If any of the adhesive strips broke off and the battery remains stuck to the rear case, remove it by adding a few drops of isopropyl alcohol (90% or greater) underneath the battery near the stuck strip(s).

After about a minute, gently lift the battery.

Do not insert your spudger in the area between the volume down (-) button and the top edge of the battery, or you may damage the volume control cable lying underneath.

Do not pry against the logic board or you may damage the phone.

Don't try to forcefully lever the battery out. If needed, apply a few more drops of alcohol to further weaken the adhesive. Never deform or puncture the battery with your pry tool.

If the battery remains stuck to the rear case, prepare an iOpener or use a hair dryer to heat the rear case directly behind the battery. It should be slightly too warm to touch comfortably.

Overheating the iPhone may ignite the battery.

A piece of dental floss may be used to separate the battery from the rear case. A stronger alternative to dental floss is an unwound guitar string, such as a 0.009 E string from a 12-string set. Thread the floss or string behind the upper battery corners, bring the ends together, wrap them around a folded cloth, and pull evenly.