1. Turn your Toshiba L550-145 laptop over.
2. Find the laptop battery release button lock for your Toshiba L550-145 laptop.
3. Now that your Toshiba L550-145 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 Toshiba L550-145 battery is removed, grab your replacement Toshiba L550-145 battery for installation.
6. Insert the battery into the slot. Push the Toshiba L550-145 battery towards the laptop and secure it in place.