Electrochemical Polymer Electrolyte Membranes

Electrochemical Polymer Electrolyte Membranes covers PEMs from fundamentals to applications, describing their structure, properties, characterization, synthesis, and use in electrochemical energy storage and solar energy conversion technologies. Featuring chapters authored by leading experts from academia and industry, this authoritative text: Disc

This volume explores the latest developments in the area of polymer electrolyte membranes (PEMs) used for high-temperature fuel cells. Featuring contributions from an international array of researchers, it presents a unified viewpoint on the operating principles of fuel cells, various methodologies used for the fabrication of PEMs, and issues related to the chemical and mechanical stabilities of the membranes. Special attention is given to the fabrication of electrospun nanocomposite membranes. The editors have consciously placed an emphasis on developments in the area of fast-growing and promising PEM materials obtained via hygroscopic inorganic fillers, solid proton conductors, heterocyclic solvents, ionic liquids, anhydrous H3PO4 blends, and heteropolyacids. This book is intended for fuel cell researchers and students who are interested in a deeper understanding of the organic–inorganic membranes used in fuel cells, membrane fabrication methodologies, properties and clean energy applications.

This book is a comprehensive review of high-temperature polymer electrolyte membrane fuel cells (PEMFCs). PEMFCs are the preferred fuel cells for a variety of applications such as automobiles, cogeneration of heat and power units, emergency power and portable electronics. The first 5 chapters of the book describe rationalization and illustration of approaches to high temperature PEM systems. Chapters 6 - 13 are devoted to fabrication, optimization and characterization of phosphoric acid-doped polybenzimidazole membranes, the very first electrolyte system that has demonstrated the concept of and motivated extensive research activity in the field. The last 11 chapters summarize the state-of-the-art of technological development of high temperature-PEMFCs based on acid doped PBI membranes including catalysts, electrodes, MEAs, bipolar plates, modelling, stacking, diagnostics and applications.

Electrochemical energy systems can successfully exploit beneficial characteristics of electrolyte and/or electrode membranes due to their intriguing peculiarities that make them well-established, standard components in devices such as fuel cells, electrolyzers, and flow batteries. Therefore, more and more researchers are attracted by these challenging yet important issues regarding the performance and behavior of the final device. This Special Issue of Membranes offers scientists and readers involved in these topics an appealing forum to bring and summarize the forthcoming Research & Development results, which stipulates that the composite electrolyte/electrode membranes should be tailored for lithium batteries and fuel cells. Various key aspects, such as synthesis/preparation of materials/components, investigation of the physicochemical and electrochemical properties, understanding of phenomena within the materials and electrolyte/electrode interface, and device manufacturing and performance, were presented and discussed using key research teams from internationally recognized experts in these fields.

The book provides a systematic and profound account of scientific challenges in fuel cell research. The introductory chapters bring readers up to date on the urgency and implications of the global energy challenge, the prospects of electrochemical energy conversion technologies, and the thermodynamic and electrochemical principles underlying the operation of polymer electrolyte fuel cells. The book then presents the scientific challenges in fuel cell research as a systematic account of distinct components, length scales, physicochemical processes, and scientific disciplines. The main part of the book focuses on theory and modeling. Theoretical tools and approaches, applied to fuel cell research, are presented in a self-contained manner. Chapters are arranged by different fuel cell materials and components, and sections advance through the hierarchy of scales, starting from molecular-level processes in proton-conducting media or electrocatalytic systems and ending with performance issues at the device level, including electrochemical performance, water management, durability, and analysis of failure mechanisms. Throughout, the book gives numerous examples of formidable scientific challenges as well as of tools to facilitate materials design and development of diagnostic methods. It reveals reserves for performance improvements and uncovers misapprehensions in scientific understanding that have misled or may continue to mislead technological development. An indispensable resource for scientifically minded and practically oriented researchers, this book helps industry leaders to appreciate the contributions of fundamental research, and leaders of fundamental research to appreciate the needs of industry.

This book covers a significant number of R&D projects, performed mostly after 2000, devoted to the understanding and prevention of performance degradation processes in polymer electrolyte fuel cells (PEFCs). The extent and severity of performance degradation processes in PEFCs were recognized rather gradually. Indeed, the recognition overlapped with a significant number of industrial dem- strations of fuel cell powered vehicles, which would suggest a degree of technology maturity beyond the resaolution of fundamental failure mechanisms. An intriguing question, therefore, is why has there been this apparent delay in addressing fun- mental performance stability requirements. The apparent answer is that testing of the power system under fully realistic operation conditions was one prerequisite for revealing the nature and extent of some key modes of PEFC stack failure. Such modes of failure were not exposed to a similar degree, or not at all, in earlier tests of PEFC stacks which were not performed under fully relevant conditions, parti- larly such tests which did not include multiple on–off and/or high power–low power cycles typical for transportation and mobile power applications of PEFCs. Long-term testing of PEFCs reported in the early 1990s by both Los Alamos National Laboratory and Ballard Power was performed under conditions of c- stant cell voltage, typically near the maximum power point of the PEFC.

For full market implementation of PEM fuel cells to become a reality, two main limiting technical issues must be overcome- cost and durability. This cutting-edge volume directly addresses the state-of-the-art advances in durability within every fuel cell stack component. [...] chapters on durability in the individual fuel cell components -- membranes, electrodes, diffusion media, and bipolar plates -- highlight specific degradation modes and mitigation strategies. The book also includes chapters which synthesize the component-related failure modes to examine experimental diagnostics, computational modeling, and laboratory protocol"--Back cover.