When the universal charge is working normally, the input voltage is 220V AC, and the output is 4.2 ~ 4.3V DC. Rechargeable battery voltage is about 3.7V. Charge according to the voltage difference between the universal charge output voltage and the rechargeable battery.
Rechargeable battery in the charging process with the increase of battery power, the voltage will slowly rise, when the rechargeable battery voltage close to the universal charge output voltage charging current gradually reduced to 0. When the voltage of the rechargeable battery is equal to the output voltage of the universal charge, the charging stops.
The intelligent universal charge limits the charging current and avoids the damage of excessive charging current to the rechargeable battery.
The intelligent universal charge also has the automatic stop function after charging. When the battery voltage reaches a certain value, the universal charge automatically stops charging, which protects the battery and avoids the danger of explosion caused by overcharging the battery.