For this step, insert a plastic card into the edge with a wider gap between the midframe and the battery so that you have more space for the plastic card and get a better leverage.

Carefully slide it underneath the battery to loosen the adhesive.

Slide the plastic card underneath and pry up the battery from its recess.

The battery should come off easily. In case the battery is still sticky, repeat the previous adhesive remover procedure or use an iOpener to further soften the battery adhesive.