A device for measuring cell voltages in a fuel cell having N electrochemical cells separated by bipolar plates, where N is a natural number, the device comprising: - at least two voltage measurement modules (1,2), each module being capable of measuring M voltages on a set of contiguous cells of the fuel cell, where M is a natural number less than or equal to N/2, the group of cells measured by the first module being adjacent the group of cells measured by the second module, - an electronic computer, and - a wired communication bus connecting the at least two measuring devices to the computer in series, each of the measurement modules comprising: - mechanical means for attaching the module to the fuel cell, - electronic means of voltage measurement, - electrical means for connecting the bipolar plates to at least one electronic voltage measuring means, - means for connecting the electronic voltage measurement means to the communication bus, and each module being shaped to cooperate with the adjacent module in such a way that the last bipolar plate connected to the first module is also connected to the second module, characterised in that: - the mechanical means of attaching the module to the fuel cell and the electrical means of connection are merged; and - the electrical connection means comprise lugs capable of serving also as mechanical fastening means and are arranged to cooperate with metal pins with which the bipolar plates are provided. - at least two voltage measurement modules (1,2), each module being capable of measuring M voltages on a set of contiguous cells of the fuel cell, where M is a natural number less than or equal to N/2, the group of cells measured by the first module being adjacent the group of cells measured by the second module, - an electronic computer, and - a wired communication bus connecting the at least two measuring devices to the computer in series, each of the measurement modules comprising: - mechanical means for attaching the module to the fuel cell, - electronic means of voltage measurement, - electrical means for connecting the bipolar plates to at least one electronic voltage measuring means, - means for connecting the electronic voltage measurement means to the communication bus, - mechanical means for attaching the module to the fuel cell, - electronic means of voltage measurement, - electrical means for connecting the bipolar plates to at least one electronic voltage measuring means, - means for connecting the electronic voltage measurement means to the communication bus, and each module being shaped to cooperate with the adjacent module in such a way that the last bipolar plate connected to the first module is also connected to the second module, characterised in that: - the mechanical means of attaching the module to the fuel cell and the electrical means of connection are merged; and - the electrical connection means comprise lugs capable of serving also as mechanical fastening means and are arranged to cooperate with metal pins with which the bipolar plates are provided. - the mechanical means of attaching the module to the fuel cell and the electrical means of connection are merged; and - the electrical connection means comprise lugs capable of serving also as mechanical fastening means and are arranged to cooperate with metal pins with which the bipolar plates are provided.