Method and system for managing a battery device of an electric or hybrid vehicle containing a voltage measurement of the cells connected to an interconnection bar

A method for managing an electric battery device comprising a plurality of modules mounted in series, each comprising a plurality of cells mounted in series, each module being directly electrically connected to at least one other module of the plurality of modules so as to form a pair of modules, with this connection being made via a busbar connected at a cell of each of the modules of the pair, the management method comprising:

• measuring a voltage specific to each cell, whether or not it is connected to a busbar, via slave elements, and measuring the temperature of each module, with each temperature measurement being associated with the one or more busbars connected to the considered module, each slave element comprising a plurality of measurement channels and being connected to the two modules of the considered pair;
• measuring a current flowing through the battery device;
• transmitting the measurements to a processing unit remote from the battery device;
• estimating a voltage compensation value specific to each cell connected to a busbar, the compensation value corresponding to an estimated voltage of the considered busbar for each of said cells, with the compensation value being estimated as a function of the temperature and of the current of the module comprising the considered cell;
• estimating a corrected voltage value specific to each of the cells connected to a busbar by compensating the measured voltage value with the estimated compensation value;
• adjusting and/or determining at least one limiting and/or state parameter of the operation of the battery device as a function of the estimated corrected voltage and/or as a function of the measured voltage.