I'm getting a lot of corrosion on one of my two 6V batteries, enough that I've had to replace the terminal nuts twice in the last year or so.Since I bought my Fleetwood Storm a little over three years ago, I've kept the batteries topped off with distilled water. They occasionally appear like they're low on water, but the level has never gotten so low that the plates are exposed. When I park it in storage, I hit the disconnect switch so they don't run down, and I only plug into shore power when at campgrounds with 30A hookups or when parked in my driveway (15A) when getting ready for a trip, probably 10-20 days a year.Some more background: Last time I checked, the battery with corrosion read about 0.05 volts less than the other battery on my voltmeter, and my cheap hydrometer gave a slightly lower reading on one of the three cells. Also, I'm my Storm's power converter is a WFCO 55-amp model WF-9855.What could be causing all this corrosion?

Battery boiling from overcharging.

Parasitic draw(s) followed up by excessive charging

OldBlackWater wrote:I'm getting a lot of corrosion on one of my two 6V batteries, enough that I've had to replace the terminal nuts twice in the last year or so.Since I bought my Fleetwood Storm a little over three years ago, I've kept the batteries topped off with distilled water. They occasionally appear like they're low on water, but the level has never gotten so low that the plates are exposed. When I park it in storage, I hit the disconnect switch so they don't run down, and I only plug into shore power when at campgrounds with 30A hookups or when parked in my driveway (15A) when getting ready for a trip, probably 10-20 days a year.Some more background: Last time I checked, the battery with corrosion read about 0.05 volts less than the other battery on my voltmeter, and my cheap hydrometer gave a slightly lower reading on one of the three cells. Also, I'm my Storm's power converter is a WFCO 55-amp model WF-9855.What could be causing all this corrosion?Too much water causes them to gassify and boil out acid. Use new nuts and then installed apply a liberal coverage of plain old VASOLINE and they wont get cruddy after you do. Keep water at the proper level.

You need to diagnose whether this is a battery with a bad cell. That is where to start.Use a hydrometer to recheck both batteries. With batteries fully charged and charger turned off, check SG. If OK (no bad cells) then the next thing to check is the voltage your converter or charger is putting out. Some are adjustable, some are not.If the charger is not adjustable in terms of output voltage, an inexpensive alternative while in storage and plugged into shore power is to by a HD 120 VAC timer (20 amp) from any box store. Plug your converter into it and let it run for 20 minutes a day. That should certainly keep up with the self discharge rate.

Put one or two pennies close to each battery post & they will keep the posts clean.They will soak it all up.Yes really!!Could get kind of pricy tho,could use up 5 or six pennies a year.

Excessive battery corrosion | Good Sam Community

tratterboy1
Explorer
Jun 04, 2015
Put one or two pennies close to each battery post & they will keep the posts clean.They will soak it all up.Yes really!!Could get kind of pricy tho,could use up 5 or six pennies a year.
wolfe10
Explorer
Jun 03, 2015
You need to diagnose whether this is a battery with a bad cell. That is where to start.

Use a hydrometer to recheck both batteries. With batteries fully charged and charger turned off, check SG. If OK (no bad cells) then the next thing to check is the voltage your converter or charger is putting out. Some are adjustable, some are not.

If the charger is not adjustable in terms of output voltage, an inexpensive alternative while in storage and plugged into shore power is to by a HD 120 VAC timer (20 amp) from any box store. Plug your converter into it and let it run for 20 minutes a day. That should certainly keep up with the self discharge rate.
Sully2
Explorer
Jun 03, 2015
OldBlackWater wrote:
I'm getting a lot of corrosion on one of my two 6V batteries, enough that I've had to replace the terminal nuts twice in the last year or so.

Since I bought my Fleetwood Storm a little over three years ago, I've kept the batteries topped off with distilled water. They occasionally appear like they're low on water, but the level has never gotten so low that the plates are exposed. When I park it in storage, I hit the disconnect switch so they don't run down, and I only plug into shore power when at campgrounds with 30A hookups or when parked in my driveway (15A) when getting ready for a trip, probably 10-20 days a year.

Some more background: Last time I checked, the battery with corrosion read about 0.05 volts less than the other battery on my voltmeter, and my cheap hydrometer gave a slightly lower reading on one of the three cells. Also, I'm my Storm's power converter is a WFCO 55-amp model WF-9855.

What could be causing all this corrosion?

Too much water causes them to gassify and boil out acid. Use new nuts and then installed apply a liberal coverage of plain old VASOLINE and they wont get cruddy after you do.

Keep water at the proper level.
Old-Biscuit
Explorer III
Jun 03, 2015
Parasitic draw(s) followed up by excessive charging
2oldman
Explorer II
Jun 03, 2015
Battery boiling from overcharging.

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