Abstract: A jump starter unit for starting vehicles and other equipment. The jump starter includes DC-to-DC converter and one or more large capacitors (500 Farad or more). The DC-to-DC converter maintains the capacitor's charge when a jump charge is not needed. The DC-to-DC converter and capacitor(s) are integrated into an electrical system that includes an electronic control and a plurality of relays that provide the various charging and jump functions of the unit. The jump starter unit may take the form of a portable or mobile self-contained apparatus having its own lithium battery to provide power to the DC-to-DC converter. The jump starter unit may be integrated into a device with another DC power source to provide power to the jump starter.