Impact of high frequency current ripples on the degradation of high-temperature PEM fuel cells (HT-PEMFC)

Abstract

In order to achieve the goal of reducing the environmental footprint of the transport sector, new low-carbon energy systems including fuel cells and power converters are proposed. The sizing and operation of such systems have to take into account the aging of the fuel cell. This paper focuses on the study of a potential impact of high frequency current ripples (HFCR) on the degradation of a high-temperature proton exchange membrane fuel cell (HT-PEMFC). A 2600 h long endurance test was carried out on 4 HT-PEMFC single cells with and without HFCR. The degradation of two cells operated with a triangular current waveform of frequency 20 kHz and amplitude 20 %pp of the mean current density (0.2 A/cm2) is compared to the degradation of two cells operated at the same constant mean current density. In addition to endurance phase, several characterization phases (polarization curves, electrochemical impedance spectroscopy and cyclic voltammetry) are used to analyse the impact of the current harmonics. The obtained results show that the high frequency current ripples do not seem to accelerate the degradation of the HT-PEMFC single cells.