Tom,
Please be advised that boating laws do not specifically require a battery to be
in a box. What they do require is a battery to be securely mounted and the
"non-grounded" terminal covered. Most folks interpret that as a battery box or
bracket to old the battery in place. Most folks usually cover both battery
terminals, as interpretation of the terminal issue varies state to state and
officer to officer.
Battery boxes as used in boating are generally vented, by the cable
entrance-ways and some even have a small open vent on the top. If a battery is
placed in an enclosed compartment, it is generally vented externally or via
another compartment. I do not recall the precise position of the ABYC on
battery ventilation, but I know they require the battery not be mounted under
any electronic or electrical equipment for the sake of corrosion.
In the past, I have used marine type battery boxes for radio installations and
I usually vented it outside by cutting a hole in the battery box top and
affixing a flexible vent line to the outside. I have experienced no
complications following this procedure, either with corrosion or explosive
events.
Good Luck,
Rich
N9EMS
