" bravely wrote to "All" (15 Aug 05 16:01:44)
--- on the heady topic of "Old Husband's tale"

I had it explained to me that the difference in temperature between
the cement and ambient air causes a vertical specific density
difference in the electrolyte. This effect results in an a emf between
the top and bottom of the plates which being conductive allows the
usual battery chemical reaction to take place. Thus the battery
slowly discharges over a period of many months (6 or more).

My thinking is that the black case exacerbates the problem by thermal
emission and perhaps a white case would be less prone to the effect.
BTW I've seen batteries in white cases. Anyhow, one idea I have had is
to cover the terminals with their plastic caps then cover the top with
a plastic bag and wrap the whole battery in aluminum foil. The idea
being to force the battery temperature to be equal between top and
bottom due to the good thermal conduction of the aluminum wrapping.
Perhaps wrapping insulation around the battery would be just as good.
But it's just an untested theory.

A*s*i*m*o*v


ZZ From:
ZZ Xref: core-easynews sci.electronics.repair:339749


ZZ Everybody, and I mean everbody puts down a barrier so when they put a
ZZ car battery down so it's not in contact with the ground, or cement.
ZZ Now normally the battery will sit on steel (in the car) which is a
ZZ conductor.

ZZ They say that being on the ground kills the battery. How does a
ZZ nonconductor (concrete) being in contact with another nonconductor
ZZ cause this ? I refuse to believe it, but I do not put said batteries
ZZ on the ground. (I am a firm believer in Murphy's Law)

ZZ Is this myth or mystery, and if true, just how in the hell can it be
ZZ true. I'm considered pretty advanced when it comes to electronics, but
ZZ this belief is so ubiquitous, that says there might be something to
ZZ it.
ZZ If anyone can shed some light on the process whereby the "ground" can
ZZ discharge a car battery please enlighten me. I've now heard this again
ZZ and have considered buying two brand new car batteries and chargers
ZZ with which to gain empirical evidence. Sometimes when I get curious
ZZ about something I have a hard time letting go of it.

ZZ Can anyone either explain this so I can STFU, or debunk it so I can
ZZ run my mouth ? I've been hearing this for about 30 years now and have
ZZ dropped the subject numerous times. That is no longer good enough.

ZZ Or are we talking about something like the pyramids or whatever ? I
ZZ know some physics but I am by no means a physicist. I'm having a hard
ZZ time believe this "myth" and I would like it cleared up in my
ZZ lifetime, so I asked.

ZZ Thanks to anyone that can set my mind to rest on this annoying
ZZ subject.
ZZ JURB

.... Chico of Borg: "Resistance? Atsa no good!"