HP EliteDesk 800 G1 Maintenance & Service Manual page 50

Type 2
a.
Push the battery toward the outside of the chassis to release it from the holder and lift it out.
b. Lower the battery so that is next to the holder then push it into the holder.
NOTE:
5. Replace the computer access panel.
6. Plug in the computer and turn on power to the computer.
7. Reset the date and time, your passwords, and any special system setups using Computer Setup.
8. Lock any security devices that were disengaged when the computer access panel was removed.
42 Chapter 5 Removal and Replacement Procedures
After the battery has been replaced, use the following steps to complete this procedure.