Battery Packs; Running The Notebook On Battery Power - Compaq Presario R3000 - Notebook PC Hardware Manual

Running the Notebook on Battery
Power
The notebook switches between AC power and battery power
according to the availability of an external AC power source,
always preferring AC power. If the notebook contains a charged
battery pack and is running on external AC power, the notebook
will switch to battery power only if the AC adapter is
disconnected from the notebook.
Keeping a battery pack in the notebook enables the battery pack
to charge whenever the notebook is connected to external power
and also protects your work in case of a power outage.
On the other hand, a battery pack in the notebook slowly
discharges even when the notebook is powered off. Whether to
leave a battery pack in the notebook or in storage depends on how
you work.
Hardware Guide

Battery Packs

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