A battery cell monitoring system and method of operating the battery cell monitoring system are provided. The system includes a sense line. A plurality of cell sense units each include a tank circuit having a center frequency and are electrically connected to the sense line. A cell sense reader unit electrically couples to the sense line and includes a variable frequency radio frequency generator for outputting a radio frequency signal having a signal frequency that is variable to the plurality of cell sense units. The cell sense reader unit measures an impedance of the sense line as the signal frequency varies and determines the center frequency of each of the cell sense units. The cell sense reader unit is also configured to determine a cell voltage of each battery cell electrically connected to one of the plurality of cell sense units based on the center frequency determined.