Accelerated Aging Test and Performance Recovery Analysis of PEMFC Stack

Abstract:

Accelerated degradation test (ADT) of a homemade kW level proton exchange membrane fuel cell (PEMFC) stack was conducted under drive cycle. The stack performance degradation was observed, as expected, with the help of polarization curve, electrochemical impedance spectrum (EIS) and V t curve. Scanning electron microscope (SEM) and transmission electron microscope (TEM) were applied to characterize the fresh and post experiment membrane electrode assemblies. The results show that after 603 h ADT, the max power output drops 21.6%. Meanwhile, the phenomenon of recoverable degradation after “rest” was preliminarily analyzed by virtue of EIS and equivalent circuit analysis. It is found that the values of constant phase angle element and faradic impedance get partly recovered, which implies that the recovery of the activity of catalyst and the hydrothermal environment in fuel cell reach an ideal condition before next cold start.

Key words:proton exchange membrane fuel cell(PEMFC); drive cycle; accelerated degradation test (ADT); performance recovery