🚀 go-pugleaf

Be absolutely sure that rechargeable batteries are NiCad before trying
to discharge them completely.  Nicads sometimes need this done several
times to cure the "memory effect" of partial discharge, but running
the pack down too far can be *fatal* to the sealed lead-acid batteries
that are also being used more frequently these days.  If the specs
don't say, you can distinguish these 2 types by measuring the
individual cell voltage or dividing the nominal battery voltage by the
number of cells.  Nicad is about 1.25V, while lead-acid is about 2V
per cell.

Also, over-discharging Nicads can cause them to develop cell reversal
and/or internal shorts.  As a rule of thumb, the best thing to do is
to operate the device until it stops running, then immediately
recharge the battery.