Effects of Initial Water Content of Membrane on Cold Start Performance of PEMFC

Abstract

The performance degradation of proton exchange membrane fuel cells (PEMFC) in low-temperature extreme environments is one of the challenges on the way to their commercialization, and it is important to investigate the performance changes of fuel cells in low-temperature environments for their future development. In this paper, the cold-start performance of fuel cells with different initial water content of the membrane and starting modes was compared. Lowering the initial water content of the membrane could enhance the water storage capacity of the cell and improve the cold-starting performance of the cell, but infinitely low initial water content might cause the reverse polarity phenomenon, which would cause serious corrosion and degradation of the membrane electrode assembly (MEA). In constant voltage starting mode, reducing the starting voltage could increase the heat production of the cell, but it would weaken the water storage capacity of the cell. In the constant current starting process, lowering the starting current could improve the water storage capacity of the cell, which was beneficial to the cold start of the cell. It was also found that the MEA with cold start failure had a serious performance degradation, and cold start failure needed to be avoided as much as possible.