On Wed, 29 Jun 2005 09:01:04 +0100, "Dave Plowman (News)"
wrote:

In article O2qwe.5961$Iv6.659@trnddc03,
James Sweet wrote:
No, SLA's have completely different requirements, the good news is that
they're much easier to feed properly, a 12v wall wart will usually do the
trick.

But you have to make sure they can't overcharge, as they can't gas safely
like a wet type.

The convention is a 13.8v constant voltage charge.

Right I use a 13.4v/1amp wall wart currently.
Problem is overcharging.
The smart chargers they make for sla's work much like the pulse
chargers for denser battery types. start with a pulse peak rate and
ramp down during the charge cycle. The better ones will also adjust
the charge to form the cells on a weak or sulfated battery and run
rapid discharge cycles to increase battery life...
Problem is they cost so darn much.(My local supplier's SLA chargers
start at 79 bucks and go up.)
Using the walwart I'm lucky to get 100 cycles out of a battery rated
for as much as 250.(United Battery or Powersonic.)