Use a Phillips #000 to remove three 3.0 mm screws holding the battery and it's housing.

Remove the battery housing with the battery from the main board and set it aside.

At this point the battery is still attached to the motherboard by a connector so don't pull it off the board.

If you're not replacing the battery, you can leave it attached to the board to complete the repair, just be careful when moving them so you don't damage the connection.