Experimental study on the effect of vibration on local reverse polarity and current density distribution in proton exchange membrane fuel cells

Abstract

Vibrations impair the structural stability and water management of proton exchange membrane fuel cells (PEMFCs). This induces uneven current density distribution (CDD) and triggers local reverse polarity (LRP) events. These phenomena further exacerbate performance deterioration and shorten service life. In this work, a cathode-visualized PEMFC integrated with a multi-zone printed circuit board (PCB) is custom-fabricated. By means of visual observation and in-situ measurement, the water distribution, CDD and output performances under different vibration conditions are studied, alongside the impact of long-term vibration on structural integrity. Results indicate that low-frequency vibration enhances water removal and improves the output voltage. At a vibration frequency of 20 Hz, both ohmic and kinetic resistance reach their minima, and the voltage reaches its peak. A further rise in vibration frequency causes membrane dehydration and elevated interfacial contact resistance, resulting in voltage decay. With increasing vibration frequency, the dry area near the inlet gradually expands. The CDD uniformity degrades and the LRP area and intensity increase remarkably. At 30 Hz, the standard deviation of current density increases by 27.89%. Moreover, after 80 h of continuous vibration, the torque of fastening bolts decreases by 15.2%–17.4% and interfacial resistance increases, accompanied by significant deterioration in CDD uniformity.