Growth In The Battery Compartment

[brocki]

In the last 6 months or so I have been having quite pronounced white corrosive looking growth on the steel battery framework in its compartment.  The battery terminal and posts are still squeaky clean with no discernible corrosion on them or in the cable connections.  I am sure that somehow the batteries are the source of this "growth", but not sure why or what to do about it other than just cleaning it off. 

A little history.  The MH is a 10 year old Tiffin Phaeton.  Batteries were bought the summer of 2012.  They have been maintained monthly with only distilled water brought to the line.  The water has never even gotten close to the top of the grids.  The batteries have never been allowed to completely discharge, and when we are on the road, we use a auto gen-start for overnight boondocking. 

Any ideas as to what this situation is telling me and what to do to stop it?

[hermanmullins]

Sounds like you may have an issue with your inverter/charger. Older batteries on their last leg may require deeper charging causing the batteries to out gas. Which can contribute to excess corrosion. 

Herman 

[brocki]

12 minutes ago, hermanmullins said:

Sounds like you may have an issue with your inverter/charger. Older batteries on their last leg may require deeper charging causing the batteries to out gas. Which can contribute to excess corrosion. 

Herman 

But then is that an issue with the inverter/charger or with the batteries?  I have not noticed any increased water consumption.  They use about 4 oz. per cell per month since they were new.  And BTW, is about 5 years an expectable life from good quality 6 volt deep cycle batteries?

[mweiner]

13 minutes ago, brocki said:

But then is that an issue with the inverter/charger or with the batteries?  I have not noticed any increased water consumption.  They use about 4 oz. per cell per month since they were new.  And BTW, is about 5 years an expectable life from good quality 6 volt deep cycle batteries?

Replace them with sealed AGM 6 volt deep cycle batteries. Check out Centennial or Full River.. I agree with Brocki, batteries should be replaced every five years.. 

For ease of maintenance skip the ones where you have to monitor the water levels. 

It's certainly a great idea to check your inverter/charging system at the same time, but, I think it's probably just old batteries. 

[wildebill308]

58 minutes ago, brocki said:

But then is that an issue with the inverter/charger or with the batteries?  I have not noticed any increased water consumption.  They use about 4 oz. per cell per month since they were new.  And BTW, is about 5 years an expectable life from good quality 6 volt deep cycle batteries?

All wet cell lead acid batteries out gas when charging. This will cause corrosion in the area. I would clean the area and wash it down with a baking soda (like you keep in the refrigerator) solution to kill any corrosion then re paint. Especially all the steel that is corroding. Your batteries are geting older but I don't think it is your main problem. To many coaches have adequate corrosion protection  in the battery area.

Bill

[mweiner]

10 minutes ago, WILDEBILL308 said:

All wet cell lead acid batteries out gas when charging. This will cause corrosion in the area. I would clean the area and wash it down with a baking soda (like you keep in the refrigerator) solution to kill any corrosion then re paint. Especially all the steel that is corroding. Your batteries are geting older but I don't think it is your main problem. To many coaches have adequate corrosion protection  in the battery area.

Bill

Bill, I definitely agree, corrosion is a problem....how many times have you seen corrosion with a sealed battery? Probably not very often.?   Sometimes a little at terminals, but nothing compared to a battery with a cap and requiring water. 

[kaypsmith]

If the battery is giving no other problem, I would keep them up as in the past and as Bill suggest, thoroughly  clean up the corrosion with baking soda solution, leave the door open in a dry climate and repaint the area. I have gone to that Flex seal that is advertised on tv and have experienced good results. By the way, silicone caulk is wonderful stuff around windows, plastic, fiberglass and the likes, but is very corrosive on all types of metal, for that reason I try to discourage anyone using it on metal. Of course when the batteries have reached their EOL, it will be a good time to look at AGM batteries. Another tip for battery life and reduction of excessive water usage is desulfation, many charger/inverters have this feature built in, although I think there is another term used for this, just don't remember the term, but is same process. One can google desulfation and find several methods for doing this, it will help with the corrosion issues and extend the battery life.

[desertdeals69]

Most inverter/chargers have an equalize setting which should be done every year or so. You need to completely clean and neutralize all metal and paint with rust preventative paint.  When replacing the batteries, AGM batteries would be my choice because there is no corrosion at the terminals.

[wolfe10]

Be sure the inverter/charger is properly programmed, including temperature (unless you have the optional temperature sensor).

A little puzzling that the terminals and wires are clean, but surrounding metal has the "growth". That would suggest that either there is a leak in one of the batteries OR an electrical issue between chassis and battery ground.  Yes, if resistance between "metal of the coach" and battery bank negative terminal, it can cause an electrical current and "growth"

SO, check that all connections between chassis and battery negative are clean and tight.  If the "growth" re-appears, pull the batteries and check them individually.

Yes, one of the reasons in our coach and boats I use Lifeline AGM's.  Guess there are some others on the market now, but we were introduced to the Lifelines on our 1995 Pacific Seacraft  Crealock 37' as standard equipment and have found the "up-charge" a good decision ever since.

[hermanmullins]

Brocki, 

I would consider 4 oz per cell per month seems a bit excessive. And as Brett said it is strange that the terminals and cables aren't corroded. 

Herman 

[wildebill308]

As Herman pointed out that is a lot of water. I would see if the charge circuit is set up right and if it has the float charge feature. It does sound like it is "boiling" the batteries creating more outgassing than normal and hence the corrosion. This will shorten the life of the batteries. Here is a link to more than you ever wanted to  know about Batteries. 

http://www.trojanbattery.com/tech-support/battery-maintenance/

Kay, here's a link about desulfation.

http://www.chargingchargers.com/tutorials/battery-desulfation.html

Bill

[brocki]

Thanks guys for the information and thanks Wildbill for that websight.  Even though I  have been doing most of those steps for years, having the info and tables is valuable.  I will start by giving them an equalizing charge tonight.  Haven't done that for a couple of months.  Brett, I will test out that potential voltage difference right away (maybe not today, it is supposed to rain soon).  I will do another cleanup soon but don't know how well I can repaint as I'm not sure I can muscle those batteries out of their nests.

The batteries have not shown any reduced ability to provide power when needed, aka; short cycling on the generator when boondocking.  For that reason, I won't be putting replacement in the budget soon.  They still run the wife's C-pap machine all night with no trouble.  Thanks again for the help.

[wildebill308]

6 hours ago, brocki said:

Thanks guys for the information and thanks Wildbill for that websight.  Even though I  have been doing most of those steps for years, having the info and tables is valuable.  I will start by giving them an equalizing charge tonight.  Haven't done that for a couple of months.  Brett, I will test out that potential voltage difference right away (maybe not today, it is supposed to rain soon).  I will do another cleanup soon but don't know how well I can repaint as I'm not sure I can muscle those batteries out of their nests.

The batteries have not shown any reduced ability to provide power when needed, aka; short cycling on the generator when boondocking.  For that reason, I won't be putting replacement in the budget soon.  They still run the wife's C-pap machine all night with no trouble.  Thanks again for the help.

If you don't want to pull the batteries you can sprinkle some baking soda around them to kill the acid. DO NOT get any in the batteries or it will kill the batteries.

Bill 

[tbutler]

As to the life of the batteries, yours are approaching 5 years.  My experience with 6V wet cell batteries has been they die in about four years.  In my experience, they never gave me any warning, just quit taking a charge and went dead.  I switched to the sealed AGM batteries in 2014.  This is the fourth summer on the road for those batteries.

[brocki]

I didn't get to work on them today but tomorrow looks good to try to do some extensive clean up and Brett's suggestion on voltage to ground.  I have a fairly new digital multimeter so I should be able to get an accurate reading.  I haven't taken any specific gravity readings in a long time.  A good look at some of those cells should give me a better indication of future life.  I really would like to have them last until next spring.

And I will be very careful during the cleaning process.

[rsbilledwards]

The charging style will increase the life span or reduce it. I expect 7 to ten years from the Crown 260 6 volt batteries currently in the coach. I will admit that the 12 volters in the Zanzibar lasted 3 to 4. Most of the inverters of years past are not set nor designed to charge as currently determined ...technology moves forward and most folks do not spend to keep up and expect the old style units to automatically do what newer components do. Because one spent a lot of money, does not mean he got the latest and the greatest either. It also does not mean that the appropriate programming was done either if later technology is installed...It is up to us to figure it out. One can not blame it all on the batteries.