Patent ID: 8372553

Claim:
A fuel cell system comprising: a fuel cell stack including a plurality of fuel cells defined by bipolar plates separated by membrane electrode assemblies; and a cell voltage monitoring sub-system including wires electrically coupled to each bipolar plate, said cell voltage monitoring sub-system further including a plurality of differential amplifiers where a wire coupled to one bipolar plate is electrically coupled to a positive input of one differential amplifier and a negative terminal of another differential amplifier, said cell voltage monitoring sub-system being configured to: determine if a wire connection has failed by measuring the voltage of each fuel cell in the fuel cell stack; determine if the measured cell voltage of one of the fuel cells is below a first predetermined voltage; determine if the measured cell voltage of an adjacent fuel cell to the one fuel cell is above a second predetermined voltage; and determine that a connection to a common bipolar plate between the two fuel cells has failed if the voltage of the one fuel cell is below the first predetermined voltage and the voltage of the adjacent fuel cell is above the second predetermined voltage.