Several times I left discharging the Wistrio Lora 5205 during the night to test the Voltage threshold from which the board stops.
This morning I found the LIPO battery completely discharged (1V) and swolen! That the second time it happens with a different battery and a different board.
Looking inside the hardware, I found a battery charger (BQ21040) that seems to only manage battery charging cycles and a 3.3V regulator (RP104N331), that converts 5V or VBat to 3.3V.
Into the firmware, I looked for some battery power management but I didn’t found any code that will shutdown the module if the main voltage drops below 3,1V (for example). Just some functions measuring the battery level and the board power source to save battery (I imagine). There is some callbacks defined but never used for this purpose.
Can someone explain what mechanisms are used to manage the battery voltage and, if it’s not present, how can we implement it (hard or soft), especially how to completely shutdown the board by software to save battery life?