woodchucker wrote:

Generally they are not just connected in series.
Nicads and nimh were, but not lion or lipo.


The better batteries have prongs for the drill, or whatever
and another set for monitoring the cells. Charging can be done on the
normal prongs, but monitoring is done on the second set. They are not
monitoring for heat like nicad and nimh, they are monitoring for
voltage. They need to be close, and they can't exceed the recommended
cells voltage. Same with depletion of batteries, they can't be drawn
down to low or they may not charge again, or worse. So the
manufacturers have handled that. You'll see all the lion/lipo units
stop when voltage drops. So if you are drawing a lot of amps it will
cut out. let it cool and the battery bounces back a bit and you can
continue... but it's a matter of time b4 it stops running and needs
charging.
Even the cheapies have something, probably not as good. Take a look at
your pack, you will see another set of connectors.

I love the Lithium technology the drills are always ready. No quick
discharge like the nicad/nimhs had.


Very good explanation of things I was not aware of - thank you Jeff. I was
well aware of the drop off characteristics of LiON, but did not know the
underlying logic. I too love LiON, and have had no problems at all with
it - either in my laptops or in my drills.

--

-Mike-