Modeling Planar and Self-Breathing Fuel Cells for Use in Electronic Devices

Abstract

A theoretical study of a planar and self-breathing fuel cell is presented. This work contains the development of a mathematical model for planar self-breathing fuel cells, the validation of the model, and a study of the behavior of this type of fuel cell. The mathematical model presented is two-dimensional and nonisothermal. The validation of the model is performed by comparison of the measured overall performance of a planar self-breathing fuel cell to the predictions of the model. For this type of cell, the maximum power density is in the range between 0.5 and 0.4 V, so the model is applied to study the behavior of the reference cell at a cell voltage of 0.4 V. The results of this study show the gas distribution, the potential distribution, and the temperature distribution are influenced strongly by the geometric design of the cathode end plate. The charge generation rate in the active area of the cathode and anode is affected by the ribs of the cathode end plate. A strong nonuniformity of the current distribution in the cathode is found. © 2004 The Electrochemical Society. All rights reserved.

Engineering model of a passive planar air breathing fuel cell cathode

“…Planar air breathing cells are characterized by an open cathode structure that allows ambient air to advect and diffuse to the surface, while simultaneously collecting current from a gas diffusion layer [3,4]. Planar air breathing fuel cells offer the advantage of a flat form factor suitable for small portable applications.…”

Analysis of the Coupling Behavior of PEM Fuel Cells and DC-DC Converters

“…It is fed with air and will be operated in rheostatic mode due to the coupling with the DC-DC converters. Although this fuel cell model is relatively simple and consists only of a single cell with a cross-sectional area of one square centimeter [6,11], the modeling approach is complex enough to analyze and outline the essential qualitative effects due to the coupling between one-phase or two-phase PEM fuel cells and DC-DC converters as we will show during the analysis.…”

“…(1)(2)(3)(4)(5)) and the converters (Eqns. (6)(7)(8)(9)(10)(11)) the following conditions apply: U cell U e and i cell I e /A g .…”

“…However, oscillations are still possible and their appearance has to be analyzed. This is done by coupling and averaging the model equations of the PEMFC (1-3) and the buck-boost converter (10,11) in the same way like in the previous two cases. We obtain the same mass transport equations for oxygen and water vapor like in the case of the buck converter (Eqns.…”

Mathematical modelling of the catalyst layer of a polymer electrolyte fuel cell

“…Though D 2 is likely to fall somewhere between these values, we will later exploit them in an asymptotic analysis as the limits of weak and strong diffusion limitation. Siegel et al(2003), Um et al(2000), Mazumder & Cole (2004), Lin et al (2004), Song et al (2004), Yin (2005), Sun et al (2005), Huang & White (2000), Middelman (2002), Berg et al (2004) and Ziegler et al (2004) With the assumption of electro-neutrality, Ohm's law yields the following equation for the potential in phase 2, φ:…”