"Roger Long" wrote in
:

If something does go wrong and one blows up, the acid
impregnated mat in the AGM should be less dangerous and easier to
clean up than the liquid.



Seen it....Acid-soaked glass mat in every nook and cranny. it was
everyplace! What a mess....

"Larry W4CSC" wrote in message
...
"Doug Dotson" dougdotson@NOSPAMcablespeedNOSPAMcom wrote in
:

I agree totally. Liquid lead-acid batterys have a bunch of problems. They
are obsolete technology for boat use. Gel or AGM are far better choices.
Even with a dedicated battery compartment Liquid Lead-Acid batteries
are still dangerous.

Doug
s/v Callista


Drop by a battery shop with the big golf cart batteries. Turn one of 'em
upside down and see what leaks out with the caps on. I dare ya...(c;

I don;t see the point.

The best batteries for a boat are those big, honkin' fork lift batteries,
but most have no place to store that much energy or boat enough to float
that much weight.....

They are called Traction Batteries.

POWER is our friend.

We are talking batteries here, not 2KW RF output from your boat.

What worries me in a glass mat battery is COOLING. The wetcell battery is
cooled by convective currents in the electrolyte. The flow through the
plate separators vertically keeps a constant flow of cooling water
preventing the plates from warping. How do you cool an AGM battery all
wrapped up in INSULATING FIBERGLASS when that big, honkin' 180A alternator
is trying to satisfy a boater who wants to charge the hell out of it for
an
hour to shut down his little diesel, instead of letting it charge SLOWLY
so
it can absorb the energy in its relatively slow chemical reaction to
charging current??

You clearly haven't a clue (as usual). I charge my AGM battery bank at 160A
with no cooling problems (other than the alternator that needs to breathe).

Nope...I like liquid-cooled, hard motion (golf cart or fork lift)
batteries...thanks. EVERY big truck comes with them...Ships, too! I
wonder why??

Wonder why all military vehicles, and aircraft have been using AGM for
years.

I suspect his friend had either a primary wiring short with no fuse link
to
melt, like most boats are wired to the panel, or an internal cell short
out, which is very rare in a modern battery...very rare.

Question - Is he a smoker or could have had something hot near the
charging
cells? There's very little gassing, now that we got rid of the antimony
plate supports, unless he was charging the hell out of it fully charged.

Clearly something whet wrong in this story that was not the fault of the
batteries
regardless of the type of battery or its chemistry.

"Roger Long" wrote in
:

I don't think wet cells have any place on a boat except maybe one that
is
large enough to have a dedicated battery compartment.

-

Er, ah, what kind of batteries do you have that AREN'T "wetcells"?

Gelcells are wetcells....So are AGMs....In the first the acid is jelly. In
the second, the acid is simply absorbed by a gauze-like glass mat in
between the rolled up lead plates.

They're still all lead-acid batteries and will STILL ALL EXPLODE!

Wait until you see a big AGM battery that has an internal short and turns
all that mat into steam!....BOOM! There's nothing holding the plates apart
in an AGM battery.....for all that money....

What was he doing? Checking the water level with a cigarette lighter?

In my experience I have had only one battery explode and it was an AGM my
son had in his car. He had a big alternator to power his obscenely large
stereo amp. When the regulator failed the battery started overcharging and
blew up. Nobody hurt but it cost about $2,200 to replace the hood, grill,
radiator, fender liner and all the hoses.

I will stick to L-16s and recombinant caps thank you.

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

"Roger Long" wrote in message
.. .
While picking people's brains about batteries today, I learned why I
haven't
seen a friend of mine around the waterfront in a while. He isn't in
Florida.
He was bending over the battery in his boat a couple months ago when
it blew
up for no apparent cause. In addition to acid burns, the force of the
explosion threw him against the bulkhead of his boat so hard that he
broke
ribs and punctured his lungs. He's been laid up for weeks.

I don't think wet cells have any place on a boat except maybe one that
is
large enough to have a dedicated battery compartment.

--

Roger Long

Glenn Ashmore wrote:
What was he doing? Checking the water level with a cigarette lighter?

In my experience I have had only one battery explode and it was an AGM my
son had in his car. He had a big alternator to power his obscenely large
stereo amp. When the regulator failed the battery started overcharging and
blew up. Nobody hurt but it cost about $2,200 to replace the hood, grill,
radiator, fender liner and all the hoses.

I will stick to L-16s and recombinant caps thank you.

And I'll stick to Golf cart batteries. At least I can lift them!


Evan Gatehouse

In article , _NOSPAM says...


Glenn Ashmore wrote:
What was he doing? Checking the water level with a cigarette lighter?

In my experience I have had only one battery explode and it was an AGM my
son had in his car. He had a big alternator to power his obscenely large
stereo amp. When the regulator failed the battery started overcharging and
blew up. Nobody hurt but it cost about $2,200 to replace the hood, grill,
radiator, fender liner and all the hoses.

I will stick to L-16s and recombinant caps thank you.

And I'll stick to Golf cart batteries. At least I can lift them!

When the D4s I have in there now start to go bad I think I will sell the boat.