" particularly helpful to me when I needed a good general
overview, but alas the link is broken. It's still on the CDE site, though,
at
www.cde.com/catalogs/AEappGUIDE.pdf .)
-O.-
