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Showing 1 to 20 of 69 for “"PEM fuel cell"”.
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Investigation of Graphite Bipolar Plates for PEM Fuel Cell Performance
The largest cost in manufacturing PEM fuel cells for automotive applications is due to the bipolar plate. The current graphite material used for the bipolar plate is very brittle and difficult to machine to the rigorous specifications needed for fuel cell stacks. This paper introduces the …
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Investigation of Shorting by Penetration in Pem Fuel Cell Membranes
… shorting through the proton exchange membrane (PEM) is a form of early failure commonly found in PEM fuel cells. In order to improve the durability and thus the commercial potential for PEM fuel cells, this form of failure must be understood and mitigated. This research investigates whether …
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Free air breathing planar PEM fuel cell design for portable electronics
PEM fuel cell technology is an energy source that can provide several times more energy per unit volume then current lithium ion batteries. However, PEM fuel cells remain to be optimized in volume and mass to create a minimum size for integration into portable electronics. A planar fuel cell design …
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A Comparison of Two Air Compressors for PEM Fuel Cell Systems
Proton exchange membrane (PEM) fuel cells are considered one of the best potential alternative power sources for automobiles. For this application, high efficiency and high power density are required. Pressurizing the fuel cell system can give higher efficiency, higher power density and better …
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Understanding and Controlling Wettability of Carbon Powders for PEM Fuel Cell Applications
… and lifetime of polymer electrolyte membrane fuel cells (PEMFCs). As the CLs are composed of Pt nanoparticles supported on carbon powders, bound together with Nafion®, the main focus of this work was to understand and control the wettability of carbon materials for their use in PEMFCs. The …
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Analysis of Ionomer-coated Carbon Nanofiber for use in PEM Fuel Cell Catalyst Layers
… layer structure for proton exchange membrane (PEM) fuel cells has changed little over the last two decades. A new electrode design with improved control over factors such as ionic and electrical pathways, porosity, and catalyst placement, could allow the application of less expensive catalyst …
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Investigation of Novel Gas Diffusion Media for Application in Pem Fuel Cell Ribbon Assemblies
A new type of fuel cell architecture, the fuel cell ribbon, is presented. 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 …
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Control and Operation of a Microgrid Involving a PEM Fuel Cell Through Analysis and Experimentation
… an inverter interfaced proton exchange membrane fuel cell (PEMFC) power module and two synchronous generators operating in an islanded mode. The work includes the experimental investigation of the dynamic characteristics of the distributed generators in this prototype microgrid. A control and …
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In situ studies of Pt nanoparticles on different supports for corrosion stable PEM fuel cell cathodes
Wasserstoffbrennstoffzellen bieten als elektrochemische Energiewandler die Möglichkeit, Wasserstoff aus erneuerbaren Resourcen als saubere und emissionsarme Energiequelle für elektrische Verbraucher, wie Elektromotoren, zu nutzen. Um eine konkurrenzfähige Alternative zu heutigen Verbrennungsmotoren …
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Understanding the carbon morphology in sulfonated-silica ceramic carbon electrodes for the PEM fuel cell device
Using hydrogen and oxygen gas, the fuel cell is a device that converts chemical energy into electrical energy. Particularly, the proton exchange membrane fuel cell, has multiple components, all that are consistently being studied in order to further increase its practicality. One particular …
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Water Management in the PEM Fuel Cell by Incorporating a Novel Siloxane Polymer in the Electrode Layer
… the water issue present in Nafion¿¿-based PEM fuel cells operating at low relative humidity conditions by employing a hydrophilic substance COMP-1 in the electrode layer. This modified electrode was hypothesized to prevent the cell from dehydrating by retaining water in the catalyst layer. …
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Experimental Investigation of the Effect of Composition on the Performance and Characteristics of PEM Fuel Cell Catalyst Layers
The catalyst layer of a proton exchange membrane (PEM) fuel cell is a 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. This research investigates the role of catalyst layer composition using …
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Evaluation of the Effect of Microporous Sublayer Design and Fabrication on Performance and Adhesion in PEM Fuel Cell Assemblies
… architecture of the proton 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 …
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Probing the influence of relative humidity and temperature on the sulfonated silica ceramic carbon electrode for PEM fuel cell operation
Operation of fuel cells under low relative humidity (RH) and high temperature is a useful way to cut-down cost and increase performance. However, the Nafion ionomer employed in the electrode of the conventional fuel cells performs poorly under low RH and temperatures above 80 °C due to dehydration. …
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Development of a lithium hydride powered hydrogen generator for use in long life, low power PEM fuel cell power supplies
This thesis studies a hybrid PEM fuel cell system for use in low power, long life sensor networks. PEM fuel cells offer high efficiency and environmental friendliness but have not been widely adopted due to cost, reliability, and the problem of hydrogen storage. This thesis focuses on the problem …
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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
… significant portion of proton exchange membrane fuel cell (PEMFC) work has been focused on understanding 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 …
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Dynamic modeling and control of a proton exchange membrane fuel cell as a distributed generator
… and control of a Proton Exchange Membrane (PEM) fuel cell in a deregulated electric power system. The PEM fuel cell is a Multiple Input Multiple Output (MIMO) system with various dynamic states. In most previous model studies, the stack temperature of a fuel cell was considered to be …
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Experimental investigation of novel proton exchange membrane fuel cell and battery integrated system
In this thesis study, a PEM fuel cell and battery integrated system is developed. The performance assessments of the PEM fuel cell stack are performed through the polarization curve, energy efficiency, exergy efficiency, and open circuit voltage. Furthermore, the performance evaluation of the fuel …
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