After 2-3 minutes, slide one corner of a plastic card underneath the battery cell.

This should require minimal force. If you have trouble, apply more adhesive remover along the other edges of the battery cell and give it 2-3 additional minutes to penetrate.

Try not to deform the battery. A damaged or punctured battery can leak dangerous chemicals and/or catch fire.

It may help to gently twist the card to open up a slight gap between the battery cell and the MacBook's case.

Slide the card farther underneath the battery cell to separate it from the adhesive securing it to the case.