I have a arduino pro micro 5V that I want to power with a 3.7V lipo. I also have a charging module to charge the lipo. (https://www.banggood.com/nl/TP4056-1A-Lipo-Battery-Charging-Board-Charger-Module-Mini-USB-Interface-p-1027027.html?rmmds=myorder&cur_warehouse=CN).
I want to measure the battery level of the lipo.
How can I measure it? I read that you can't just use analogRead because the lipo itself is the reference.
Thanks in advance!