This paper presents an analysis and comparison of isolated topologies for bidirectional fuel cell systems. The analyzed topologies are the dual active bridge (DAB) and the isolated full bridge boost converter (IFBBC). The analysis is performed based on the component stress factor (CSF). Results highlight that the DAB has lower CSF than the IFBBC for narrow converter operating points. On the other hand, the IFBBC presents a more homogeneous CSF over the entire converter operating range. Finally, experimental results obtained from a 30–80 V, 80 A, 6 kW, 40 kHz IFBBC are presented. The converter achieves efficiencies up to 98.2% and 97.45% depending on the converter power flow.