It wasn't mentioned if the charger was powered on or not, here is some information concerning both situations.
The manual has the following note:
To preserve a battery's charge, don't leave it in the recharger if the
power adapter is not plugged into an electrical outlet.
Leaving a battery in an unpowered recharger would drain the battery. Leaving it in an unpowered charger for an extended period of time could discharge the battery to a point where damage to the battery could occur.
Leaving a battery in a powered charger for extended periods of time╩will not be a problem. There are three steps in the charging process.
First a bulk charge is done if the battery voltage is below a certain level. After the bulk charge, the voltage applied to the battery is reduced to finish the recharging process. The charger then switches over to a trickle mode which is used to maintain the full charge to the battery.
Do not leave the power adapter in the PowerBook if it is not plugged into an electrical outlet.
Leaving a battery in the PowerBook with the power adaptor plugged into the electrical outlet for extended periods of time will not be a problem.
Article Change History:
25 Apr 1995 - More information added on leaving the PowerBook plugged in.
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