There is a little known phenomena called electrolyte stratification where a
cold concrete floor can increase the self discharge rate of a lead acid
battery. The bottom layer of electrolyte gets cooled by conduction from the
floor while the upper layer stays basically at room temp. Since there is no
natural circulation to mix the layers, the situation is static and the
increased leakage current flow will eventually discharge the battery.
Diesel-electric submarines had bubbler tubes in their batteries to agitate
the electrolyte . The problem was potentially serious because the batteries
were exposed to very wide temp. ranges in submarine duty.
See http://www.uuhome.de/william.darden/...4.htm#concrete

Randy

"Tom Gardner" wrote in message
. ..
Mom's car, sitting for 2.5 years had to be moved. The Interstate 72 mo.
battery that was put in just before storage won't take a charge...no
surprise, I put another new one in. Rather than turning in the core for
$12
I will get it replaced under warranty. Is there any way to keep a new
battery on the shelf for extended periods of time? Should I keep it on a
trickle charger? Is it an urban myth that sitting on concrete will kill
it?