On 15 Aug 2005 16:01:44 -0700 wrote:

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

I'm with you; I think this is a complete myth. The conductor theory
completely ignores the fact that they sit on steel while in the cars,
and the concrete dust theory ignores the fact that putting it on a
little square of plywood doesn't change the amount of concrete dust in
the air around it.

My personal theory is that this "problem" just shows up when a battery
is taken out of service and stored in a corner for a long time. Since
any battery will slowly self-discharge at some slow rate, the time
alone is usually enough to explain the fact that the battery is later
found to be dead. Add this to the fact that such batteries are often
already old and possibly from cars in poor condition (poor charging
voltage?) then the prognosis just gets worse.

Any lead acid battery left discharged for long will become sulfated.
This can be easily reversed, but not quickly; it takes time, and most
people won't spend the time. It can take a week or more, but by then
most people have declared it dead and replaced it.

There's also the explanation that the battery dies because the
concrete is cold, thus maintaining a temp gradient across the
electrolyte. Proof of this is claimed to come from the fact that
diesel-electric submarine batteries had active stirrers to keep the
electrolyte at an even temp. I won't claim to know anything about
submarines, but I suspect that stirring would be a very good thing to
keep the electrolyte concentration constant. Otherwise, the
electrolyte concentration would become depleted near the plates and
the battery would appear to be discharged. Stirring the solution,
would make for a much more uniform discharge curve.

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Jim Adney
Madison, WI 53711 USA
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