A flex circuit and a battery module including the flex circuit are provided. The flex circuit includes a first plurality of conductive traces and a second plurality of conductive traces. Each of the first plurality of conductive traces includes a first terminal configured to be electrically coupled to a first location of a respective one of a plurality of busbars that electrically connect battery cells of the battery module, and a second terminal configured to be electrically coupled to processing circuitry. Each of the second plurality of conductive traces includes a first terminal configured to be electrically coupled to a second location of a respective one of the plurality of busbars, and a second terminal configured to be electrically coupled to the processing circuitry. The processing circuitry is configured to measure a voltage level of each of the plurality of busbars using the first and second plurality of conductive traces.