Can a 5.2V charger directly charge a 3.7V lithium battery?

It depends on how you charge it. It definitely won't work if you charge the battery directly. The maximum charging voltage of lithium battery is 4.2 volts (generally, the working process of lithium battery charger is to use cross current to charge. The battery will approach 4.2 volts at the beginning of charging, then use constant voltage charging When the charging current is less than 100mA, charging ends at 5.9 volts But if you put the battery on the phone and then use this power source. power supply to power the charging port of the phone, everything should be fine Take a look at the original direct charge charger from Nokia, the voltage is 5.7 volts Finally, to summarize, this power supply can power the battery. , but it cannot charge the battery directly. It can be used as a direct charger to charge the battery.u cell phone, or you can create a charging circuit. Finally, I would like to ask: do you have a direct charger, the type that can be plugged into your cell phone's charging port? If so, as long as the interface is correct and the positive and negative poles are correct, all mobile phones can be used. Be professional, don't joke if you don't have electrical knowledge, there is a risk of explosion if the lithium battery is not well charged.