The objective of this paper is to propose an approach to analyze the reliability of proton exchange membrane fuel cell and backup battery in the power electronic systems by improving the strategy of energy management. This approach is based on the research of critical causes generating the degradation of power sources in the power electronic application and their undesirable effect. The analysis of potential failure modes that affect the fuel cell and the auxiliary source is developed by using analysis tools such as the Failure Mode and Effects Analysis (FMEA). The undesirable factors have to be taken into account in designing the topology of power converter in order to improve the performance of a fuel cell power system. In this context the authors propose to integrate a multiphase converter to minimize the current ripple and ameliorate the dynamic response of exchange membrane fuel cell. The improvement of battery lifetime is also ensured by the incorporation of an appropriate charge cycle that promises the full state of charge and avoids the overcharge. (C) 2016 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.