exploding battery

[JusDreaming]

I have a battery for the generator, which is located in the transom steps. Which on our boat is a seaLed crash compartment.
Well the other morning we hear a bang!! I checked every where and could not find anything out of place. So I checked the generator compartment. Well evidently there had been a spark and the gas from the battery had accumulated in the sealed compartment. Well the sound we heard was the top of the battery being blown off. It had exploded!!!!!!! The only thing funny was when Diane ask if the battery was still under warranty My response was, "no darlin when you blow the top off of it, it basically voids the warranty"

[Just a Tinch]

OUCH!! At least it was confined to that space. Batteries have a tendency to give off hydrogen when they "gas off"...or while charging....its kinda "explosive". Happy y'all weren't hurt or that there wasn't more damage!!

[never monday]

DENNY!!!!!

[JusDreaming]

now for suggestions on how to vent that area. Or should I think abut relocating the battery? Pat you know the boat any suggestions?

[never monday]

how about dropping the $$$ for an AGM?
or move the battery into the engine room.

[JusDreaming]

are agm the only one which don't produce gas? This was a no maintenance, so I assume itwas a gel?

[never monday]

Where is Rick...I'm not an "expert" in this field.

[Alan Wheeler]

It depends on the battery. Not all AGM and Gel batteries are created equally. Some are sealed, some cheat and are not.

Batteries should be considered as explosive gas producing and should be stored as such. Just like the LPG tank. The battery box needs venting to outside air. The only difference between LPG and Battery gas is, hydrogen is lighter than air and will rise. LPG is heavier and sinks. So a battery box needs venting so gas accumulating at the top of the box vents to outside.

Denny, I wouldn't rule out the warranty issue just yet. For the battery itself to explode, then the arc would have had to be internal. External would have demolished the battery compartment, not the battery. External would probably have been a heck of a lot bigger bang as well. But for the top to be blown off, the gas would have had to be ignited from the inside.

[Fishspearit]

Originally Posted by Alan Wheeler

Denny, I wouldn't rule out the warranty issue just yet. For the battery itself to explode, then the arc would have had to be internal. External would have demolished the battery compartment, not the battery. External would probably have been a heck of a lot bigger bang as well. But for the top to be blown off, the gas would have had to be ignited from the inside.

That's an interesting point.
'Maintenance Free' on the lead acid batteries I've seen often means that you just can't remove the caps and add water. Have you got any pictures?

[hellosailor]

"This was a no maintenance, "
That almost always means a 1970's-vintage design, where they simply use lots of extra electrolyte and vents that don't leak much, so there's "extra" electrolyte onboard and when it is gone--no maintenance is possible.

An AGM or gel would say something about "SLVR" or "Sealed Valve Regulated" or some similar combination on it. The charging voltage for AMGs and gels may differ, also, you can blow up a gel battey by charging it using wet lead battery settings. Or, simply as they age and dry out.

I'd agree with Wheels-don't ignore the warranty, hydrogen and a spark is NOT the only reason batteries explode. I've had two sets (presumably one gel, one AGM) literally burst their casings in UPSes under "normal" conditions.

[David M]

I have had a battery blow up. The best you can do is have a box with a vent on the lid and realize that the faster you charge, the greater the rate that it creates hydrogen.

[avazquez]

The batteries on my sailboat are under the companionway steps in front of the engine. Pretty much inside the boat. I have lead acid and they are open to the engine compartment. What would be the safest way to go in terms of battery selection???

[David M]

Originally Posted by avazquez

T I have lead acid and they are open to the engine compartment.

Do you mean it is not in a battery box? By all means, get it in a battery box with a strap over the lid. You don't want acid blown all over your engine space should it explode.

[Alan Wheeler]

Trust me, you will never contain a battery when it goes bang. In fact, I suspect the more you try to contain it, the worse the pop! Hydrogen is the biggest bang for buck gas you can get. I do agree with containing the acid however and certainly a plastic battery box is still worth the effort. The acid will soak everywhere and wreck everything it comes in contact with. But do expect the battery box may also go the same way as the battery casing if the bang is big enough.

[avazquez]

Originally Posted by Alan Wheeler

Trust me, you will never contain a battery when it goes bang. In fact, I suspect the more you try to contain it, the worse the pop! Hydrogen is the biggest bang for buck gas you can get. I do agree with containing the acid however and certainly a plastic battery box is still worth the effort. The acid will soak everywhere and wreck everything it comes in contact with. But do expect the battery box may also go the same way as the battery casing if the bang is big enough.

So what is the best solution? Diferent batteries? Separate fiberglass compartment?