1. Turn your Sony PCG-71311L laptop over.
2. Find the laptop battery release button lock for your Sony PCG-71311L laptop.
3. Now that your Sony PCG-71311L laptop battery is unlocked, find the battery release button down.
4. Holding the laptop battery release button, gently pull your battery away from the laptop.
5. Now that your Sony PCG-71311L battery is removed, grab your replacement Sony PCG-71311L battery for installation.
6. Insert the battery into the slot. Push the Sony PCG-71311L battery towards the laptop and secure it in place.