You did not say whether this battery is for an electric trolling motor,
or for a electrical system on a larger powered boat system? An
electrical trolling motor experiences high discharge, and gets hot,
resulting in condensation as it cools down. As it is used, it also
boils out the electrolyte, which is why you cannot use the battery in a
completely sealed compartment, and though the battery is described as
sealed, it is vented as well. What condenses typically is the recently
boiled out electrolyte, which then gets concentrated in the battery
compartment bilge.

If you are getting a large splatter area, try a trickle charger. It
sounds like you are overcharging the battery if they are only lasting a
couple of years, especially on a boat if it is not used continually.
Does the boat have its own charging system? Are the batteries put away
discharged? Or are you charging to just keep them topped off, ready for
the next outing? Overcharging just boils them dry, and kills them
quickly! TnT

Life is about each moment of breath,
Living, about each breathless moment!

Thanks, KnesisKnosis, aka Tinkerntom, aka TnT

and now a friendlier, "RkyMtnHootOwl"


2 WW kayaks,
'73 Folbot Super,
pre '60 AEII
77 Hobie Cat 16


DSK wrote:
says...

I have two "maintenance free" sealed batteries. Yesterday when I
checked the battery trays where the batteries are secured in place, I
found that both battery trays are quite wet (like 1/16" deep). This is
odd. The batteries are inside a compartment that is protected from
elements, and the rest of the compartment is completely dry -- only the
battery trays are wet. I am sure the water is not from the air because
the air in early winter is relatively dry.


Hmm, seems likely that it is condensed battery electrolyte. They are
hooked up to a charger, yes?

jps wrote:
Moisture condensation from heating a cooling of the battery during
charge cycles?


Possible

Did you test to see whether the liquid was electrolyte? I little
splashed on your best jeans will tell you within a couple of hours.


A better test is to drop a pinch of baking soda in it.

BTW you should mix up a solution of baking soda in distilled water and
use it to wipe down the area around your batteries. You'd be amazed at
what that stuff gets on, and it is very corrosive.

Fair Skies
Doug King