Do I need to 'work up' batteries after a rest?

[frackers]

The mill was down for three months (first quarter of the year) due to damage but I kept the battery bank (8 off series/parallel 225Ahr golf cart batteries for 24v) topped up using a charger. No appreciable discharge occurred during this time.

Now I'm finding with even light winds the bank voltage rises quite quickly at relatively low charge rates (10amps sees over 28volts) and that discharging at my normal 40 amps (1kw dump load) is dragging the volts down to below 23volts within a few minutes.

Would people here recommend 'working up' the battery bank with a few discharges to say 80% full and using a charger to get back to full charge quickly (we don't have much wind at present) or is this an indication of real battery problems. They are coming up to 3 years old and never discharged below 80% apart from a couple of times during earthquake recovery last September when I took them down to 50%. I've not got a hydrometer at present (last one got broken) but I think I may invest in a new one to check things out...

[wpowokal]

Short answer yes, because lead acid batteries left on trickle charge will sulfate (become couch potatoes) they, like us need exercise.

Long answer, all wet lead acid batteries will benefit from a deep discharge (yes I know it takes some life off but so does sitting) dischage them until the first 2V cell reaches 1.85V then recharge, this is something one might do every few years. And no you won't read that in manufaturers instructions.

Allan