On 8 Nov 2005 20:14:50 -0800, wrote:

Popular widsom has it that the batteries should be removed from the
boat before winteer storage. The boat will be stored outside, here in
Montreal,.

Question is, why can the batteries not be left in the boat if they are
fully charged before the winter and charged again in the spring?


Briefly, because batteries discharge somewhat directly to the air, and
if still hooked up to wire...even a discontiniuous circuit...will
"leak". That's why boats "put away" are recommended to disconnect the
ground.

The cold...and in Montreal, very cold...weather also lowers the
voltage rating of batteries significantly, perhaps to the point of
allowing the electrolyte to freeze.

Having said that, I keep mine aboard, but I charge them twice a week
as I live near to my club and have a tarp, heater and 15 amps to the
boat 16 hrs/day if I need it. I will deliberately run the cabin lights
or a small inverter to cycle them over the winter a couple of times on
the perhaps dubious theory that a battery bank being used and charged
is happier than a bank being half-frozen and then jolted with a
charger on occasion.

If you are leaving your boat entirely, standard battery preservation
lore has it to bring them home to a cool basement and trickle charge
them (assuming they're standard lead/acid "wet" cells) a couple of
times a month at 14.1 volts or so to "top them up".

R.

Also a low volt battery (from sitting) has a good chance of freezing
and busting. thus electrolite drained all inside the boat, that is
unless you're battery is encased in a battery box, and that's still no
garentee.

PLUS a battery will normally loose 3-4% of it's rating per month due to
natural deterioration, and by letting it sit idle in low temperatures,
will cause it to deteriorate at a quicker rate.

Yes, if you are going to store your boat for the winter, I'd suggest
taking the battery completely out and storing it inside if possible.

My friend lives in an appt. complex and cannot do such, so, he goes to
an extreme. he switches the battery in his pick up truck and boat
battery every couple weeks in the winter.

Yeah, like I said thats an extreme, but he doesn't seem to have much of
a problem with batteries being consistantly charged.