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Showing 1 to 20 of 23 for “"Gas diffusion layer"”.
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Investigation of Water Transport Parameters and Processes in the Gas Diffusion Layer of PEM Fuel Cells
… the water transport characteristics of the gas diffusion 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 …
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Nucleation Dynamics for Water Condensation on Hydrophobic Surfaces in the Presence of Non-Condensable Gases
… However, the presence of non-condensable gas can strongly reduce the nucleation density rate by forming a vapor-depleted gas diffusion layer. Therefore, this work studied the relationship between nucleation density rate and supersaturation ratio during dropwise condensation on subcooled …
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Hybrid fuel cell for mobile devices : an integrated approach
… oxygen and methanol concentration, and cathode gas diffusion layer (GDL) were performed on two standard membrane electrode assemblies (MEA). In addition, an MEA was modified using polyvinyl alcohol (PVA) to test its effect on decreasing methanol crossover for improved fuel cell performance.
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Evaluation of the Effect of Microporous Sublayer Design and Fabrication on Performance and Adhesion in PEM Fuel Cell Assemblies
… exchange membrane fuel cell (PEMFC) contains a layer called the microporous sublayer (MSL). The MSL is a mixture of carbon black and polytetrafluoroethylene (PTFE), which is typically applied to the gas diffusion layer (GDL). The composition (wt.% PTFE) and loading (mg/cm2) can be varied to …
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Free air breathing planar PEM fuel cell design for portable electronics
… cathode electrode, anode electrode, and gas diffusion layer on both sides of the membrane to assume the role of GDL and current collector. This planar fuel cell design was able to produce a power density over 25mW/cm2. This is an order of magnitude lower then reported air breathing fuel …
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Evaluation of the Effects of Microporous Layer Characteristics and Assembly Parameters on the Performance and Durability of a Planar PEM Fuel Cell
… and optimizing the functions of the microporous layer (MPL). Researchers have found that including this layer, composed of carbon black and TeflonTM (PTFE), between the gas diffusion layer (GDL) and catalyst layer (CL) of PEMFCs improves performance. The major benefit of the MPL in conventional …
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Thermal Analysis and Cation Doping of Nafion Membranes
… studied for</p> <p>comparison. Virgin and used gas diffusion layer (GDL), catalyst coated membrane</p> <p>(CCM), and uncatalyzed membrane (UCM) materials were examined to aid in single cell</p> <p>post-test characterization where separation of materials is difficult and may alter results.</p> …
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A comprehensive fractal approach in determination of the effective thermal conductivity of gas diffusion layers in polymer electrolyte membrane fuel cells
… of the effectiveness thermal conductivity of gas diffusion layers (GDL) used in polymer electrolyte membrane fuel cells (PEMFC‟s). This is one of the factors affecting the durability of a fuel cell and need to get a solution to minimize costs and optimize the use of electrodes and cells. The …
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The modification of fuel cell-based breath alcohol sensor materials to improve water retention of sensing performance
… significantly less water. Finally, the catalyst layer and gas diffusion layer (GDL) were investigated. For the catalyst layer, platinum black and 20% platinum supported on carbon achieved similar results. The choice of catalyst was less of an issue than the choice of GDL. It was found that using …
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Water management strategies for polymer electrolyte fuel cells (PEFCs) employing microchannel flowfields
… The build-up of liquid water inhibits reactant gas transport to the catalyst layer, leading to a phenomenon called flooding. Flooding causes a rapid drop in cell voltage and is detrimental to fuel cell performance and durability. Microchannel flowfield designs possess characteristics which could …
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Experimental and numerical analysis of fuel cells
… studies and numerical simulations on PEMFC gas flow channel, the determination of the impact of the single channel fuel cell are presented. Furthermore, preliminary study is done for the application of APS (Air Plasma Spray) to SOFC and adhesion of anode and cathode with electrolytes for the …
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Porous titanium felts as alternative metal gas diffusion layers for low temperature PEM fuel cells
… production. A key component of the PEMFC is the gas diffusion layer (GDL) which facilitates reactant transport and water management within the cell. The GDL is conventionally carbon-based which makes it susceptible to degradation during operation within the oxidative environment of the PEMFC. …
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Carbon Dioxide Capture Conversion via Calgary Framework CALF-20: Catalytic Process design and Optimization
… CO? to ethylene C2H4. Carbon fiber sheet Gas-Diffusion Layer (GDL) was used as a platform to conduct the current and support the MOF and Cu catalyst for CO? capture and electrochemical reduction reaction, respectively. One side of the GDL was coated with Zinc-based MOF. The MOF layer …
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Interfacial Transport Phenomena of the Non-Wetting Phase in Porous Media: Applied to Polymer Electrolyte Fuel Cell Gas Diffusion Media
… experiments applied to water transport in the gas diffusion layer of polymer electrolyte fuel cells (PEFCs). </p> <p>Evidence of a region of gradual property change between the microporous layer and macroporous layer of bi-layer diffusion media is presented, and a mathematical model describing …
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Development and validation of a computational model for a proton exchange membrane fuel cell
… within the polymer portion of the catalyst layers, and liquid water production and transport. Both two-dimensional and three-dimensional geometries are modeled. For a given geometry, the governing differential equations are solved over a single computational domain. For the two-dimensional …
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Growth and use of Carbon Nanotube Nanoforests as Gas Diffusion Layers in Industrial-Scale Proton Exchange Membrane Fuel Cells
… a variety of factors including cell temperature, gas flow rates, reactant humidification, and water management. Water management is especially challenging involving a fine balance between adequate humidification for conductivity and flooding due to excess water. Gas diffusion layers are a …
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Computational fluid dynamics modelling of PEM fuel cells to investigate transport limitations.
… cells and electrochemical reactions at catalyst layers to predict cell voltage at an average current density. The average current density and net water transfer coefficient, used to calculate the source terms, were calculated using auxiliary equations and linked to the solver through UDFs. …
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Investigation of Novel Gas Diffusion Media for Application in Pem Fuel Cell Ribbon Assemblies
… The fuel cell ribbon architecture relies on the gas diffusion layer (GDL) to conduct electrical current in-plane to adjacent cells or collector terminals. The potential advantages of the fuel cell ribbon architecture with respect to conventional fuel cell stacks include reduced manufacturing …
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