Download or read book Fully Hydrocarbon Ionomer Catalyst Layers in Proton and Anion exchange Membrane Fuel Cells written by Benjamin Britton and published by . This book was released on 2018 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt: The structure and morphology of fuel cell catalyst layers and concomitant system properties, particularly mass transport, were investigated through electrochemical and physical characterization techniques. Catalyst layers designed for proton-exchange membrane fuel cells (PEMFCs) incorporated a hydrocarbon ionomer (sP4c) soluble in low-boiling solvents. These were used to probe the property alterations effected by increasing ionomer coverage within the catalyst layer, and also to measure the impact an extremely small quantities (0.38 wt%) of a commonly employed high-boiling solvent, DMF, in the catalyst ink. High-boiling solvents are difficult to eliminate during electrode formation, and resultant solvent-annealed catalyst layers lost electrocatalytic surface area, resulting in markedly greater kinetic losses compared to catalyst layers formed without high-boiling solvents. Catalyst layers designed for anion-exchange membrane fuel cells (AEMFCs) incorporating hydrocarbon ionomer in the catalyst layer (FAA-3) requiring high-boiling solvent (NMP, 2.3 wt% of total solvent) were formed over a broad array of conditions. Catalyst layers formed slowly at high temperatures to drive off high-boiling solvent displayed significantly enhanced mesoporosity, relating to enhanced transport characteristics, over solvent-annealed analogues with low mesoporosity, despite comparable total volumes. The impacts of solvent annealing on AEMFC electrode properties and resultant achievable power density and degradation were disproportionate compared to the similar PEMFC study. A new methodology for fuel cell membrane-electrode assembly construction, direct membrane deposition (DMD), enables lower interfacial resistances and enhanced water transport for a given thickness of membrane. These are desired properties for both PEMFCs and AEMFCs. Initially developed with inkjet printers designed for single-cell biological printing applications, this method was adapted to spray-coating systems in order to address issues with fuel and electrical crossover, suitability for hydrocarbon ionomers, and scalability / large-scale reproducibility. A perfluorinated sulfonic acid ionomer reference material (Nafion D520) was employed for direct comparison to initial methods. Highly reproducible DMDs with low fuel and electrical crossover resulted.
Download or read book Improving the Efficiency of Fully Hydrocarbon based Proton exchange Membrane Fuel Cells by Ionomer Content Gradients in Cathode Catalyst Layers written by Hien Nguyen and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Recently, the cell performances of fully hydrocarbon-based fuel cells approached those of cells with perfluorinated ionomers. Most studies used a low catalyst layer ionomer content (∼10 wt%) to enable the highest performance. However, such low ionomer contents can cause a lower cell performance, especially under application-relevant, i.e. reduced humidities (≤50% relative humidity). This work systematically investigates ionomer content gradients in cathode catalyst layers based on hydrocarbon ionomer. A graded ionomer content in the catalyst layer with a higher ionomer content in the vicinity of the membrane (I/C = 0.4, 25% of total layer) and a lower ionomer content (I/C = 0.2, 75% of entire layer) near the gas diffusion layer was found to ensure sufficient proton conductivity without compromising reactant transport. In single-cell tests at hot and dry operation conditions (H2/air, 95 °C and 50% RH), the graded layer enabled both significantly improved current density at relevant cell potentials vs. a monolithic catalyst layer (496 mA cm−2vs. 367 mA cm−[email protected] V) and slightly increased peak performance (0.76 W cm−2vs. 0.71 W cm−2). Under the given conditions, the performance of the graded layer is similar to that of a Nafion catalyst layer. At 80% RH, the hydrocarbon-graded catalyst layer outperforms the Nafion catalyst layer at high current densities
Download or read book Optimization and Characterization of Proton exchange Membrane Fuel Cells Based on Novel Hydrocarbon Ionomers written by Hien Nguyen and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Hydrogen is a critical energy carrier for defossilising the transportation sector. Proton-exchange membrane (PEM) fuel cells represent a pivotal technology for heavy-duty vehicles, in particular. These fuel cells enable the conversion of hydrogen into electrical energy, with the only by-product being water. State-of-the-art PEM fuel cells rely on perfluorosulfonic acid (PFSA) as cation-exchange material. The synthesis of PFSAs is complex, hazardous and expensive, which limits their production to a few select facilities globally, driving up costs even at high volumes. In recent years, there has been a growing concern over the high level of irreversible environmental damage caused by perfluorinated substances. Leading corporations, such as DuPont and 3M, have faced numerous lawsuits for over a decade. To address these concerns, 3M announced in December 2022 that it would exit the perfluorinated substances business by the end of 2025. An alternative to PFSAs is hydrocarbon ionomers, which offer potentially lower material costs, high thermo-mechanical stability at high operating temperatures, and reduced environmental concerns. While replacing PFSA with hydrocarbon ionomers can make fuel cells more sustainable, it has been observed in earlier studies to compromise performance. The primary objective of this study was to bridge the performance and knowledge gap between hydrocarbon and PFSA-based PEM fuel cells. This was achieved by employing a recently commercialized ionomer called "Pemion". Leveraging this innovative material, this work succeeded in developing a fully hydrocarbon-based fuel cell with outstanding performance, representing a significant breakthrough in 2021. To realize this outcome, the study began with a comprehensive literature review,[1] that identified the most significant limitations associated with hydrocarbon-based fuel cells and proposed strategies for their future commercialization. Systematic know-how transfer was then implemented from the field of PFSA-based materials, encompassing process adaptations and extensive optimization of the catalyst layer to advance towards the state-of-the-art performance of PFSA-based fuel cells. A combination of an ultra-thin monolithic membrane (7 μm) and an optimized ink composition with a platinum-cobalt catalyst enabled a comparable peak performance (> 2 W cm-2) to state-of-the-art PFSA reference cell under optimized laboratory conditions: H2/O2, 80 °C, fully humidified gases and ambient pressure. Electrochemical characterizations under various operating conditions show that the hydrocarbon-based cells' performance is more sensitive to changes in relative humidity than the PFSA reference cell.[2] Based on the proof-of-concept, two follow-up improvement pathways have been identified to improve performance and understanding in hydrocarbon-based fuel cells. First, ionomer gradient catalyst layers have been introduced for hydrocarbon-based fuel cells.[3] A two-fold higher ionomer content compared to the optimized one in 25 % of the catalyst layer at the membrane interface improved the performance by up to 35 % in application-relevant conditions, i.e. reduced humidity, while maintaining high peak performance under the same conditions. Second, different conditioning procedures were investigated on hydrocarbon-based fuel cells for the first time. A novel conditioning procedure developed for hydrocarbon-based fuel cells was found to improve the typically lower performance at low current densities of hydrocarbon-based fuel cells the most efficiently.[4] Based on the findings, fuel cells that use Pemion have been shown to perform similarly to those that use PFSA, but further improvements are required for their application in fuel-cell electric vehicles. To continue improving these fuel cells, it is important to find a balance between effective proton conductivity and mechanical integrity of the ionomer in the catalyst layer for efficient performance under different humidity levels. Reference: [1] Hien Nguyen, Carolin Klose, Lukas Metzler, Severin Vierrath, and Matthias Breitwieser. Fully hydrocarbon membrane electrode assemblies for proton exchange membrane fuel cells and electrolyzers: An engineering perspective. Advanced Energy Materials, 12(12):2103559, 2022. doi:10.1002/aenm.202103559. [2] Hien T. T. Nguyen, Florian Lombeck, Claudia Schwarz, Philipp A. Heizmann, Michael Adamski, Hsu-Feng Lee, Benjamin Britton, Steven Holdcroft, Severin Vierrath, and Matthias Breitwieser. Hydrocarbon-based pemionTM proton exchange membrane fuel cells with state-of-the-art performance. Sustainable Energy & Fuels, (5):3687-3699, 2021. doi:10.1039/D1SE00556A. [3] Hien T. T. Nguyen, Dilara Sultanova, Philipp A. Heizmann, Severin Vierrath, and Matthias Breitwieser. Improving the efficiency of fully hydrocarbon-based proton-exchange membrane fuel cells by ionomer content gradients in cathode catalyst layers. Materials Advances, 2022. doi:10.1039/d2ma00761d. [4] Hien Nguyen, Julian Stiegeler, Hannes Liepold, Claudia Schwarz, Severin Vierrath, and Matthias Breitwieser. A comparative study of conditioning methods for hydrocarbon-based proton-exchange membrane fuel cells for improved performance. doi:https://doi.org/10.1002/ente.202300202
Download or read book Experimental Methods and Data Analyses for Polymer Electrolyte Fuel Cells written by K. R. Cooper and published by . This book was released on 2007-07-01 with total page 149 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Characterization Study on Catalyst Layers in Proton Exchange Membrane Fuel Cells written by Luyue Li and published by . This book was released on 2016 with total page 201 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis describes the work for the catalyst layer (CL) characterization study of proton exchange membranes (PEM) for fuel cells. In particular, both the structure and performance of catalyst layers with alternative ionomers were studied. Structure wise, the morphology, surface area and pore size distribution studies were accomplished with scanning electron microscopy (SEM), transmission electron microscope (TEM) and nitrogen adsorption processed through Brunauer--Emmett--Teller (BET) and Barrett- Joyner-Halenda (BJH) theory. Water uptake isotherms of the CLs have been developed under well controlled relative humidity (RH) levels. The performance characterization focuses on polarization study, catalyst layer proton conductivity measurement and estimation of the proton conduction tortuosity. Also, a thermal investigation between various components of the catalyst layer was performed. Two different sets of CLs were examined, the in-house fabricated 3M ionomer CLs and free-standing 3M CLs directly provided from the 3M Company. A characteristic comparison of the structure and electrochemical performance have been carried out, along with further discussion on the formation of CLs containing 3M polytetrafluoroethylene (PTFE) ionomer. Our data revealed that higher ionomer to carbon (I/C) ratio reduced the amount of micro- , meso- and macropores. This allowed the construction of a more completely developed ionic transport network, however, could potentially hinder the mass transfer. Also, our study showed that higher Pt:C ratio lead to a more intense Pt agglomeration. The CL's porosity was strongly affected by such Pt clustering. Furthermore, energy dispersive X-ray analysis (EDS) revealed that the 3M ionomer preferred attaching to the carbon surface over the Pt particles. According to our polarization study, in contrast of tradition Nafion fuel cells, the 3M fuel cells reached its optimal performance at 60%-70% RH and suffered dramatic mass transfer losses at saturated humidity level. Therefore, the 3M fuel cells are able to function fully under drier conditions than the Nafion units. However, the high sensitivity on the cells' water content requires efficient water management during operation, especially at higher current density. Polarization study also showed an optimal 3M ionomer loading of 36 wt.% at 30:70 Pt:C ratio, which is similar to traditional Nafion fuel cells.
Download or read book Polymer Electrolyte Fuel Cell Durability written by Felix N. Büchi and published by Springer Science & Business Media. This book was released on 2009-02-08 with total page 489 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book Factors Influencing Electrochemical Properties and Performance of Hydrocarbon Based Ionomer PEMFC Catalyst Layers written by Toby Duncan Astill and published by . This book was released on 2008 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work investigated the properties of catalyst layers for proton exchange membrane fuel cells (PEMFC) that contained sulfonated poly(ether ether ketone) (SPEEK). A series of SPEEK polymers were prepared with varying ion exchange capacity (IEC) to test their oxygen mass transport properties, electrochemical kinetic parameters, proton conductivity, and water sorption characteristics. A simple method to fabricate catalyst layers containing SPEEK and polytetrafluoroethylene (PTFE) was developed. Catalyst layers were analyzed using scanning electron microscopy (SEM), mercury porosimetry and contact angle determination. Electrochemical characterization in an operating fuel cell was performed using current-potential polarization, cyclic voltammetry, and electrochemical impedance spectroscopy. Electrochemical oxygen reduction in SPEEK membranes was examined in a solid-state electrochemical cell, which allowed determination of oxygen mass transport properties and kinetic parameters. The oxygen diffusion coefficient and permeability was found to increase with increasing ion exchange capacity (IEC), while the solubility of oxygen correspondingly decreased, these trends are due to an increase in water content with increasing IEC. In comparison to perfluorinated electrolytes, such as Nafion®, SPEEK exhibited a lower permeability of oxygen due to a considerably lower solubility of oxygen. A decrease in fuel cell performance was observed when SPEEK was employed in the cathode catalyst layer as the proton conducting medium. The fuel cell current density showed a strong dependence on the method of fabrication of the catalyst layer and the content of SPEEK. Compared to Nafion®-based catalyst layers, SPEEK catalyst layers were found to suffer from low electrochemically active surface area (ESA) and low ionic conductivity. The weight content of SPEEK electrolyte was found to strongly influence the mass transport limited current density.
Download or read book Fuel Cells and Hydrogen Production written by Timothy E. Lipman and published by Springer. This book was released on 2018-10-05 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The expected end of the “oil age” will lead to increasing focus and reliance on alternative energy conversion devices, among which fuel cells have the potential to play an important role. Not only can phosphoric acid and solid oxide fuel cells already efficiently convert today’s fossil fuels, including methane, into electricity, but other types of fuel cells, such as polymer electrolyte membrane fuel cells, have the potential to become the cornerstones of a possible future hydrogen economy. This handbook offers concise yet comprehensive coverage of the current state of fuel cell research and identifies key areas for future investigation. Internationally renowned specialists provide authoritative introductions to a wide variety of fuel cell types and hydrogen production technologies, and discuss materials and components for these systems. Sustainability and marketing considerations are also covered, including comparisons of fuel cells with alternative technologies.
Download or read book Fuel Cells written by Klaus-Dieter Kreuer and published by Springer Science & Business Media. This book was released on 2012-12-14 with total page 795 pages. Available in PDF, EPUB and Kindle. Book excerpt: The expected end of the “oil age” will lead to increasing focus and reliance on alternative energy conversion devices, among which fuel cells have the potential to play an important role. Not only can phosphoric acid and solid oxide fuel cells already efficiently convert today’s fossil fuels, including methane, into electricity, but other types of fuel cells, such as polymer electrolyte membrane fuel cells, have the potential to become the cornerstones of a possible future hydrogen economy. Featuring 21 peer-reviewed entries from the Encyclopedia of Sustainability Science and Technology, Fuel Cells offers concise yet comprehensive coverage of the current state of research and identifies key areas for future investigation. Internationally renowned specialists provide authoritative introductions to a wide variety of fuel cell types, and discuss materials, components, and systems for these technologies. The entries also cover sustainability and marketing considerations, including comparisons of fuel cells with alternative technologies.
Download or read book Polymer Membranes for Fuel Cells written by Javaid Zaidi and published by Springer Science & Business Media. This book was released on 2010-07-15 with total page 439 pages. Available in PDF, EPUB and Kindle. Book excerpt: From the late-1960’s, perfluorosulfonic acid (PFSAs) ionomers have dominated the PEM fuel cell industry as the membrane material of choice. The “gold standard’ amongst the many variations that exist today has been, and to a great extent still is, DuPont’s Nafion® family of materials. However, there is significant concern in the industry that these materials will not meet the cost, performance, and durability requirementsnecessary to drive commercialization in key market segments – es- cially automotive. Indeed, Honda has already put fuel cell vehicles in the hands of real end users that have home-grown fuel cell stack technology incorporating hydrocarbon-based ionomers. “Polymer Membranes in Fuel Cells” takes an in-depth look at the new chem- tries and membrane technologies that have been developed over the years to address the concerns associated with the materials currently in use. Unlike the PFSAs, which were originally developed for the chlor-alkali industry, the more recent hydrocarbon and composite materials have been developed to meet the specific requirements of PEM Fuel Cells. Having said this, most of the work has been based on derivatives of known polymers, such as poly(ether-ether ketones), to ensure that the critical requirement of low cost is met. More aggressive operational requi- ments have also spurred the development on new materials; for example, the need for operation at higher temperature under low relative humidity has spawned the creation of a plethora of new polymers with potential application in PEM Fuel Cells.
Download or read book Control of Ionomer Distribution and Porosity in Roll to Roll Coated Fuel Cell Catalyst Layers written by and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: As fuel cells transition from the laboratory to industrial production for vehicles and other applications there is a need to understand how manufacturing processes impact the properties and, ultimately, the performance of materials. Roll-to-roll coating enables processing at meters per second speeds with physics that can be quite different from common laboratory coating methods. In this work, we have focused on the coating of catalyst layers for proton exchange membrane fuel cells. Commonly, laboratory samples are prepared using spray coating or hand painting, which effectively coat many thin layers to achieve the desired catalyst layer thickness. This creates catalyst layers with uniform distributions of materials throughout the thickness of the full catalyst layer. In contrast, roll-to-roll methods, like slot die and gravure, coat the catalyst layer as a single wet film. As the film dries, ink constituents are able to segregate, leading to a heterogeneous distribution of materials through the thickness of the layer. It is also known that solvent and drying rate can affect the morphology of the catalyst layer. Thus, there is a need to understand how ink formulation and the drying process influence the distribution of materials and catalyst layer morphology. Here, we have explored the influence of solvent and drying rate on morphology of roll-to-roll coated catalyst layers. We show the development of the Kelvin probe method as a rapid screening technique for qualitative analysis of ionomer distribution. We also utilize nano X-ray computed tomography to visualize electrode structure and to quantify particle-size and pore-size distributions, thickness-dependent ionomer distribution, tortuosity, and effective transport properties. We find that solvent has a strong influence on ionomer distribution, with less of an effect on porosity. Conversely, drying temperature has a strong influence on porosity, but less influence on ionomer distribution. Finally, we utilize in situ fuel cell performance testing and other advanced diagnostics to quantify the impact of catalyst layer properties on fuel cell performance and demonstrate that roll-to-roll coating is capable of coating high performance catalyst layers in multi-meter lengths. have focused on the coating of catalyst layers for proton exchange membrane fuel cells. Commonly, laboratory samples are prepared using spray coating or hand painting, which effectively coat many thin layers to achieve the desired catalyst layer thickness. This creates catalyst layers with uniform distributions of materials throughout the thickness of the full catalyst layer. In contrast, roll-to-roll methods, like slot die and gravure, coat the catalyst layer as a single wet film. As the film dries, ink constituents are able to segregate, leading to a heterogeneous distribution of materials through the thickness of the layer. It is also known that solvent and drying rate can affect the morphology of the catalyst layer. Thus, there is a need to understand how ink formulation and the drying process influence the distribution of materials and catalyst layer morphology. Here, we have explored the influence of solvent and drying rate on morphology of roll-to-roll coated catalyst layers. We show the development of the Kelvin probe method as a rapid screening technique for qualitative analysis of ionomer distribution. We also utilize nano X-ray computed tomography to visualize electrode structure and to quantify particle-size and pore-size distributions, thickness-dependent ionomer distribution, tortuosity, and effective transport properties. We find that solvent has a strong influence on ionomer distribution, with less of an effect on porosity. Conversely, drying temperature has a strong influence on porosity, but less influence on ionomer distribution. Finally, we utilize in situ fuel cell performance testing and other advanced diagnostics to quantify the impact of catalyst layer properties on fuel cell performance and demonstrate that roll-to-roll coating is capable of coating high performance catalyst layers in multi-meter lengths.
Download or read book Control of Ionomer Distribution in Roll to Roll Coated Fuel Cell Catalyst Layers written by and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fuel cell catalyst layers are a complex mixture of catalyst particles and ion-conducting polymers. The performance of catalyst layers is highly dependent on microstructure, which must balance proton and electron conduction with gas transport. As fuel cells transition from the laboratory to industrial production for vehicles and other applications, there is a need to understand how manufacturing processes impact the microstructure and, ultimately, the performance of catalyst layers. In this work, we have focused on the roll-to-roll coating of catalyst layers for proton exchange membrane fuel cells. The catalyst layers are responsible for the electrochemical reactions that enable power production. In these devices the catalyst is commonly a Pt nanoparticle supported on porous carbon blacks. The ion conducting polymer, or ionomer, is typically a perfluorosulfonic acid. The most common being Nafion. To fabricate the catalyst layer, the catalyst particles are dispersed in an ink with the ionomer and cast to form the catalyst layer. Commonly, laboratory samples are prepared using spray coating or hand painting, which effectively coat many thin layers to achieve the desired catalyst layer thickness. This creates catalyst layers with uniform distributions of materials throughout the thickness of the full catalyst layer. In contrast, roll-to-roll methods, like slot die, gravure or screen printing, coat the catalyst layer as a single wet film. As the film dries, ink constituents are able to segregate, leading to a heterogeneous distribution of materials through the thickness of the layer. It is also known that the choice of solvent and drying rate can affect the morphology of the catalyst layer. Thus, there is a need to understand how ink formulation and the drying process influence the distribution of materials and catalyst layer morphology. Here, we have explored the influence of solvent and drying rate on morphology of roll-to-roll coated catalyst layers. We show the development of the Kelvin probe method as a rapid screening technique for qualitative analysis of ionomer distribution. We also utilize nano X-ray computed tomography to visualize electrode structure and to quantify particle-size and pore-size distributions, thickness-dependent ionomer distribution, tortuosity, and effective transport properties. We find that solvent has a strong influence on ionomer distribution, with less of an effect on porosity. Conversely, drying temperature has a strong influence on porosity, but less influence on ionomer distribution. Finally, we utilize in situ fuel cell performance testing and other advanced diagnostics to quantify the impact of catalyst layer properties on fuel cell performance and demonstrate that roll-to-roll coating is capable of coating high performance catalyst layers in multi-meter lengths.
Download or read book Proton Exchange Membrane Fuel Cells 6 written by Thomas Francis Fuller and published by The Electrochemical Society. This book was released on 2006 with total page 1385 pages. Available in PDF, EPUB and Kindle. Book excerpt: The symposium was devoted to all aspects of research development and engineering of proton exchange membrane fuel cells. Three subareas were covered: materials and electrode processes, fuel cell systems, and durability.
Download or read book Proton Conducting Membrane Fuel Cells II written by Shimshon Gottesfeld and published by The Electrochemical Society. This book was released on 1999 with total page 524 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Polymer Electrolyte Fuel Cell Degradation written by Matthew M. Mench and published by Academic Press. This book was released on 2012 with total page 474 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book PEM Fuel Cells written by Yun Wang and published by Momentum Press. This book was released on 2013-04-06 with total page 450 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polymer Electrolyte Membrane (PEM) fuel cells convert chemical energy in hydrogen into electrical energy with water as the only by-product. Thus, PEM fuel cells hold great promise to reduce both pollutant emissions and dependency on fossil fuels, especially for transportation—passenger cars, utility vehicles, and buses—and small-scale stationary and portable power generators. But one of the greatest challenges to realizing the high efficiency and zero emissions potential of PEM fuel cells technology is heat and water management. This book provides an introduction to the essential concepts for effective thermal and water management in PEM fuel cells and an assessment on the current status of fundamental research in this field. The book offers you: • An overview of current energy and environmental challenges and their imperatives for the development of renewable energy resources, including discussion of the role of PEM fuel cells in addressing these issues; • Reviews of basic principles pertaining to PEM fuel cells, including thermodynamics, electrochemical reaction kinetics, flow, heat and mass transfer; and • Descriptions and discussions of water transport and management within a PEM fuel cell, including vapor- and liquid-phase water removal from the electrodes, the effects of two-phase flow, and solid water or ice dynamics and removal, particularly the specialized case of starting a PEM fuel cell at sub-freezing temperatures (cold start) and the various processes related to ice formation.
Download or read book PEM Water Electrolysis written by Dmitri Bessarabov and published by Academic Press. This book was released on 2018-08-04 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt: PEM Water Electrolysis, a volume in the Hydrogen Energy and Fuel Cell Primers series presents the most recent advances in the field. It brings together information that has thus far been scattered in many different sources under one single title, making it a useful reference for industry professionals, researchers and graduate students. Volumes One and Two allow readers to identify technology gaps for commercially viable PEM electrolysis systems for energy applications and examine the fundamentals of PEM electrolysis and selected research topics that are top of mind for the academic and industry community, such as gas cross-over and AST protocols. The book lays the foundation for the exploration of the current industrial trends for PEM electrolysis, such as power to gas application and a strong focus on the current trends in the application of PEM electrolysis associated with energy storage. Presents the fundamentals and most current knowledge in proton exchange membrane water electrolyzers Explores the technology gaps and challenges for commercial deployment of PEM water electrolysis technologies Includes unconventional systems, such as ozone generators Brings together information from many different sources under one single title, making it a useful reference for industry professionals, researchers and graduate students alike
