Electrical apparatuses, systems and methods involving battery boost circuitry configured to charge a supercapacitor to a regulated voltage different from the battery voltage and apply a series combination of the regulated voltage and the battery voltage to a load such as a starter motor for an internal combustion engine or a component of a handheld device. The circuitry also includes a contactor connected to the supercapacitor and operable to bypass the capacitor when fully discharged to avoid reverse charging of the supercapacitor.