Toshiba Pockey PC e800 User Manual page 27

Basic Skills
3. Attach/Detach the battery from the Pocket PC
You cannot turn on the power if the Battery Pack Lock is in the Release
Position.
You can change the main battery without data loss because the Toshiba
Pocket PC e800 has a rechargeable backup battery. However, the capacity
of the backup battery is limited, therefore when you change the main
battery, attach the new main battery and switch the Battery Pack Lock to
the lock side as soon as possible.
User's Manual 2-9