Unusual Loss of Battery Electrolyte

[gepaine]

I have two 12-volt batteries that I removed from my trailer, topped off the electrolyte, and put on a trickle charger in my garage around mid-October. They are about 2 1/2 years old. I checked the charge level and electrolyte level around Dec 1st. The charge level was 13.25 volts (when disconnected from the charger), and 9 of the 12 cells showed essentially no electrolyte usage. However, 3 cells on one battery (call them #4, #5, and #6 counting from the left) had used about 1/8 inch of electrolyte. (It was still well above the top of the plates.)

I topped off the electrolyte in the 3 low cells and reconnected the charger. Today (about 5 weeks later) I checked the charge level and electrolyte level again. Charge was still 13.25 volts, and once again the same 3 cells were about 1/8 inch low.

Last winter I left the batteries on the charger while we went south for 3 months, and when we got back, all of the cells were down just a little - maybe 1/16 of an inch. This year, I think the 3 cells are losing electrolyte too fast to leave on the charger while we are out-of-town.

Has anyone seen this type of uneven electrolyte usage? Does anyone know what this says about the condition of the battery?

Thanks

[JRTJH]

Possibly a cap problem???? If the batteries are identical, move the cap from the "good" battery to the one losing electrolyte and put the "bad" one on the known good battery. See if the problem moves with the cap......

[gepaine]

I'll follow your suggestion, but I doubt it is the cap. It seems to be in good shape and should provide a good seal. Plus, from what I've read about loss from evaporation, it doesn't seem I would lose that much in such a short time. I'll post the results of this test when I return from our snowbirding trip.