battery system with battery voltage measurement has reduced consumption

The invention relates to a system (1) for accumulator battery, comprising: -the first and second stages of accumulators (41, 42); -a first control device (31) supplied by the first stage (41); -a second control device (32) fed by the second stage (42) configured to apply, at an output interface, a digital sequence encoding a measured potential difference; -a communication circuit (6) through which the output interface (322) communicates with an input interface (311); -a power supply circuit (313), a control interface (314) of the switch (315) being connected so that the maintenance of at least one logic level at said output interface (322) involves applying of said power supply on said first control device (31); -a control circuit (317) for selectively controlling the power failure of said first control device (31).