The adhesive strips underneath the battery can rip very easily. Make sure you pull at the tabs in a slow and steady motion and in a flat angle. To prevent the adhesive strip from ripping, it's helpful to twist it around the tweezers.

In case one of the adhesive strips rips and it‘s not possible to pull it out completely, you can use isopropyl alcohol or an heated iOpener to loosen the adhesive. After the adhesive is soft enough use a prying tool such as an opening pick or a plastic card to pry out the battery.