NEC 750C - Manual (Page 23)

2-10 Getting Familiar with Your MobilePro 750C
T
If you use the MobilePro without the back-up battery in-
stalled, MobilePro memory may be unstable. The con-
tents of MobilePro memory may be lost if the main
battery is removed.
T Always back up your data onto your notebook or desk-
top computer before replacing the back-up battery.
Main Battery
Should you notice the life of a charged battery pack is short,
replace it with a new one. Follow these instructions below
to replace a battery pack.
1. Save your data, turn off unit power, and close the dis-
play panel. Disconnect any cables attached to the unit,
such as the AC adapter cable.
NOTE
If you receive messages indicating that both
the main battery and the sub-battery (back-up bat-
tery) are very low, replace the back-up battery first.
If a drained main battery is not replaced, the back-
up battery drains more quickly than normal.
2. Have a new Lithium-Ion battery pack available.
3. Slide the battery cover lock to the unlocked position.
4. Slide the main battery bay cover toward the arrow and
remove the cover.