Charging A Battery Pack - HP Compaq Series Hardware Manual

Battery Packs

Charging a Battery Pack

All battery packs inserted into the notebook charge whenever the
notebook is connected to external power through an AC adapter
or an optional Automobile Power Adapter/Charger.
An optional Aircraft Power Adapter can be used to run the
notebook, but it cannot be used to charge a battery pack.
A battery pack can charge whether the notebook is off or in use,
but it will charge faster when the notebook is off. Charging might
be delayed if a battery pack is new, has not been used for 2 weeks
or more, or is much warmer or cooler than room temperature.
When a battery pack is charging, the battery light on the notebook
is on. The light turns off when all battery packs in the system are
fully charged.
Hardware Guide 3–6