On Thu, 22 Feb 2018 18:48:56 -0800, pyotr filipivich
wrote:

Speaking of batteries

How does one go about testing to see if a second hand set of Ryobi
18v batteries are still "good"?
These are the green ones, I am not sure right now what type they
are (Lithium Ion, Ni-Cad, Auto-Cad, Alkaline, or Iron-Pyrite) but I am
not sure if they need replacing or not. I got them, and the charger,
and three tools at a thrift shop. "Guarenanteed not to rip, rot, rust
bust or throw dust - thirty feet or thirty seconds provided the
customer does not fool with them." {"Did you charge the batteries?"
Of course I charged the batteries!
"I told you not to fool with them!"

(OTOH, could be that I was over expecting how much use I could get
of a pair in the circ-saw cutting oak pallets.)

But anyway, testing procedures for batteries?

Or just bite the wax tadpole and get replacements?

Depending on your electrical competence, it may not be all that easy
to test. What you need to do is somehow measure the current from the
battery as you run it flat, from fully charged. Multiply the current
times the time and you get the capacity. It should be somewhere close
(at least 70-80%) of the advertised capacity. The problem is
measuring the current.