Reason:

　　1. The indicator light of the charger may be damaged. At this time, there will always be a green light or no light. You can find a professional to repair or replace the indicator light.

　　2. If the battery is damaged, you can find a professional maintenance point for maintenance, or you can directly replace it with a new one.

　　3. It is also possible that the battery is aging or the battery is charged with virtual electricity, causing the charger to display green light but the electricity is not fully charged. It is recommended to activate the battery before charging. If the battery still doesn't work, it's not the battery, but the charger itself and the wiring.

　　4. From the charger's point of view, the filter resistor or filter capacitor in the charger may be damaged, or it may cause the charger to display green light but not fully charged. At this time, you need to replace the charger directly. If it is not serious, you can also find someone to repair it.