Is she Toast?

[ardbark]

Went down to storage to start prepping the rig this weekend and while checking the water level in the house batteries I found the dreaded white fluff around the bottom edges of the front 6v battery (I have two). Upon closer inspection the sides of this battery were starting to bulge and the top of the battery was wet. Clearly it had boiled over.

The poor girl has sat since last fall, inside, plugged in. Through the winter I went down every couple of months and checked the water level in the batteries, fired her up, exercised the genny, blah blah. But I did not disconnect the batteries, they were on-line the whole time and it is entirely possible I overfilled a cell or two last time I added water. I'm guessing this is what caused the overflow.

I've since neutralized and cleaned the corrosion, plus took the house bats off line, but the bulge is troublesome. Have I toasted that battery?

[bdickson]

Originally Posted by ardbark

Went down to storage to start prepping the rig this weekend and while checking the water level in the house batteries I found the dreaded white fluff around the bottom edges of the front 6v battery (I have two). Upon closer inspection the sides of this battery were starting to bulge and the top of the battery was wet. Clearly it had boiled over.

The poor girl has sat since last fall, inside, plugged in. Through the winter I went down every couple of months and checked the water level in the batteries, fired her up, exercised the genny, blah blah. But I did not disconnect the batteries, they were on-line the whole time and it is entirely possible I overfilled a cell or two last time I added water. I'm guessing this is what caused the overflow.

I've since neutralized and cleaned the corrosion, plus took the house bats off line, but the bulge is troublesome. Have I toasted that battery?

I'd say yes. Any bulge indicates that the internal structure of lead plates held in place by plastic separators has been compromised. Adjacent plates could be touching each other which drastically reduces the efficiency of the battery and could be a fire hazard.

[distaff]

Actually, the bulge may or may not be significant. I have 6 deep cycle batteries and two starter batteries, and the deep cycles are all bulged but work fine.

The battery wholesaler told me that up here where freezing is an issue they see a lot of batteries that are bulged that take and hold charge fine.

[ardbark]

Originally Posted by distaff

Actually, the bulge may or may not be significant. I have 6 deep cycle batteries and two starter batteries, and the deep cycles are all bulged but work fine.

The battery wholesaler told me that up here where freezing is an issue they see a lot of batteries that are bulged that take and hold charge fine.

Interesting statement from your wholesaler, I always heard that a fully charged battery can't freeze.

Regardless, on mine you can see the bulge with the naked eye, but it's not much. I did unplug the coach and turn on all the 12 volt interior lights etc. and everything seemed fine, although it was for only 10 or 15 minutes, not much of a stress test. I'm going down to get the coach this afternoon to top off the fuel and propane, I'll put a meter on it then.

[Libero]

Suggest you test the specific gravity in each cell. (need to get a hydrometer if you don't have one. Any auto supply store will have them and they are inexpensive.)

This is an essential tool/device for wet cell unsealed lead acid battery maintenance. I suspect most rvers with wet cell lead acid batteries carry them. (somewhat useless in AGM or sealed batteries)

If the electrolyte was very low and a charger (depending on type of charger) was on the battery would get hot and could cause a bulge by possibly warping the plates. Very high current charge or high discharge would also cause the battery to get hot.

When batteries charge they emit hydrogen gas which changes the water you put in to Sulfuric Acid (H2SO4). So you are not checking the water level. You are checking H2SO4 which is very toxic and destructive to the skin, eyes clothing fabrics etc if you have not already discovered this. The hydrogen gas of course is extremely flamable so any spark around a charging battery can cause an explosion, so great care is required when messing with batteries.

Good luck, things may seem normal, but something caused that bulge. Good to have the battery checked to be on the safe side IMHO. I witnessed an exploding battery. It can nake a real mess and cause blindness if that acid gets in your eyes.

[ardbark]

Originally Posted by Libero

If the electrolyte was very low and a charger (depending on type of charger) was on the battery would get hot and could cause a bulge by possibly warping the plates. Very high current charge or high discharge would also cause the battery to get hot.

The water level did get low this winter, but not so low that a plate was anywhere near exposed. As for a charger, didn't have it plugged into one, just shore power. I do have a hydrometer, will check each cell as well as voltage at the posts.

Looking forward to next winter, I'm wondering if I wouldn't be better off fully charging them, taking them off line and letting them set. We're at or below 32 degrees for months at a time. There was another recent thread on one of these forums about putting them in your freezer, I don't know about that but I'm pretty sure our winters would slow them down. Till now I've just plugged the coach in over the winter and did monthly checks, running the gen, etc. Never had a problem till now.

[GaryKD]

Hi ardbark,
If it isn't broke don't fix it. If the batteries hold a charge and work as you need them to work, let the sleeping dog lie.

[ardbark]

Originally Posted by GaryKD

Hi ardbark,
If it isn't broke don't fix it. If the batteries hold a charge and work as you need them to work, let the sleeping dog lie.

Now that response I LOVE Just how I think. Of course the corollary is when something does break it will be at the worst possible time in the most inconvenient possible location, do the most damage available thus incurring the highest repair bill imaginable

I'll know more after I go down and test it this afternoon.

[ardbark]

The batteries measured between 1.27 and 1.3 hydro on all cells, 12.75vDc across the array. They've been sitting off line for 72 hours and no new evidence of seepage. Nothing seems to be broke - yet, Gary might have the right of it.

[vsheetz]

Breakdown test OK?
Specific gravity test OK?
Not leaking?
Hold a charge OK?

Then use them...

[ardbark]

Originally Posted by vsheetz

Breakdown test OK?
Specific gravity test OK?
Not leaking?
Hold a charge OK?

Then use them...

+1

[Libero]

I agree if everything tests OK just go with it and keep a close eye on it. Many things could have caused a slight bulge, but something caused the budge and it may well be OK.

Good luck

[ardbark]

Originally Posted by Libero

I agree if everything tests OK just go with it and keep a close eye on it. Many things could have caused a slight bulge, but something caused the budge and it may well be OK.

Good luck

Something *did* cause the bulge and me thinks it was over charging. Wish I could use her more often but work schedules don't allow that - for now.

I'm just wondering if I could be smarter about storing them, clearly something went haywire over this last winter and I have to think about tweaking my routine. Thoughts are welcome

[Afc-Jr]

I have had batteries with a bulge that worked just fine. But it always seems like their life expectancy is not so good after the bulge shows up.

Have also noticed on ours that when I am plugged into shore power for a while the batteries use more water. There must be a tendency to over-charge in the system. Whenever possible I just let the solar panel maintain the batteries and I have never had to worry about them.

Lately I have run across advertisements for battery oil. It looks like a common sense approach to this issue. Has anyone tried this?
Here is the link: Battery Oil from Thermoil Battery De-Mister