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 remove the Apple A1309 / MacBook Pro 17" Unibody A1297 (Early 2009-Mid 2010) battery.
Step 1
Remove the screws
Remove the screws with a screwdriver and remove the back cover.
Tips: Shut down and close your MacBook. Lay it on a soft surface top-side down.
Step 2
Unplug the battery connector
Slowly and gently unplug the battery connector near the logic board.
Step 3
Remove the battery
Use a screwdriver to remove the three screws securing the battery and remove the battery.
Step 4
Install the new battery
Install the new battery, tighten the screws, connect the connector, and finally put on the back cover.
NOTE: If you notice any unusual problems after installing your new battery, you may need to reset your MacBook's SMC.