How to Measure 3.7V Battery Level on Arduino Using Voltage Divider and ADC

Hello everyone,

I have an Arduino powered through a DC-DC converter to 5v from a battery 3.7v .

I need to know how can I measure the battery level or the remaining capacity in the battery as we see in any smartphone or laptop, I read that I can do it through a voltage divider but what's the next step ?



Thanks in advance,

Just connect the positive pole of the battery to an analog input of your µC. Now you can read the voltage of the battery with your controller.

Battery level and battery capacity are two totally different things. Your voltage divider (with noise suppression) and an ADC input on your uC will solve the first, the second is more complex, and often involves a "fuel gauge chip", or an algorithm running on your uC, the output based on some typical discharge behavior.
DC-DC converters are constant power systems, as the input voltage drops, the input current increases, equivalent to a negative resistance, which complicates determining remaining capacity, since you don't have a constant load resistance.
Cheers,
Richard