(Invited) Recent Advances on Energy Conversion Using Microfluidic Fuel Cells Technology, Case: Glucose Membraneless Micro Fuel Cell Stack

2014 ◽  
Vol 64 (3) ◽  
pp. 865-874 ◽  
Author(s):  
F. M. Cuevas-Muniz ◽  
A. U. Chavez ◽  
M. Guerra-Balcazar ◽  
L. A. Godinez Mora-Tovar ◽  
J. Ledesma-Garcia ◽  
...  
Keyword(s):  
Fuel Cells ◽  
Fuel Cell ◽  
Energy Conversion ◽  
Fuel Cell Stack ◽  
Recent Advances

Current progress and performance improvement of Pt/C catalysts for fuel cells

2020 ◽  
Vol 8 (46) ◽  
pp. 24284-24306
Author(s):  
Xuefeng Ren ◽  
Yiran Wang ◽  
Anmin Liu ◽  
Zhihong Zhang ◽  
Qianyuan Lv ◽  
...  
Keyword(s):  
Fuel Cells ◽  
Fuel Cell ◽  
Energy Conversion ◽  
Performance Improvement ◽  
Electric Energy ◽  
Energy Conversion Efficiency ◽  
High Energy ◽  
Carnot Cycle ◽  
High Energy Conversion Efficiency ◽  
And Performance

Fuel cell is an electrochemical device, which can directly convert the chemical energy of fuel into electric energy, without heat process, not limited by Carnot cycle, high energy conversion efficiency, no noise and pollution.

Overview of Field Performance by UTC Fuel Cells’ Transportation Fuel-Cell Power Plants

2005 ◽  
Author(s):  
Praveen Narasimhamurthy ◽  
Zakiul Kabir
Keyword(s):  
Fuel Cells ◽  
Fuel Cell ◽  
Power Plants ◽  
Ambient Pressure ◽  
Polymer Electrolyte Membrane ◽  
Field Performance ◽  
Pem Fuel Cell ◽  
Low Noise ◽  
Transportation Fuel ◽  
Fuel Cell Stack

UTC Fuel Cells (UTCFC) over the last few years has partnered with leading automotive and bus companies and developed Polymer Electrolyte Membrane (PEM) fuel-cell power plants for various transportation applications, for instance, automotive, buses, and auxiliary power units (APUs). These units are deployed in various parts of the globe and have been gaining field experience under both real world and laboratory environments. The longest running UTC PEM fuel cell stack in a public transport bus has accumulated over 1350 operating hours and 400 start-stop cycles. The longest running APU fuel cell stack has accrued over 3000 operating hours with more than 3200 start-stop cycles. UTCFC PEM fuel-cell systems are low noise and demonstrate excellent steady state, cyclic, and transient capabilities. These near ambient pressure, PEMFC systems operate at high electrical efficiencies at both low and rated power conditions.

The Thermodynamic Evaluation and Optimization of Fuel Cell Systems

2006 ◽  
Vol 3 (2) ◽  
pp. 155-164 ◽  
Author(s):  
N. Woudstra ◽  
T. P. van der Stelt ◽  
K. Hemmes
Keyword(s):  
Heat Transfer ◽  
Fuel Cells ◽  
High Temperature ◽  
Fuel Cell ◽  
Energy Conversion ◽  
System Optimization ◽  
Fuel Conversion ◽  
Cell Systems ◽  
Electrochemical Conversion ◽  
Conversion Efficiencies

Energy conversion today is subject to high thermodynamic losses. About 50% to 90% of the exergy of primary fuels is lost during conversion into power or heat. The fast increasing world energy demand makes a further increase of conversion efficiencies inevitable. The substantial thermodynamic losses (exergy losses of 20% to 30%) of thermal fuel conversion will limit future improvements of power plant efficiencies. Electrochemical conversion of fuel enables fuel conversion with minimum losses. Various fuel cell systems have been investigated at the Delft University of Technology during the past 20 years. It appeared that exergy analyses can be very helpful in understanding the extent and causes of thermodynamic losses in fuel cell systems. More than 50% of the losses in high temperature fuel cell (molten carbonate fuel cell and solid oxide fuel cell) systems can be caused by heat transfer. Therefore system optimization must focus on reducing the need for heat transfer as well as improving the conditions for the unavoidable heat transfer. Various options for reducing the need for heat transfer are discussed in this paper. High temperature fuel cells, eventually integrated into gas turbine processes, can replace the combustion process in future power plants. High temperature fuel cells will be necessary to obtain conversion efficiencies up to 80% in the case of large scale electricity production in the future. The introduction of fuel cells is considered to be a first step in the integration of electrochemical conversion in future energy conversion systems.

Numerical Analysis of a Molten Carbonate Fuel Cell Stack in Emergency Scenarios

2020 ◽  
Vol 142 (9) ◽  
Author(s):  
Arkadiusz Szczęśniak ◽  
Jarosław Milewski ◽  
Łukasz Szabłowski ◽  
Olaf Dybiński ◽  
Kamil Futyma
Keyword(s):  
Fuel Cells ◽  
Fuel Cell ◽  
Numerical Analysis ◽  
High Accuracy ◽  
Molten Carbonate Fuel Cell ◽  
Molten Carbonate ◽  
Fuel Cell Stack ◽  
Power Load ◽  
Emergency Scenarios ◽  
Carbonate Fuel Cell

Abstract Molten carbonate fuel cells (MCFCs) offer several advantages that are attracting an increasingly intense research and development effort. Recent advances include improved materials and fabrication techniques as well as new designs, flow configurations, and applications. Several factors are holding back large-scale implementation of fuel cells, though, especially in distributed energy generation, a major one being their long response time to changing parameters. Alternative mathematical models of the molten carbonate fuel cell stack have been developed over the last decade. This study investigates a generic molten carbonate fuel cell stack with a nominal power output of 1 kWel. As daily, weekly, and monthly variations in the electrical power load are expected, there is a need to develop numerical tools to predict the unit’s performance with high accuracy. Hence, a fully physical dynamic model of an MCFC stack was developed and implemented in aspen hysys 10 modeling software to enable a predictive analysis of the dynamic response. The presented model exhibits high accuracy and accounts for thermal and electrochemical processes and parameters. The authors present a numerical analysis of an MCFC stack in emergency scenarios. Further functionality of the model, which was validated using real operational data, is discussed.

Component Failure Analysis From the U.S. Army ERDC-CERL Residential Proton Exchange Membrane Fuel Cells Demonstration

2006 ◽  
Author(s):  
Scott A. Kenner ◽  
Nicholas M. Josefik ◽  
Scott M. Lux ◽  
James L. Knight ◽  
Melissa K. White ◽  
...  
Keyword(s):  
Fuel Cells ◽  
Fuel Cell ◽  
Proton Exchange Membrane ◽  
Pem Fuel Cells ◽  
Proton Exchange ◽  
Fuel Cell Stack ◽  
The Mean ◽  
Exchange Membrane ◽  
Mean Time ◽  
The U.S

Background: The U.S. Army Engineer Research and Development Center, Construction Engineering Research Laboratory (ERDC-CERL) continues to manage The Department of Defense (DoD) Residential Proton Exchange Membrane (PEM) Fuel Cell Demonstration Project. This project was funded by the United States Congress for fiscal years 2001 through 2004. A fleet of 91 residential-scale PEM fuel cells, ranging in size from 1 to 5 kW, has been demonstrated at various U.S. DoD facilities around the world. Approach: The performance of the fuel cells has been monitored over a 12-month field demonstration period. A detailed analysis has been performed cataloging the component failures, investigating the mean time of the failures, and the mean time between failures. A discussion of the lifespan and failure modes of selected fuel cell components, based on component type, age, and usage will be provided. This analysis also addresses fuel cell stack life for both primary and back-up power systems. Several fuels were used throughout the demonstration, including natural gas, propane, and hydrogen. A distinction will be made on any variances in performance based on the input fuel stock. Summary: This analysis will provide an overview of the ERDC-CERL PEM demonstration fuel cell applications and the corresponding data from the field demonstrations. Special emphasis will be placed on the components, fuel cell stack life, and input fuel characteristics of the systems demonstrated.

scholarly journals Energy Conversion Analysis of a Novel Solar Thermochemical System Coupled With Fuel Cells

2015 ◽  
Author(s):  
Ian Vinck ◽  
Nesrin Ozalp
Keyword(s):  
Fuel Cells ◽  
Fuel Cell ◽  
Energy Conversion ◽  
Calorific Value ◽  
Electricity Production ◽  
Thermal Reactor ◽  
Hydrogen Fuel Cell ◽  
Combined System ◽  
Concentrated Solar Energy ◽  
Byproduct Formation

Fossil fuels have been the main supply of power generation for use in manufacturing, transportation, residential and commercial sectors. However, environmentally adverse effects of fossil fuel conversion systems combined with pending shortage raise major concerns. As a promising approach to tackle these challenges, this paper presents a novel energy conversion system comprising of a solar thermal reactor coupled with hydrogen fuel cell and carbon fuel cell for electricity generation. The system uses concentrated solar energy for high temperature heat which upgrades the calorific value of the feedstock by 8%. The paper describes the components and characteristics of the proposed concept and models the energy flow of this system. A comparison based on unit mass feedstock supply is made with conventional Brayton cycles for electricity production. The results show that the extent of acetylene byproduct conversion in the solar reactor is of crucial importance to ensure competitiveness. Depending on the fuel cells efficiency and even more on the extent of byproduct formation, the results show that the overall chemical-to-electrical efficiency of this combined system ranges from 35 to 58%.

Transient Analysis of Gas Distribution in the Anodic Flow Field in a Fuel Cell Stack

2013 ◽  
Author(s):  
Yasushi Ichikawa ◽  
Nobuyuki Oshima
Keyword(s):  
Fuel Cells ◽  
Fuel Cell ◽  
Flow Field ◽  
Polymer Electrolyte Fuel Cell ◽  
Gas Distribution ◽  
Fuel Cell Stack ◽  
Analysis Experiment ◽  
Hydrogen Supply ◽  
Cathodic Side ◽  
Anodic Side

In a polymer electrolyte fuel cell (PEFC), the catalyst degradation on cathodic side is one of the fatal problems caused by mal-distributed hydrogen supply into each channel on active area in a fuel cell, especially in a fuel cell stack for automotive fuel cell systems which consist of several hundreds of fuel cells stacked. For example, before getting the fuel cell system started-up, the gas in all the anodic flow passage including channels in each fuel cell is occupied by air instead of hydrogen due to cross leak from cathodic side to anodic side through the membrane employed as an electrolyte. In this situation, if hydrogen is supplied partially or unevenly between cells to start up the system, a concentration interface of air and hydrogen will be made within a fuel cell. This causes a state of local cell within a single fuel cell and the catalyst degradation (carbon corrosion or Pt dissolution) occurs. In this paper, to avoid this catalyst degradation, the gas distribution is investigated with pressurized hydrogen supply into channels located on the hundreds stacked fuel cells statically filled with air initially. A transient computational fluid analysis was applied to the flow fields of anodic side which consist of channels on fuel cells, both distributing and collecting manifold connected to the fuel cells under parameters: 1) number of stacked fuel cells (i.e. manifold length), 2) the rate of pressure rising (Pa/sec.) which makes the gas flow velocity. A gas analysis experiment was also carried out for a validation with mass spectrometer taking gas sample from several points along the gas channels on alternative fuel cells which are made of transparent acrylic resin. The results show that the uniform distribution in concentration between cells and its profile within the channels along the flow direction are strongly affected by flow field formed within the distributing manifold located upstream of stacked plates with channels.

Sign in / Sign up

Export Citation Format

Share Document