Before starting, make sure your device is completely powered off and unplugged. Use the proper tools if needed (usually included in the package). Do not force anything—if you're unsure, seek help from a professional.
This tutorial will guide you in detail how to replace the Apple A1175 / MacBook Pro 15" A1150 A1226 A1260 battery.
Step 1
Use your fingers to push the two battery release latches away from the battery, and then lift the battery out of the MacBook.