iPhone Battery Adhesive Removal

I really wouldn't recommend putting acetone in your phone. The best route is heat & pry. Anything is good, just don't get the phone too hot. If it's too hot to touch you've gone too far. But you can use a hairdryer, iOpener, heat gun, or even hold the phone near a hot (electric) stove. But don't try to dissolve the strips.

If you pry up at the edges of the battery (after heating) carefully you should be able to reach the adhesive strips again, and pull them out. I was replacing the battery on a 5s once and this is how I got it to work.

I hope this answers your question.