Main content area

Effects of Mg2+ contamination on the performance of proton exchange membrane fuel cell

Zhu, Jingyu, Tan, Jinzhu, Pan, Qing, Liu, Zenghui, Hou, Qiong
Energy 2019 v.189 pp. 116135
X-ray diffraction, anodes, durability, electric potential difference, electrochemistry, energy-dispersive X-ray analysis, fuel cells, hydrogen, hydrogen fuels, ion exchange, ions, magnesium, scanning electron microscopy, spectroscopy, sulfonates, sulfonic acids
Contamination ions from bipolar plates and elastomeric gaskets for degradation play an important role on the long-term stability and durability of proton exchange membrane (PEM) fuel cells. In this paper, the effects of Mg²⁺ contamination on PEM fuel cell performance were investigated experimentally. Five levels of Mg²⁺ concentrations were used in this work. Electrochemical performance tests were performed by adding the various Mg²⁺ concentration solutions into the anode H₂ fuel stream of the PEM fuel cell. And then scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), electron probe microanalysis (EPMA) and X-ray diffraction (XRD) were employed to study degradation mechanism of the PEM fuel cell performance for Mg²⁺ contamination. The test results show that both Mg²⁺ concentration and contamination time had significant effects on PEM fuel cell performance. The voltage and maximum power density of the PEM fuel cell decreased with the increase of Mg²⁺ concentration and contamination time. EDS and EPMA results indicate that the Magnesium mainly appeared in the PEM for the Mg²⁺ contaminating of the PEM fuel cell, and the Magnesium increased with the increasing Mg²⁺ concentration over time. The degradation mechanism of the PEM fuel cell performance for the Mg²⁺ contamination could be due to ion exchange reaction between Mg²⁺ and the proton of sulfonic acid groups in the PEM to form the new sulfonate structure.