My sense is that the battery's capacity will be severely impaired. You may
have the voltage, but the ampere hours won't be the same. A pint per cell
.... the poor thing was dry!

Trickle Chargers do just that ... constant low rate. But doing that to a
fully charged battery warms the cells and evaporates electrolyte. Monthly
service is probably about right.

A better solution is a battery 'tender' or 'maintainer' that totally cuts
off the charge current based on battery voltage. Kits for these are
advertised in QST.


"Percival P. Cassidy" wrote in message
...
I have a 115AH deep-cycle battery that I bought as a stand-by battery for
my amateur radio station. It has been in a "battery box" on trickle-charge
(using a charger with a "deep-cycle" setting) for most of the time since I
bought it over a year ago, and it has been called on to supply power only a
few times.

Recently I noticed that the "fully charged" LED on the charger was not on
and started investigating further.

Having not encountered any batteries in the last few decades that have not
been sealed and "maintenance free," I was surprised to find tiny print
about checking the electrolyte level every 30 days -- but even then it
took me a few minutes to figure out how to get access to the cells to
check this.

Anyway, when I removed the cunningly disguised covers, I found that the
cells looked totally dry, and each took close to a pint of distilled water
to bring the electrolyte level above the plates.

The battery has now been on charge for about 20 hours at the charger's 12A
setting, but most of the time the ammeter on the charger has shown only
about 5A. The cells are all still gassing.

Is this battery likely to come back to life again, or is it toast? Any
remedial actions to take?

Perce
(This is my usenet alias. I *am* an FCC-licensed "ham," but my real name
and callsign have no relevance to this question.)