1. Turn your HP tx2645ei laptop over.
2. Find the laptop battery release button lock for your HP tx2645ei laptop.
3. Now that your HP tx2645ei 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 HP tx2645ei battery is removed, grab your replacement HP tx2645ei battery for installation.
6. Insert the battery into the slot. Push the HP tx2645ei battery towards the laptop and secure it in place.