Compaq Presario,Presario 1211 Supplementary Manual page 84

If you will not be using your
Notebook for an extended
period of time, Compaq
recommends that you unplug
the electrical cord from the
outlet and remove the
battery while your Notebook
is not in use.
Battery charging time will vary based on the initial battery
charge, the type of battery, and the activity of your Notebook
while charging.
Over time, all batteries lose the ability to operate at full
capacity and the battery will have to be replaced. To purchase
a new battery, contact your Compaq-authorized dealer or
access the Compaq Web site at: www.compaq.com/athome.