Place a spudger into the small gap between the plastic frame and the battery, opposite the display cable.

Carefully pry the battery up and out of its recess.

The battery is adhered to the core with mild adhesive. If it feels stuck, lightly heat it with an iOpener or hair dryer to soften the adhesive underneath.

Don't try to fully remove the battery just yet, as its connector is still adhered to the core assembly.