p
ho
to
cre
d
it
he
re
Imtra Corporation 30 Samuel Barnet Boulevard., New Bedford MA 02745
508.995.7000
www.imtra.com
The source for today’s most advanced LED marine lighting.
Imtra’s advanced solutions bring innovative excellence to marine lighting. Our LEDs feature superior
control, exceptional color rendering and no radiated heat. To complete your system, we offer Vimar®
switching, the industry’s most popular decorative switching system. We support our products with a deep
knowledge base and unsurpassed customer service. Contact Imtra at 508-995-7000 or visit us online.
Ventura PowerLED
St. Maarten Wall Light Modular Switching System
BATTERY BANK VENTILATION
Steve, I’ve been enjoying your articles
greatly! They are very informative and
professionally presented.
As a do-it-yourselfer, one of my big
problems at present is a large battery
bank that the previous owner had located
in the aft cabin of our 1980 centre cockpit
Gulfstar Sloop. Presently the boat is on
the hard in Green Turtle Cay in the
Bahamas where I’m deep into a major
refitting for blue water cruising.
The present configuration has ( 3) 8D
house batteries.
Although the batteries are in a secured
area I am concerned about gassing and
the health/explosion risks.
It would seem logical to enclose these
batteries in a secured box (using fiberglass
& epoxy for strength and spills) but that
does not take care of the problem of heat
and gassing.
Your article Big Battery Bank - Part
II illustrated that the enclosed area does
not handle gassing or heat build up when
using such a containment.
It would be very difficult to relocate
these batteries and the associated wiring.
Is it possible to use an overboard
venting to remove any build up of gasses
and heat? If so what diameter tubing
would be considered sufficient for the
720 AH of ( 3) 8D batteries (flooded).
Would using rubber hot-water hose
be sufficient or could you recommend a
suitable tubing rigid PVC?
Presumably such an installation would
need to have the box sealed completely
(with Buna?) and if an exhaust fan is used
it would have to be an ignition protected
type.
Your thoughts would be greatly
appreciated. Please let me know if you
require any more details and how I can
compensate you for your time.
John Taylor
Boca Raton, Florid
John, when it comes to battery bank
installation, especially large battery
banks, caution is the order of the day. All
conventional lead acid batteries should
be ventilated, even those that are sealed.
Sealed batteries, if over-charged, will vent
hydrogen gas, which is explosive. Flooded
batteries, on the other hand, vent this gas
regularly during charging. While not very
common, another potential by-product
of battery charging is arsine and stabine
gases, which are toxic. Therefore, battery
banks must be well ventilated. Typically,
this only requires that the highest portion
of the battery box, space or locker in which
the batteries are located be ventilated to
the atmosphere (rather than the cabin).
Because hydrogen gas is lighter than
air, it will rise to the highest location in
a compartment or locker, where vents
should be located.
If you wish to enclose your batteries in
a semi-airtight box or container, you must
consider two issues. One, safe removal
of hydrogen and other gasses and two,
removal of heat, as batteries will generate
heat during charging. The box’s exhaust
Ask Steve
