Onboard installation and method for providing/collecting electric power and automotive vehicle equipped with such an installation

This onboard installation (6-20) is for providing electric power (P) to electric loads (30-36) and collecting power from electric generators (4) of an automotive vehicle (2), the electric loads and generators being connected to a power line (6). The installation includes several independent batteries (10) connected in parallel to the power line (6), one DC/DC converter (16) per battery, the DC/DC converter being connected between battery cells (12) of the battery and the power line, and control means (17) integrated within each DC/DC converter for controlling electric power transfer from the battery cells (12) to the power line (6) and from the power line to the battery cells according to a control scheme. Supervising means (20) are provided for adapting (S 20 ) the control schemes of the DC/DC converters (16) on the basis of the respective states of charge of the batteries (10).