1. Charging IC first detects whether there is an output short-circuit or overload protection mode, such as normal system, and then see whether the battery voltage is 3V, above 3V can directly into the constant current charging, below 3V, then the current with constant current 10% of the pre charging;
2. Constant current fast charging stage: rise to 4.2V;
3. Constant pressure stage: the battery is up to 4.2V, the voltage is no longer elevated, charging current appears decreasing trend until the constant current reaches 10% stop charging.