A nicad is charged at 1.35v, its dead at 1.2v, listening to the idiot
that says run them dead will kill them or reverse their polarity and
ruin them. Nicads are meant to be stored at 1.2v or discharged, they are
not Lead Acid type , do not sulfate. Leaving them on the charger is bad.
But your drill company does not tell you this since their real profit is
giving you a drill, and seling you replacemeny packs.