If the temperature difference between 2 sensors is >1.5°C, cooling is activated. Test interval 5 min. The battery voltages are monitored.
Li-Ion 3.7V battery direct connected to D1mini (ESPEasy) pin 3V3. deepsleep 15 min. voltage measure with 100k between 3V3 and A0. display value calculation = %value%/1024*4.1