Study on Reverse Polarization of Proton Exchange Membrane Fuel Cell Stack Caused by Anode Starvation

At present? the study of proton exchange membrane fuel cell(PEMFC? reversal was mainly completed through a single cell? and the reversal process didn't consider the influence of adjacent cells? which was not completely the same as the actual situation of the stack. This paper analyzed the anode starvation reverse polarity of PEMFC stack composed of 5 single cells under water flooding and gas shortage conditions by controlling testing conditions such as humidity and excess coefficient. The results show that under anode water flooding conditions? the voltage of the reverse polarity single cell slowly decreases to the electrolysis level table and then quickly recovers. The reason for performance recovery is that the pressure difference between the inlet and outlet of the water flooded single cell anode increases? causing liquid water to be discharged and hydrogen to enter again. Under the condition of gas shortage in the anode of the stack? the voltage of the reverse pole single cell exhibits a cyclic process of rapidly decreasing to the carbon corrosion platform and then rapidly recovering. The reason for the performance recovery is that the decrease in pressure difference between the anode inlet and outlet of the gas deficient single cell causes a new distribution of hydrogen gas in the stack. Due to the lack of gas? the voltage of the reverse polarity battery will decrease to the carbon corrosion platform? which will cause irreversible damage to the battery performance