BC> The one I use is a Power Sonic PS-1220, 2.0 amp hr 
 
The Power Sonic is an absorbed electrolyte gas recombinate lead acid battery
which is older but much better technology than the gel cell. It is a true
deep cycle battery which can be charged up to 14.7v same as your car battery.
If you did that to a gel cell, it would die very quickly. Gel cells start
drying out at about 13.6v. Put a meter on your car system with the engine
running and you will see the voltage is usually over 14v. Most of the dealers
don't know the difference, but batteries like the Power Sonic will give a
lot longer service than gel cells.
                               Richard
... It's 11PM. Do you know where your FBI file is?
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