In article ,
newshound writes:
On 13/05/2014 08:32, Adrian wrote:
On Tue, 13 May 2014 04:54:43 +0100, Bill Wright wrote:

Given two 12V lead acid gell batteries, both new, both the same type,
but from different sources, how do I balance the charge before fitting
them in a 24V appliance?

Chuck 'em both on the same 12v smart charger until they reach "float"?

But not at the same time.

For float (up to 13.8V), they will be fine together in parallel,
as you can leave lead acid batteries on that forever. (Ideal float
voltage varies a bit with the precise battery type.)

For cyclic charge (= 14V), then charging together is not so good
as one may be gassing for a while as the other is still charging.
As a one-off, it probably won't matter, but you wouldn't want to
do it regularly. It is done (in both series and parallel) where
they are identical, same age, and replaced together at end-of-life,
but then the life you get is that of the shortest lived.

--
Andrew Gabriel
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