Lead-Acid batteries and concrete floors

["VanDerWal, Peter" <vanderwp@fhu.disa.mil>]

I'm sure we've all heard that Lead-Acid batteries will go dead quickly if
you store them on concrete floods (i.e. in the garage).

I'd pretty much assigned this to the "Old Wives" tale section since nobody
could provide me with a credible explanation of why this was so or any
verifiable tests indicating it was true.

Well I was going through some old magazines and I found a letter to the
editor that actually provided a reasonable sounding explanation of why this
happens.  I'm still not sure that they do go dead quicker on concrete, since
I've not heard of anybody testing it, but if they do this sounds like why.

The author pointed out that concrete floors tend to be colder than the
ambient temperature.  I've noticed this, I believe it's due to evaporation.

Anyway with the battery sitting on the floor, the bottom of the battery will
be colder than the rest of it.  This causes temperature stratification of
the electrolyte (different temperature layers).  The different temperatures
in the electrolyte leads to different specific gravity with the colder fluid
at the bottom having a lower specific gravity than the warmer fluid on top.
The different specific gravities will cause different voltage potentials
across the tops and bottoms of the plates.  With different voltage
potentials current will flow inside the battery and cause it to go dead
quicker.

So what do you folks think, sound reasonable?

P.S. If true I would suspect this has less effect on AGMs and Gel Cells.