Maybe the charger technology from the bosch pro-tools has made it to
the diy stuff. The pro charger/batteries are first class. I have a
14.4V drill and 14.4V impact driver - they can both be worked hard day
after day. I leave the not-in-use battery on the charger all the time
(only swapping cells as one begins to slow) - which is meant to be ok
nowadays.