The process is quite simple. You will need the following items: a flat screwdriver, Philips-style one, a fully charged compatible battery. 1. Unscrew the 4 Phillips bolts holding the front box cover (2 on the left and 2 on the right side of the box). Remove the cover (put the finger next to the handlebar and pull the cover into the seat direction). The battery will show up on the right side. 2. Take off the metal strap holding the power cell (one flat bolt) and unscrew the leads holders (first the negative one, then the positive). Remove the power cell. 3. Install a new battery and fix it with the metal holder. Then hook the leads to the power bank and fix the screws on them. Set all the screws firmly but don’t over tighten them. 4. Put the cover back and secure it with the 4 Phillips screws.