Corrosion on House Batteries

[OldForester]

We have recently incurred a problem with our '06 with white corrosion or a white sulfate-like deposit occuring on the house battery hold downs and attaching bolts. Reminds me of the deposits we used to see on the old days on car battery connections.

I did my old-time remedy of cleaning the deposits with a baking soda/water mixture and lightly covering the area where they occurred with chassis grease. This works, but it causes deposits to move to another area of the hold-down brackets or another bolt. The grease also attracts dust, requiring more cleaning.

I'm curious as to the root cause of this -- is it a case of overcharging the batteries (I am plugged in to AC when stored, and the batteries quickly go to "float" stage on the Xantrex display), or is it some other problem?

I also notice the rear batteries get a little damp around the caps and hose connections, so I'm wondering if they are getting a little overfull and if this dampness is contributing to the problem.

My gut feel is that there's some electrolytic-type process going on with the charging that's causing the deposits on the metal brackets, perhaps a ground cable from a battery touching a bracket where I can't see it, or something else.

So, any ideas from the group on root cause and what to do to stop this problem?

Thanks for your thoughts on it --

[OldForester]

We have recently incurred a problem with our '06 with white corrosion or a white sulfate-like deposit occuring on the house battery hold downs and attaching bolts. Reminds me of the deposits we used to see on the old days on car battery connections.

I did my old-time remedy of cleaning the deposits with a baking soda/water mixture and lightly covering the area where they occurred with chassis grease. This works, but it causes deposits to move to another area of the hold-down brackets or another bolt. The grease also attracts dust, requiring more cleaning.

I'm curious as to the root cause of this -- is it a case of overcharging the batteries (I am plugged in to AC when stored, and the batteries quickly go to "float" stage on the Xantrex display), or is it some other problem?

I also notice the rear batteries get a little damp around the caps and hose connections, so I'm wondering if they are getting a little overfull and if this dampness is contributing to the problem.

My gut feel is that there's some electrolytic-type process going on with the charging that's causing the deposits on the metal brackets, perhaps a ground cable from a battery touching a bracket where I can't see it, or something else.

So, any ideas from the group on root cause and what to do to stop this problem?

Thanks for your thoughts on it --

[C&H from NorCal]

I used baking soda until I found a blue colored chemical at a battery shop that I spray on then rinse off and it does a lot better job in one application than the baking soda did in several. I also bought a spray can of red battery corrosion preventer. It can also be bought at Walmart. Since using these two items I have a had a lot less corrosion. I still get some around the hold down brackets like you described. I too will be interested in other feedback.

[takepride]

Not sure about the cause, but I've been using NAPA battery terminal cleaner, followed by NAPA Battery Terminal Protector, both sprays. The cleaner foams up around the terminal and really cleans it up good. It seems to cling. It also did a great job of cleaning up my bus bars, isolator, fuses etc. No scrubbing, etc.

It sounds like your batteries are over-gassing and hence the dampness and deposits. Some gassing is normal. I finally went with AGMs and have eliminated the problem. Though certainly not cheap they operate a lot better, last a lot longer and require no maintenance or cleaning. Now the only cleaning I have is road dirt.

[OldForester]

Thanks for your suggestions. I like all of them.

I will look for the NAPA battery terminal cleaner and the associated protector, and use it until it's battery replacement time. Then I will go to AGMs and get rid of the battery fill system. I will be glad to have nothing but the batteries to clean from road dirt and not have to work around all the hoses, and clean around them all the time.