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Thomas G. Marshall Thomas G. Marshall is offline
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Default 50 Dying batteries: Can they be shorted by cardboard if humid enough?

Jack said something like:
So I ran a little test.
Somewhat humid cardboard (sitting in my unheated garage in Seattle in the
middle of winter) measures over 100 megohms on my multimeter.
Sopping wet cardboard (tapwater) measures 1 megohm. Test points 3" apart
although it didn't seem to matter much.

Energizer rated at 2850 mah
Leakage into wet cardboard would be 1.5/1000= .0015 ma.
Time to discharge battery would be 2850/.0015=1.9 million hours or
somewhat
over 200 years.

I suppose the water could have contained more ions than my tap water but
knowing that the human body is quite conductive I also checked the
resistance across my tongue and found it to be 1/10 that of the cardboard
so
it would still take over 20 years to discharge the battery.
I guess I would look elsewhere for the dead battery gremlin.



If you found that it would take 20 years to discharge a battery shorted by
your tongue, I'm suspicious that there's a miscalculation or broken metric
somewhere.


--
Forgetthesong,I'dratherhavethefrontallobotomy...