Equivalent Circuit Modeling of PEM Fuel Cell Degradation Combined With a LFRC

This approach investigates with an equivalent circuit modeling a polymer electrolyte membrane (PEM) fuel cell degradation combined with a low-frequency ripple current (LFRC) that may shorten the fuel cell life and worsen the fuel efficiency. Through the immediate measurement of the impedance curves on single cells obtained after cycling for hours and operating in cathode flooding and membrane dehydration modes at variable frequencies, it has been shown that the impedance magnitude of a fuel cell injecting a LFRC increased when compared with that of a high-frequency ripple current. This study develops these investigations one step further by designing equivalent circuit elements like resistance and capacitance by electrochemical impedance spectroscopy. Impedance-based model is able to describe the dynamic behavior of the PEM fuel cell. For validation of the proposed fuel cell model, an experimental study has been carried out for a 1.2-kW Nexa module.