Removing the Coin-Cell Battery:
Follow the procedures in Before Working Inside Your Computer .
Remove the:
VESA stand
back cover
system-board shield
Press the release latch away from the battery. The battery pops-out from the socket; lift the coin-cell battery out of the computer.
Installing the Coin-Cell Battery:
Place the coin-cell battery into its slot on the system board.
Press the coin-cell battery downward until the release latch springs back into place and secures it.
Install:
system-board shield
base cover
VESA stand