Analytical Impedance of Oxygen Transport in a PEM Fuel Cell Channel

Abstract

© 2019 Electrochemical Society Inc. All rights reserved. We report a model for impedance Zh of oxygen transport in a PEMFC channel. Analytical solution for Zh is derived and a simple approximate equation for the summit frequency of Zh arc is obtained. In the limit of zero frequency of AC signal, a rather cumbersome expression for Zh reduces to a simple equation for the cell resistivity due to oxygen transport in the channel: [EQUATION PRESENTED]where b is the ORR Tafel slope per exponential basis, is the stoichiometry of the oxygen (air) flow, and J is the mean current density in the cell.