Acer Chromebook CB5-312T-K 8Z9 Battery Replacement

First begin by flipping the laptop on its back and having the back cover face you directly.

Then unscrew the ten Phillips head screws that hold down the back cover using a Phillips #0 Screw Driver.  

Using a plastic spudger, open the back cover and remove it from the laptop.

look for the battery in the bottom half of the computer

Once you have found the battery, look for the screws that secure the battery, in the upper left and right corners.

Begin by unscrewing the two Phillips head screws that hold down the battery using a J1 sized screwdriver.

Finally remove the battery from the laptop.