Twist the opening pick to fully dislodge the battery and remove it.

Remove any remaining adhesive from the phone, and clean the glued areas with isopropyl alcohol and a lint-free cloth.

Lay the replacement battery in place, but do not apply adhesive yet. Resume re-assembly until the motherboard is in place (STEP 18).

Apply new pre-cut adhesive or double-sided tape onto the phone frame, around the perimeter of the battery compartment, but not in the rectangular cutout in the center (which is actually the back side of the display).

Temporarily connect the battery connector to the motherboard to ensure proper battery alignment.

Press the battery firmly into place for 5-10 seconds. Disconnect the battery and resume re-assembly.