Keep The Top Of Flooded Batteries Bone Dry

MEXICOWANDERER wrote:
Cell to cell electrical leakage can and does develop if the top of the battery gets wet. This is an issue with flat top recessed cap batteries. The leakage can grow and become dozens of milliamps. It is especially wonderful if leakage is cell to cell causing the state of charge balance to become unequal.

Smear dialectric silicone grease on filler cap plugs to seal. The built in cap vent acts like a minor league recombinant chamber.

And remember MOST of the unexplainable corrosion of battery terminals comes from the imperfect seal between the battery lid and lead battery post. The temperature expansion rates are wildly different and the culprit is GAS not liquid electrolyte.

When I bought this MH 10 years ago I was worried of my Magnatech converter "boiling my batteries dry so I was always overfilling the cells causing the wet top as you describe and a lot of corrosion. This coupled with heavy inverter and alternator usage caused a lot of corrosion at the terminals and angle iron to hold the batteries in place. The corrosion was green and a wet build up. The corrosion actually ate some of the terminals away. I now fill the cells to about a 1/2 in from the top, run my refer on propane and clean the tops of the batteries when I fill with water. This has greatly reduced corrosion. However I still get corrosion on my angle iron to hold down the batteries.