Ted Pillinger wrote:

What is the fastest rate of discharge advisable for a sla battery?

Your best bet would be to look up the specs on this. The figures vary a
fair bit.

Is the terminal voltage a good indication of the condition of a charged
battery?

It's *an* indication, just not a *good* indication.

With a known tested battery, once you have a discharge curve outline, it can
be used to give a reasonably good indication of where the charge level is.

However, and especially if you're going to abuse the battery, as it ages,
the curve shape changes and will no longer give you a good indication (till
you retest again anyway).

If good charge indication is really important in this application, doing
something like what's done nowadays with a dynamically determined level (not
sure if there's any official terminology for this) would be best. It
continually estimates the level going on how much has been taken from the
battery, based on the capacity that was determined last time it was fully
discharged. Or something along those lines.
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