Parameter Estimates for a PEMFC Cathode

Parameter Estimates for a PEMFC Cathode

A Steady-State Impedance Model for a PEMFC Cathode

A model for the simulation of the steady-state impedance response of a polymer electrolyte membrane fuel cell ~PEMFC! cathode is presented. The catalyst layer of the electrode is assumed to consist of many flooded spherical agglomerate particles surrounded by a small volume fraction of gas pores. Stefan-Maxwell equations are used to describe the multicomponent gas-phase transport occurring in b...

Numerical Simulation of the Interfacial Oxygen Transport Resistance for a PEMFC Cathode Incorporating Water Droplet Coverage

The transport resistance of oxygen in a PEMFC flow field and gas diffusion layer interface was numerically investigated in a 3D model. This model solved for the convection of air and the diffusion of oxygen in the air in a single flow field channel. The interfacial oxygen transport resistance was expressed with the Sherwood number. For a dry channel, the numerically obtained Sherwood number was...

Computational analysis of heat and mass transfer in a micro-structured PEMFC cathode

This paper presents a two-dimensional computational model of micro-structured cathodic electrodes featuring nano-porous gas diffusion media that increase the surface to volume ratio of the deposited catalyst layer. A key objective of the modeling effort is to elucidate the Knudsen diffusion within the nano-porous electrode. In addition, the model is non-isothermal and resolves the natural conve...

Study of Ionic Conductivity Profiles of the Air Cathode of a PEMFC by AC Impedance Spectroscopy

A characterization of the ionic conduction of the active layer of a polymer electrolyte membrane fuel cell ~PEMFC! cathode by ac impedance measurement at open-circuit potential conditions was conducted. Porous electrode theory was used to derive a compact equation, ]2F& 2 /]y 1 ] ln f(y)/]y 3 ]F& 2 /]y 2 R/ f (y)(1 1 jV)F& 2 5 0, to solve for the impedance response of a cathode at open-circuit ...