DC/DC converters are used to match two different DC voltages. In mobile applications, among others, a DC/DC converter can be used to couple electrical power from energy storage devices such as batteries or SuperCap capacitors with volatile voltages to a system with stabilized voltage. Subsequent considerations focus on the advantages of such DC/DC converters, but also take a closer look to the classic disadvantage in the form of efficiency below 100 percent. As we will see, an efficiency of 98 – 99 percent can be achieved with suitable technology and design, so that this disadvantage is surprisingly low. Nevertheless, the advantages and disadvantages of using DC/DC converters must be weighed up in detail. This paper is intended to provide an initial overview in this context