On 15 Aug 2005 19:35:51 -0700 wrote:

2. A reaction between whatever solubles are in or on the cement, along
with the highly acidic content of the battery housing, which has some
porosity, is an interesting possibility.

The case is not acidic, so case contact with the floor can't be the
problem. Reaction of the acid with something from the floor that gets
in the air and then into the battery MIGHT be a possibility, but then
the people who say this happens, also claim that just putting the
battery on a small square of wood (on top of the concrete) prevents
the problem, even though it would not change anything that comes off
teh concrete and gets into the air.

3.Basement floor : While copper is an excellent conductor, cement is
not. That is not to say it is a good insulator. Your legs act as wires,
not very good wires, but functional enough to kill. If you are barefoot
on cement, it's not making all that good of a wire either, but look at
your footprint and you see the cross-sectional of this wire. A bit
bigger than the wires in your basic 12-2 Romex you think ? A copper
conductor of that size could carry thousands of amps. It needs alot
less to burn you, or to discharge your puny battery over time.The
linear resistance of a piece of wire is inversely proportional to it's
cross sectional area. So what do we have here, how many ohms ?

There is certaily self discharge between the battery posts, and
keeping the top of the battery clean minimizes this. Dirt and moisture
on the battery case will decrease the resistance and increase the rate
of discharge. Putting the battery on moist concrete will make this
slightly worse, but putting it on the steel battery tray in the car
would be even worse, contrary to what is reported.

Actually I would be at a disadvantage here with my 13 wide sized feet.

;-)

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Jim Adney
Madison, WI 53711 USA
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