Larry (or whoever else jumps in),

I know there was a recent thread on this but Google didn't turn up the
clear answer I'm looking for.

I know it's theoretically better to keep batteries on a trickle charge
and warm over the winter but it costs me $70 to have them taken out of
the boat and stored by the yard. (Nevermind the reasons why I don't
want to take them out myself and home to my basement.)

I've got a good three stage charger in the boat. If I put a good
charge on my two AGM's just before the shrink wrap goes on and leave
them till early spring with no further attention, will I have reduced
their life and strength enough that the $70 would have been a good
investment? If the difference between warm, charged, and dead, cold
storage is just around the theoretical margins, I'm inclined to leave
them in place this year.

I'm in Maine which isn't quite as cold as people think, at least on
the coast. These two year old batteries get pretty light use with a
15 hp diesel, a few lights, and frequent dockside charging from shore
power. I don't leave the charger on all the time so they don't micro
cycle but they seldom get pulled down very far either.

--

Roger Long

On Sat, 28 Oct 2006 13:02:20 GMT, "Roger Long"
wrote:

I've got a good three stage charger in the boat. If I put a good
charge on my two AGM's just before the shrink wrap goes on and leave
them till early spring with no further attention, will I have reduced
their life and strength enough that the $70 would have been a good
investment? If the difference between warm, charged, and dead, cold
storage is just around the theoretical margins, I'm inclined to leave
them in place this year.

Shouldn't be a problem. Most folks with really large batteries like
8Ds do that because they are too much trouble to wrestle on and off
the boat.

After your final charge in the fall I'd recommend removing the battery
cables to eliminate all possibility of a leakage path.

Recharge promptly in the spring at first opportunity.

Roger Long wrote:

I know it's theoretically better to keep batteries on a trickle charge
and warm over the winter but it costs me $70 to have them taken out of
the boat and stored by the yard. (Nevermind the reasons why I don't
want to take them out myself and home to my basement.)

....
I would vote in the "no-problem" camp. The self discharge rate of
AGM's is very low, and in the winter temps should be a quarter of the
summer rate, or less. If you're able to visit the boat a few times,
you should check the voltage to make sure nothing as gone awry. And a
small solar panel might not be a bad investment

In my case, I have a solar panels (150W) under the shrinkwrap that
keeps a small charge on the large flooded house bank. The AGM starter
bats (Optima red top) can fend for themselves.

"Jeff" wrote in message
. ..
...

In my case, I have a solar panels (150W) under the shrinkwrap that keeps a
small charge on the large flooded house bank. The AGM starter bats
(Optima red top) can fend for themselves.


150 watt solar panels? Who makes them? And they work installed under the
shrinkwrap?

Eisboch

"Jeff" wrote in message
. ..
Roger Long wrote:

I know it's theoretically better to keep batteries on a
trickle charge
and warm over the winter but it costs me $70 to have
them taken out of
the boat and stored by the yard. (Nevermind the reasons
why I don't
want to take them out myself and home to my basement.)

...
I would vote in the "no-problem" camp. The self discharge
rate of
AGM's is very low, and in the winter temps should be a
quarter of the
summer rate, or less. If you're able to visit the boat a
few times,
you should check the voltage to make sure nothing as gone
awry. And a
small solar panel might not be a bad investment

In my case, I have a solar panels (150W) under the
shrinkwrap that
keeps a small charge on the large flooded house bank. The
AGM starter
bats (Optima red top) can fend for themselves.


*Under* the shrink wrap? I though solar panels had to get
direct sunlight.

SBV

Eisboch wrote:
"Jeff" wrote in message
. ..
...

In my case, I have a solar panels (150W) under the shrinkwrap that keeps a
small charge on the large flooded house bank. The AGM starter bats
(Optima red top) can fend for themselves.


150 watt solar panels? Who makes them? And they work installed under the
shrinkwrap?

They are three 50 watt panels, on the hardtop. On a sunny day, they
do get into "charge" mode. I've never read the exact current, but
perhaps this winter I'll have a chance because I have a new charge
controller that reads the current.

Also in the late winter, I cut a hole in the shrink over one of the
panels, and from that point on there is plenty of juice

Scotty wrote:


*Under* the shrink wrap? I though solar panels had to get
direct sunlight.

There is certainly some attenuation. But if direct sunlight can give
me 8 Amps, its not unreasonable to get one Amp with the cover on.

If you had a small portable panel, it should obviously be mounted
outside the wrap.

"Jeff" wrote in message
. ..

Eisboch wrote:


150 watt solar panels? Who makes them? And they work installed under
the shrinkwrap?

They are three 50 watt panels, on the hardtop. On a sunny day, they do
get into "charge" mode. I've never read the exact current, but perhaps
this winter I'll have a chance because I have a new charge controller that
reads the current.

Also in the late winter, I cut a hole in the shrink over one of the
panels, and from that point on there is plenty of juice


Cool. I had a single, 50 watt panel on an RV. Direct sunshine produced
slightly over 2.5 amps.

I thought you had a single, 150 watt panel and was curious where you got it.

Eisboch

The best source that I found for solar panels is Wholesale Solar.

http://www.wholesalesolar.com/

The prices were so cheap that I was almost afraid to use them. I did
and have been very please with them.

-Lee

Eisboch wrote:
"Jeff" wrote in message
. ..

Eisboch wrote:


150 watt solar panels? Who makes them? And they work installed under
the shrinkwrap?

They are three 50 watt panels, on the hardtop. On a sunny day, they do
get into "charge" mode. I've never read the exact current, but perhaps
this winter I'll have a chance because I have a new charge controller that
reads the current.

Also in the late winter, I cut a hole in the shrink over one of the
panels, and from that point on there is plenty of juice


Cool. I had a single, 50 watt panel on an RV. Direct sunshine produced
slightly over 2.5 amps.

I thought you had a single, 150 watt panel and was curious where you got it.

Eisboch

"Roger Long" wrote in news:wxI0h.11440$0L1.9288
@twister.nyroc.rr.com:

These two year old batteries get pretty light use with a
15 hp diesel, a few lights, and frequent dockside charging from shore
power. I don't leave the charger on all the time so they don't micro
cycle but they seldom get pulled down very far either.



I don't advocate constant charging on batteries that are stored. I
recommend a SIMPLE automatic shutoff charger put on them overnight ONCE a
month during the storage period, with the batteries completely disconnected
so there's little external leakage over the dead period...just disconnect
their terminals. ONE a month, not a continuous trickle which usually
results in them gassing with a little overcharging, no matter how much a
boat dealer charged for the chargers...(c;

As to pulling them.....they should be stored ABOVE 0C, so there's no
possiblity of them freezing, even if discharged inadvertently. AGMs and
gelcells have no place to expand to all wadded up like they are so anything
the might freeze them will simply destroy them. If the boat's going to sit
on the hard with no internal heat in -20F winter...pull 'em.

Another factor might be a self-preservation issue. Batteries are always
subject to internal shorting...and subsequent explosions. If anything
warps a plate...like really cold weather...a simple plate-plate short will
blow the thing apart, turning the acid electrolyte into a steam explosion,
distributed evenly over everything left in the boat.

You have to weigh that $70 against this Worst Case Scenario....It's your
call...(c;

(If you ever get a chance to look around in a boat the battery exploded
inside of, please take the time to look around. It never ceases to amaze
me how it can etch a fork buried in a tightly closed drawer on the other
end of the boat from that battery!)

--
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If you're sending someone some Styrofoam,
what do you pack it in?