Electrochemical Phenomena in the Cathode Impedance Spectrum of PEM Fuel Cells

Electrochemical Phenomena in the Cathode Impedance Spectrum of PEM Fuel Cells: Fundamentals, Modelling, and Applications establishes how the electrochemical and diffusion mechanisms of a polymer electrolyte membrane fuel cell (PEMFC) are related to electrochemical impedance spectroscopy (EIS) measurements using physics-based impedance models derived from fundamental electrode and diffusion theories. The contribution of the different phenomena occurring at the different layers comprising the cathode on the impedance response of the PEMFC is revealed through EIS-modelling analysis. The relation between EIS measurements and polarisation curves representing the performance of PEMFCs is established. Insight is gained into how the EIS response of the PEMFC changes at different operating conditions e.g. relative humidity, load demand, gas reactant stoichiometry and temperature using physics-based impedance models. The application of impedance models with EIS measurements carried out in the individual cells comprising a PEMFC stack is demonstrated, while recent modelling approaches and other impedance models reported in the literature to represent the EIS response of the PEMFC are also considered and discussed. - Provides further understanding of ambiguities during the interpretation of the electrochemical impedance spectrum of the PEMFC - Includes impedance models written in MATLAB® for replication or application to other PEMFC-EIS measurements - Includes impedance spectra of the PEMFC at different operating conditions, electro/diffusion pathways for derivation of the impedance models and flowcharts for application of the impedance models with real-world measured EIS data

Dr. Samuel Cruz-Manzo is a research fellow from the University of Lincoln, UK with a solid understanding of electrochemical impedance spectroscopy (EIS) in polymer electrolyte membrane fuel cells (PEMFCs) and has also worked with EIS and modelling in Nickel-metal hydride and Lithium-ion batteries. Dr. Cruz-Manzo has experience in real-time dynamic modelling and diagnostic of failures in industrial gas turbines on projects funded by Siemens Energy, Lincoln, UK and previously worked as a simulation engineer at a UK fuel cell company (Intelligent Energy Ltd.). He obtained his PhD degree at Loughborough University UK with a research project related to EIS modelling in PEMFCs. During his PhD study Dr. Cruz-Manzo obtained a prestigious international student research award in Fuel Cells, the Fuel Cell Baker Award 2013, USADr. Paul Greenwood is a research engineer from the Abastecedora Electrica Tehuacan, Mexico and his interests include the performance analysis of electrochemical systems through EIS and modelling. Dr. Greenwood has obtained a PhD degree in Loughborough University UK with a research project related to enhancement of flow field plates in PEMFCs.

Part I. Fundamentals of PEM Fuel Cells and EIS1. Introduction to Electrochemical Impedance Spectroscopy2. Fundamentals of PEM Fuel Cells3. Electrochemical Impedance Spectroscopy in PEM Fuel CellsPart II. Modelling4. Impedance Model of the Cathode Catalyst Layer5. Impedance model of the Cathode Electrode6. Inductive loops at low frequencies of the impedance spectrumPart III. Modelling Application7. Electrochemical phenomena represented in the cathodic impedance spectrum8. Performance analysis in the individual cells of a PEMFC stack through an EIS-Modelling ApproachAppendix.A.1 Fast Fourier algorithm for validation of EIS data, (Chapter 3)A.2 Graphic user interface in Matlab® to fit the PEMFC impedance model with EIS measurements (Chapters 7 and 8)