Power losses and their consequences in the addition of storage cells have the negative effect of decreasing the power density and the efficiency in Electric Vehicles. For this reason, an efficiency optimization methodology is required to help reduce that problem. Specifically, in the power converters that interface the storage unit with the electric motors and their inverters, an efficiency optimization is essential to reduce the power losses and thereby downsize the cooling components and the storage unit. In this work, the topology under evaluation is the two-phase interleaved boost converter using different magnetic components such as coupled and non-coupled inductors, which are topologies known as effective for high power density applications. This paper presents a methodology that optimizes the efficiency of the chosen topologies through a complete power loss modeling of each component. Next generation components such as Super Junction Mosfets, GaN and SiC diodes and Mosfets are compared to obtain the most efficient and suitable material to be implemented to the topologies, especially to the converter with coupled-inductor. Moreover, a design procedure is proposed to integrate the loss model and the characteristics of the selected components as the base to obtain the objective function, which is later solved using analytical calculations. Finally, the optimization methodology is validated by experimental tests.