"Marty S." wrote in message
...
Hi all...
I'm looking for a good
trade-off between the weight of the battery (I'm going to be needing 2
batteries), the reserve time & amps, and cost.


The first thing that you will need to establish is the desired run time on
the motor. If you use standard 27 series deep cycle batteries your run time
at maximum thrust will be under 2 hours, probably closer to 90 minutes. If
you run at less than maximum speed you would probably get two hours or more
from it.

If that is sufficient for your needs then your best bet would be two
standard lead-acid deep cycle batteries. You should be able to pick these
up for $65 to $75 each.

If you need more than that then your best bet would be to use golf cart
batteries. The case size of these are referred to as T-105 or 2200 series.
They are about the same length and width as a standard battery but they are
a bit taller. They are also 6 volts, so you will need four of them. These
batteries are the work horse of the golf cart industry and they are readily
available. Look in the phone book under "battery" and find an industrial
battery supply house. You should be able to find these batteries for under
$70 each.

These batteries will more than double your run time. They should also last
more than twice as many years as the 12 volt batteries will, so overall they
are a sound investment.

Rod McInnis