Can 18650 batteries charge mobile phones?

The voltage of the 18650 battery is basically the same as that of the mobile phone battery, so the 18650 battery can be used to charge the mobile phone battery.

18650 battery voltage: Common 18650 batteries are divided into lithium-ion batteries and lithium iron phosphate batteries. The voltage of lithium ion battery is 3.6V and 4.2V, the voltage of lithium iron phosphate battery is 3.2V, the capacity is usually 1200mAh-3000mAh, and the common capacity is 2200mAh-3600mAh.

Mobile phone voltage:

The standard discharge voltage is 3.7V, the charge cut-off voltage is 4.2V, and the discharge cut-off voltage is 2.75V. The unit of power is Wh (watt-hour), because the standard discharge voltage of mobile phone batteries is uniformly 3.7V, so it can also be replaced by mAh (milliampere-hour). The conversion relationship between these two types of units on the mobile phone battery is: Watt-hour = Ah × 3.7.