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Showing 1 to 20 of 53 for “"PEM Fuel Cells"”.
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Understanding of Ammonia Transport In Pem Fuel Cells
… dissertation investigated ammonia (NH3) as a fuel contaminant to the anode in Proton Exchange Membrane Fuel Cells (PEMFCs). Since NH3 is fed to the anode in a gas phase and transferred to the cathode, the effect of a contaminant is distributed through MEA and quite complicated. This study is …
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Transients in Polymer Electrolyte Membrane (PEM) Fuel Cells
… has presented proton exchange membrane (PEM) fuel cells as a potential energy source. The use of PEM fuel cells for automotive and other transient applications, where there are rapid changes in load, presents a need for better understanding of transient behavior. In particular at low …
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Comparative analysis of Polymer Electrolyte Membrane (PEM) fuel cells
… for making the Polymer Electrolyte Membrane Fuel Cells (PEMFC) membranes owing to their extensive intrinsic chemical stability and super sulfonic acid strength which is core to the PEMFC proton conductivity. This thesis presents a deeper analysis into these PFSA ionomer membrane electrode …
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Modelling, simulation and performance evaluation: PEM fuel cells for high altitude UAS
A fuel cell is a device that converts energy in the fuel and reactant into electrical DC power. Fuel cell powered aircraft are generally characterised by a low power to weight ratio (W/kg). The propulsion system of an unmanned aircraft needs a large range of power and fast response to fulfil the …
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Electrochemical Oxidation of Carbon Monoxide in Reformate Hydrogen for PEM Fuel Cells
… the performance of proton exchange membrane fuel cells (PEMFC). Various techniques studied to remove CO from source or mitigate CO poisoning have met with limited success due to fuel loss or increases infrastructure requirements to meet the operating needs. We developed a twin cell …
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Computational fluid dynamics modelling of PEM fuel cells to investigate transport limitations.
… polluting emissions. Proton Exchange Membrane (PEM) fuel cell has shown and demonstrated that potential to be a suitable alternative power source because of its simplicity of design, load following capabilities, efficiency, feasibility and quick start-up. Although having these splendid …
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Development of a semi–empirical reaction kinetic model for PEM fuel cells
… energy production, polymer electrolyte fuel cells (PEFC) have been at the pinnacle of global research. One of the major drawbacks of PEFCs is therequirement for expensive noble metal catalysts (platinum and ruthenium). Furthermore 75% of the overpotential losses at the cathode are due to …
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Development of Tin Oxide As An Oxidation-Resistant Support For Pem Fuel Cells
… of cathode catalysts in proton exchange membrane fuel cells (PEMFCs) is perhaps the most critical issue that hinders the success of PEMFCs application. Specific durability requirements include resistance to corrosion of the catalyst support, stability of the electrochemical surface area against …
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Combining In Situ Measurements and Advanced Catalyst Layer Modeling in PEM Fuel Cells
Catalyst layer modeling can be a useful tool for fuel cell design. By comparing numerical results to experimental results, numerical models can provide a better understanding of the physical processes occurring within the fuel cell catalyst layer. This can lead to design optimization and cost …
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Evaluation of Novel and Low-Cost Materials for Bipolar Plates in PEM Fuel Cells
… the total cost in a polymer electrolyte membrane fuel cell stack. In an attempt to reduce these costs, a novel manufacturing method was developed for use with composite materials. Conductive fillers were mixed with a polypropylene binder and molded into single cell monopolar plates. A fuel cell …
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Advanced FeNC Catalysts for Oxygen Reduction Reactions in PEM Fuel Cells: Synthesis and Performance Evaluation
L'abstract è presente nell'allegato / the abstract is in the attachment
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Porous titanium felts as alternative metal gas diffusion layers for low temperature PEM fuel cells
Proton exchange membrane fuel cells(PEMFCs) use hydrogen to generate electrical energy with water as the only by-product, and are thus highlighted as a key energy conversion technology in the shift towards sustainable energy production. A key component of the PEMFC is the gas diffusion layer (GDL) …
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Investigation of the Effect of Catalyst Layer Composition on the Performance of PEM Fuel Cells
The catalyst layer of a proton exchange membrane (PEM) fuel cell is a porous mixture of polymer, carbon, and platinum. The characteristics of the catalyst layer play a critical role in determining the performance of the PEM fuel cell. In this research, sample membrane electrode assemblies (MEAs) …
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In-situ investigation and mitigation of carbon support corrosion of cathode catalyst in PEM fuel cells
… (Pt/C) degradation in proton exchange membrane fuel cells (PEMFC). It is electrochemical oxidation and thus needs to be investigated in-situ with potential imposed. CSC was characterized in-situ and correlated to the Pt redox reactions and Pt-catalyzed oxygen reduction reaction (ORR) by the …
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Iridium oxide supported on graphitized carbon for use as reversal tolerant anodes in pem fuel cells
… reversal occurs in Proton Exchange Membrane Fuel Cells (PEMFCs) is when the H2 supply is insufficient to meet the load requirements of the cell. During cell voltage reversal, carbon oxidation and water electrolysis occur at the anode to maintain the supply of protons and electrons to the …
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Investigation of Water Transport Parameters and Processes in the Gas Diffusion Layer of PEM Fuel Cells
… layer (GDL) of proton exchange membrane fuel cells (PEMFCs). Additionally, experimental fixtures and procedures for the determination of the constitutive relationships are presented. The water transport relationships are incorporated into analytical models that assess the impact of the …
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Numerical simulation of multi-scale transport processes and reactions in pem fuel cells using two-phase models
A numerical study for the cathode of a PEM fuel cell has been performed in this study. The results have been limited to cathode only because, in PEM fuel cells, the oxygen reduction reactions, ORRs, are considered the rate limiting reactions and govern the fuel cell performance. The modeling …
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