Compaq 1610 Reference Manual page 42

5. Remove the compartment cover and old battery.
Wipe the surface of the new backup battery with a soft cloth,
6.
then place it in the backup battery compartment with the
positive (+) side facing up.
Replace the compartment cover and tighten the screw.
7.
Turn over the handheld PC, open it, and press the power
8.
button to resume operation.