Vehicular power supply system with a super capacitor arranged in parallel with a battery unit for managing peak currents

A vehicular power system includes a battery branch including a battery unit arranged in series with a diode, and a high-capacity unit having a maximum voltage that exceeds a nominal voltage of the battery unit. The battery branch and high-capacity unit are arranged in parallel, to feed a load side of the vehicular power system. The battery branch further includes a switching arrangement configured to disconnect the battery unit in response to excessive load-side current. The switching arrangement may allow the high-capacity unit to inject current into the load side at a voltage less than the nominal voltage of the battery unit and/or may allow the high-capacity unit to absorb regenerated current from the load side at a voltage which is greater than the nominal voltage of the battery unit.