Exploded Battery!

[Flatfive]

Last night around 9 PM, we heard what sounded like a gunshot. Went out and looked around. No clues. This morning I see that one of the two 12V batteries on the tongue of my 20 ft trailer had exploded! It's continually being charged by a good quality, computer-controlled converter so It shouldn't have been being over charged.

Just yesterday, though I did disconnect the cables one at a time and clean the connections with sandpaper. Then I replaced them, again, one at a time, and greased them so as not to get corroded again. I did this because the batteries were running only 9 volts even though they were connected to the converter for a month. I was figuring they couldn't get charged through the corroded connections.

Any clues as to what the problem is?

[Dtank]

opnspaces wrote:
Did you check the water level in the batteries while you had them disconnected? My guess is the exploded one had a low cell and the charging made it spark internally.

Knew of two instances of the above. Both were with factory original batteries in a *(not sure of the Japanese import name -it's been a while)*.

Both were owned by conscientious folks who took good care of their vehicles.

.

[Matt_Colie]

To answer all the questions raise since I answered.

Many more boats use a pair of GC2s for the house bank because they work better and last longer. If the boat can manage the weight, it is a good idea.

As to "Marine" batteries, they are just a compromise between a deep cycle (that they are not) and a good starting battery (that they are also not). If is a house bank and you want to run 2 each 12V Jars (old battery talk from when they were just "jars", (but I am old too, so it fits and it is a shorter word), and strap (meaning connect them - we used to do this with copper straps) them in parallel, then you should also be aware that unless they came off the line one after the other, you will never get capacity X 2. If you are lucky you might get 1.75. They do not play well in parallel.

I have only ever seen one explosion in a bank of 6Vs. That one actually burned a terminal when the owner cross to the house bank onto the main engine battery to try to start an engine that really needed the fuel system bleed correctly.

A very big advantage to me with the paralleled 12V set up is that if one cell in one jar goes bad, an explosion is almost certain and I get paid good money to clean up the mess.

Matt

[pianotuna]

Grit dog wrote:

Matt_Colie wrote:
I am a small boat sailor and a licensed ship's engineer that retired and has been doing work on other people's boats for most of the last twenty years. Most now have a house bank that is a pair of GC2s (golf kart batteries). Some still have pairs of 12V jars. I have seen and cleaned up after many more battery explosions that were pairs of 12V jars. If you believe the convenience of two 12V is worth it, carry backing soda on hand as a precaution.

Matt

So a 12V has some inherent propensity to explode that a 6V doesn’t??
Roflmao

Yes. The plates are thinner which leads to thinner separators, often with smaller debris reservoirs, so dendrites penetrate sooner. Shorted cell and aggressive charging do the rest.

[Grit_dog]

Matt_Colie wrote:
I am a small boat sailor and a licensed ship's engineer that retired and has been doing work on other people's boats for most of the last twenty years. Most now have a house bank that is a pair of GC2s (golf kart batteries). Some still have pairs of 12V jars. I have seen and cleaned up after many more battery explosions that were pairs of 12V jars. If you believe the convenience of two 12V is worth it, carry backing soda on hand as a precaution.

Matt

So a 12V has some inherent propensity to explode that a 6V doesn’t??
Roflmao

[mr_andyj]

Matt_Colie wrote:
I am... I have seen and cleaned up after many more battery explosions that were pairs of 12V jars. If you believe the convenience of two 12V is worth it, carry backing soda on hand as a precaution.

Matt

I have never seen any RV on here call anything a jar...

Are you saying boaters use golf cart batteries more over marine? or are you saying it is exactly half and half 50/50 and most of the issues are with GC batts, not marine?

It's like the news saying, there are more cases, but ignoring that there is also more testing to reveal more cases that were not revealed when there were less cases. Stop testing, we will have zero cases...

[PastorCharlie]

I would recommend mixing a good solution of baking soda in water and spray the area all around the tongue and front of camper to neutralized the acid that was sprayed on the camper from the battery explosion.

[frankwp]

I experienced a hydrogen explosion when I connected a jumper cable to the battery post. I was a dumb teenager at the time, but also a lucky one because I didn't get hurt. It wasn't a major event, but it sounded like a gun shot, blew all the caps off the battery, & scared the **** out of me. That was a lesson learned.

[Matt_Colie]

I am a small boat sailor and a licensed ship's engineer that retired and has been doing work on other people's boats for most of the last twenty years. Most now have a house bank that is a pair of GC2s (golf kart batteries). Some still have pairs of 12V jars. I have seen and cleaned up after many more battery explosions that were pairs of 12V jars. If you believe the convenience of two 12V is worth it, carry backing soda on hand as a precaution.

Matt

[Chum_lee]

CA Traveler wrote:
Shorted cell - boom!

Replace the other battery also. Might be educational to have it load tested but it's toast.

Yep! To the OP, you don't state if your batteries are inside a box or not. If they are inside a box, make sure that there is adequate ventilation.

Chum lee

[azdryheat]

Co-worker was sitting in a golf cart at work when one its batteries let go. The bang sounded like a bomb. Turns out our golf carts aren't properly maintained.

[ajriding]

Same for your car battery. Keep the water topped of and use distilled water only.

Agree on two 6 volt batts if you have room. Marine 12v batts are not the right choice for an RV, they are an ideal compromise for a boat to start the gas motor, and be able to run the electric trolling motor a little, then start the gas motor again. Otherwise they are not great.
I dont know why the RV industry uses them, or how that got started...

[pianotuna]

If you can afford them consider SiO2 batteries.

As others have said one cell shorted. That probably caused all the other cells to gas (not boil). Once the hydrogen so created got exposed to an ignition source. *BOOM*

[KD4UPL]

A battery at 9 volts is probably bad and should have been replaced. Do you ever check the water in the batteries? I'd bet they ran dry.

[wa8yxm]

One of the big arguments in forums like this is
Which is better
2 six volt in series
or 2 12 in parallel
Well... There are dangers with both hookups and you just found the parallel danger. If one of the batteries develops a shorted cell...or two. the other battery will very rapidely try to charge teh remainingi cells and KABOOM.

NOTE. There are dangers with the two six in series two. I'd rank them roughly equal so the moral of this post is "Whatever occupies your trailer tongue is good" at least up to this point.

I prefer the six volt pairs myself. but that is a topic for a different thread.

Finally.. You need to replace both batteries. and you might think about converting.. WHY? More amp hours for less $$$$ and more still USABLE amp hours.

Down side. More work and taller batteries may not fit.