The battery needs to be replaced after approximately 3 years if you use it every day. When used only once a week, you won’t need to replace the batteries for some 7 years. If you don’t charge WakaWaka for a whole year, the capacity of the battery will be damaged. You can lose approximately 20% battery capacity. So make sure you keep using it!
We don’t have a program to change your battery yet, since we want to develop a program that works on-grid and off-grid.