Compaq Armada M300 Series Reference Manual page 46

4. Push the battery pack onto the computer until the contacts
connect , and rotate the battery pack 90 degrees toward the
back of the computer
5. Slide the two battery latches out (away from each other)
If the computer will be unused and unplugged from an external
power source for more than two weeks, remove and store the
battery pack(s).
Proper storage procedures reduce the self-discharge rate of a
battery pack. Store a battery pack in a cool, dry place within the
following temperature ranges.
.
.