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wrote:
I just got a cordless drill (12v Hitachi) for the first time. Can the
battery be left in the charger continuously (like a cordless phone) so
that it's fully charged at all times or would this damage the battery
or charger? The only thing I know about the battery/charger is that
it's a Ni-Cad battery and the charger has an indicator light that turns
off once the battery is charged.

Thanks.

Charles Lerner

Don't know about the Hitachi charger, but it is best to
treat them all as suspect. They may say they will turn off
or only allow a trickle, but you can never tell. First step
is to find out what the charger information says. Second
step is to find out the time for a full charge, then never
charge for longer, and disconnect after the charge. I have
a friend who charges only when he needs the drill.
Personally, I charge from time to time based on what a full
charge time is and the volt reading; i.e. if a full charge
is 5 hours, then I charge for maybe 3 hours if the voltage
is below 12.5 volts, a full charge (allowing time for the
battery to settle down) is about 13.1 to 13.2 volts. For a
12 volt pack you will have 10 cells. Whatever you do, do
not let the pack get below 10 volts (1 volt per cell) and
never always be wary of overcharging.