DH,

You got lots of answers that more or less agree, but there is a small
problem. They are not really complete.

If you need to supply more load than one battery can handle, putting
several in parallel is a good idea.
Problem - even if the batteries are out of the same manufacturing lot,
they are not actually identical in all respects. This means they will
not chargwe the same and if two are in parallel only one will get to
recharge to full capacity. If you want them to all come back to full
capacity, they must be separated and charged individually. This is not
difficult, it just takes switches and thinking to accomplish. Oh, and
probably an individual charger circuit (multi-battery chargers are
available).

Where did I learn all about this? From a man that was a submariner of
WWII. His life had depended on getting the most out of the batteries
and keeping them in good health.

Matt Colie

wrote:
How should more than one battery be hooked together
as a supply for an inverter? Does it matter which battery
in the group the battery charger is attached to? It will
be an automatic charger. Will all of the batteries drain
down and build back up pretty much as one big battery,
if they're connected in the right way?