1. First, fasten the plastic baffle in the concave hole, as shown in the figure below.
2. Then unplug the battery in the opposite direction, as shown in the figure below.
3. After that, the battery falls off, as shown in the figure below.
4. Take a new battery and put it in the battery box again, as shown in the figure below.
5. Install the plastic baffle of the battery as shown in the figure below.
6. The number on the display screen indicates that the battery has been successfully replaced, as shown in the figure below.