If you use four 3.7V or 4.2V lithium batteries (in series) to power a 12V 15W PTC heater, how long can it take... Is the power at the beginning of heating different from the back, so how long can it be used?
This depends on how large the capacity of the battery you use and how much current the heater is, such as a battery with a capacity of 2 amps, then it can only be used for one hour when the discharge current is 2 amps, and two hours when the discharge current is 1 amp. The power that starts heating is high, and the power gradually decreases as the battery discharge time increases.
