Abstract: A system for charging a motor vehicle battery, configured to be connected to a first multiphase power supply network or to a second multiphase or single phase power supply network of which the power is lower than that of the first network, including: a filtering stage including plural capacitors; a first rectifier stage including switches; and an inverter stage configured to be connected to the battery. The charging system includes: a second rectifier stage including plural switches, and configured to be connected between the power supply network and the battery, in parallel with the filtering stage and at least a portion of the first rectifier stage; and a capacitor of which the capacity is lower than that of the capacitors of the filtering stage, connected between two phases or between a phase and a neutral of the second power supply network.