Electrochemical impedance spectroscopy for investigation of different losses in 4-cells short stack with integrated humidi er and water separator

Electrochemical impedance spectroscopy (EIS) is a suitable and powerful diagnostic testing method for fuel cells (FCs) since it is non-destructive and provides useful information about FC performance and its components. In this study, a 500W cascade type 4 cells stack with integrated humidi er, water separator and internal manifolds was designed, fabricated and tested for the  rst time. The diagnostic test was conducted by EIS. The effects of dead end and open end modes of the stack impedance spectra are studied. The results suggested that ohmic resistance of the single cell decreased as the current density increased due to the greater effect of hydration of membrane. The results of the electrochemical impedance revealed that the gas operating mode had signi cant impact on electrochemical impedance of the stack. When the stack was tested on dead end mode, the charge transfer resistance of the stack decreased dramatically and its in uence on mass transfer resistances was negligible.

کلیدواژه ها:

PEM Fuel Cell (PEMFC) ، Cascade type stack ، Electrochemical Impedance Spectroscopy ، (EIS) ، Dead-end Operation