An industrial cellular modem includes a radio module powered by a battery, a battery voltage sensor, a transmitted power meter, and a temperature sensor, and a processor having a memory for executing program instructions for a method of dynamic low battery voltage threshold (LBVT) control. A current battery voltage is compared to a current LBVT (CLBVT), and the modem is turned on and a cellular data session begun with a host server if the current voltage is ≥ the CLBVT, or if the current battery voltage is