NEC MOBILEPRO 900 - Manual (Page 109)

Troubleshooting A-9
6. Replace the backup battery cover. Tighten the screw to secure the
cover.
Replacing the backup battery cover
A – Screw B – Backup Battery Cover
The battery can explode if you use a battery
that is not the same type battery (or an equivalent type) that ships with
the MobilePro. Use only the same type battery or an equivalent type
when replacing the battery.
Do not recharge or disassemble battery.
Do not dispose of battery by burning it.
Lithium acts as a catalyst when exposed to water and causes
spontaneous combustion on contact. Discard used batteries according
to the manufacturer’s instructions. Promptly dispose of used battery.
Keep battery away from children. If battery is swallowed, see a doctor.