1. Turn your Sony VPCY-115FX laptop over.
2. Find the laptop battery release button lock for your Sony VPCY-115FX laptop.
3. Now that your Sony VPCY-115FX 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 VPCY-115FX battery is removed, grab your replacement Sony VPCY-115FX battery for installation.
6. Insert the battery into the slot. Push the Sony VPCY-115FX battery towards the laptop and secure it in place.