bluuebunny/crossref_metadata_2025_split huggingface dataset:
System design and applications
Authors: Strasser K. 
Published: December 2010

Abstract

Over a period of 20 years, starting from 1967, research and developmental work on alkaline fuel cells was conducted at Siemens with the aim of increasing power density of the cell, improving long‐term behavior, cell function and design, decreasing cost and gather experience by testing laboratory models and prototypes. Based on Raney nickel as the anode catalyst and doped silver as the cathode catalyst, a cell voltage of 0.7 V at a current density of 400 mA cm
−2
can be reached. Cell operating conditions are 80 °C and 2 bar reactant pressures (absolute H
2
and O
2
). The cell is characterized by the dimensions 240 × 245 cm
2
and an active area of 340 cm
2
. Reaction water is removed from the cell by an electrolyte circulation. It is evaporated and condensed in a slit‐like regenerator by removing the waste heat. The fuel cell stack, electrolyte regenerator and electromechanical control unit form a compact module block, which yields power ratios of approximately 10 kg kW
−1
and 8 l kW
−1
, respectively. Modules with 35, 60 and 70 cells and a power output of 1–7 kW have been realized and also power plants consisting of more modules with a power output of 20–100 kW and a voltage of more than 200 V. A 100 kW prototype fuel cell power plant was tested successfully as part of an air independent propulsion system in the U205 submarine of the German Navy from August 1988 to March 1989. But in spite of the positive results the polymer electrolyte fuel cell was preferred because of its better long‐term behavior and higher power density. There is no doubt that the relatively high production cost will limit the application in special areas such as submarines in the short term.
A comparison between the alkaline fuel cell (
AFC
) and the polymer electrolyte membrane (
PEM
) fuel cell
Authors: Kordesch K. , Cifrain M. 
Published: December 2010

Abstract

This comparison discusses the electrode and system design differences between acid fuel cells with an immobilized electrolyte (e.g., contained in a matrix, in a gelled layer or in a membrane) and alkaline systems, mainly using a free flowing electrolyte. The inherent electrochemical and technological advantages and disadvantages are pointed out. The likely reasons for the historically often changed selection of certain fuel cell types for various applications are presented, relating the choices to opportunities and technical circumstances. These choices are by no means final and are still open. However, they depend not so much on technical or electrochemical problems and solutions, but on available materials, manufacturing feasibilities and in particular on the cost of the total system to be used for a specific purpose. A modern example is the planned use of polymer electrolyte membrane (PEM) fuel cells for electric vehicles. These membrane fuel cells are supposed to replace a combustion engine which costs $50–100 kW
−1
power output, but do require at the present time an investment of thousands of dollars per kilowatt. Why did so many proponents chose this system and/or this application? Can other systems do better? This comparison suggests alternatives.
Stack materials and stack design
Authors: Breault R. D. 
Published: December 2010

Abstract
The 35 year history of phosphoric acid fuel cell stack development at United Technologies Corporation is traced through three generations of power plants that culminated in the 200 kW ™PC‐25 fuel cell power plant. The evolution of stack materials and designs for the electrolyte retaining matrix, electrode substrate, electrolyte reservoir plates, separator plates and coolers are described. Electrolyte management issues relating to water management, electrolyte distribution between cell components, freeze prevention, acid evaporation, and acid transfer by electrochemical pumping are reviewed. Corrosion issues relating to separator plates, anode corrosion, edge seal corrosion and operation at low power levels are discussed. Thoughts on potential improvements to reduce the cost and double the life of the phosphoric acid fuel cell stack are presented.
Catalyst studies and coating technologies
Authors: Landsman D. A. , Luczak F. J. 
Published: December 2010

AbstractAn account is given of the development of electrocatalysts for the phosphoric acid (phosphoric acid) fuel cell starting from unsupported platinum black and ending with carbon‐supported platinum alloys. The incentive for this work was the need to reduce the cost of the phosphoric acid fuel cell by reducing the amount of platinum it contained while simultaneously raising its performance. Equally important was the concurrent effort aimed at optimizing the structure of the polytetrafluoroethylene (PTFE)‐bonded, gas‐diffusion electrodes so that the noble metal catalysts were used as effectively as possible. Methods to control the structure of the catalyst layer were devised based on studies of the way in which aqueous dispersions of the supported catalyst and PTFE interact. Procedures used to prepare electrodes in the laboratory were modified and scaled up for production purposes. A novel process for depositing catalyst layers on electrode substrates was developed and several different coating technologies were evaluated for applying PTFE‐bonded, silicon carbide, electrolyte‐retaining matrices to the electrodes. Some operating conditions that can have an adverse affect on the life of the electrodes are considered. Most of the work described here originated in the laboratories and workshops of International Fuel Cells — a unit of United Technologies Corporation — and culminated in the PC25 phosphoric acid fuel cell power plant.
Experience with 200
k
W
PC
25 fuel cell power plant
Authors: King J. M. , McDonald B. 
Published: December 2010

Abstract
The 200 kW PC25 fuel cell power plant has demonstrated the intrinsic characteristics of fuel cells: high electrical and overall efficiency over a wide range of loads, rapid transient response, quiet operation and low emission of controlled pollutants. The power plants are designed to an industry standard and certified by an independent agency. Permitting approval for power plant installation has been achieved with minimal problems.
The standard production power plant has been installed in a wide range of climates, operated on natural gas with compositions delivered in over 100 cities and 19 countries, and connected to many different electrical systems. A number of installations are fueled with waste gas from the anaerobic digestion process in waste water treatment plants. It has been applied to a variety of buildings in a number of electrical and thermal configurations. By the first half of 2002, the more than 200 power plants in the installed fleet had accumulated five million operating hours. Routine maintenance interval while the power plant is operating has reached six months. Individual units have exceeded 40 000 operating hours without overhaul and power plant availability in the high 90s has been demonstrated.
The primary factors limiting broader application of the power plants are high power plant cost and a lack of knowledge of the fuel cell characteristics and benefits.
Stack material and stack design
Authors: Mugikura Y. 
Published: December 2010

AbstractMCFC power plants have been developed in many countries. The efficiencies of MCFC plants are expected to be higher than those of conventional power plants, such as advanced combined cycle power plants. The MCFC stack is the main element and the key technology in MCFC systems is to achieve both high efficiency and long lifetime. Molten carbonate is used as the electrolyte and is known to be a significantly reactive material. The high reactivity of the molten carbonate provides excellent cell reaction rates but accelerates corrosion of cell components. Suitable stack designs and materials to prevent corrosion of cell components are the main focus of the following chapter. Different materials for the anode, cathode, matrix and separator plate are considered. Performance and lifetime data of stack manufacture are given. Internal and external reforming is compared. Different concepts for gas manifolds and gas flow types are discussed. The status of stack technology is given. Furthermore, optimization of operating conditions as another approach to fulfilling the requirements concerning high efficiency over a long time is discussed.
Low temperature electrolytes and catalysts
Authors: Yamamoto O. 
Published: December 2010

Abstract
Fluoride‐type oxide ion conductors are reviewed in terms of electrical conductivity and oxide ion transport number as the electrolyte in low‐temperature solid oxide fuel cells. In particular, zirconia‐based systems and ceria‐based systems are introduced. Electrode materials with high oxygen reduction catalytic activity at low temperatures are introduced, and also anode materials for the reduction of hydrocarbons at low temperatures are discussed.
MEA
/cell preparation methods:
J
apan/
A
sia
Authors: Suzuki M. 
Published: December 2010

Abstract

Many cell designs and manufacturing technology of membrane and electrode assembly (MEA) have been tried in Japanese solid oxide fuel cell (SOFC) developments. Since the development of SOFC stacks is related very closely with the manufacturing process and cell design, the representative MEA/cell preparation methods are described below as the tubular type and the planer type. In the early 1990s, concerning the tubular cell, it was generally considered that cost reduction was difficult, although the reliability was excellent. At that time, Japanese manufactures started developing the tubular cell by the sintering method in order to reduce cell preparation costs. The difficulty of fabricating tubular cells by the sintering method is that the dense electrolyte and interconnect film must be deposited on the porous substrate. Two kinds of slurry coating methods, dipping and printing, were applied. As of 2002, the low cost tubular cell manufacturing technology is at the 10 kW class module stage. Concerning the planer type, 15 kW modules were manufactured and tested in 2001. In this development, MEAs are fabricated with an embossed self‐supporting yttria‐stabilized zirconia (YSZ) electrolyte, Ni/YSZ anode and a doped LaMnO
3
cathode. The dimpled MEA structure has two advantages for cost reduction. One is the increase of the active surface area and the other is the adaptable flat (ribbless) separators. An anode supported YSZ electrolyte planer cell and a doped LaGaO
3
electrolyte cell are also under development in Japan.
Novel electrolytes operating at 400‐600 °C
Authors: Ishihara T. 
Published: December 2010

AbstractSome high oxide ion and proton conductors that can be used as electrolytes operating at temperatures less than 600 °C are reviewed. In particular, the oxide ion conductivity of the perovskite oxide of LaGaO3is discussed and applications of the LaGaO3‐based oxide as the electrolyte of solid oxide fuel cells (SOFCs) are introduced. Since the LaGaO3‐based oxide is highly stable over a widerange, the open circuit potential of the fuel cell is close to the theoretical one and a high power density of a few 100 mW cm−2has been achieved at 873 K in spite of the 0.5 mm thick La0.8Sr0.2Ga0.8Mg0.125Co0.085O3(LSGMC) electrolyte. A high power density has also been exhibited in the cell using a larger sized LSGMC electrolyte. LSGMC has a great potential as an electrolyte of fuel cells operating at intermediate temperatures. On the other hand, the CeO2‐based oxide is also promising as an electrolyte of intermediate temperature SOFCs because oxide ion transport number increased with decreasing temperature. A new family of oxide ion conductors with a noncubic structure has recently been reported and the ion conductivity in these oxides is also discussed. On the other hand, proton‐conducting oxides are also studied as electrolytes of intermediate temperature SOFCs and the applications of some perovskite proton‐conducting oxides as electrolytes of intermediate temperature fuel cell are also mentioned.
Alkaline methanol/air power devices
Authors: Koscher G. A. , Kordesch K. 
Published: December 2010

AbstractMethanol is a promising fuel for power devices like fuel cells because it has a high theoretical capacity per volume and weight, it is relatively easy to handle and it is easy to store. Many investigations into the alkaline methanol fuel cell system were made in the 1960s and 1970s. This chapter provides a brief summary of this research and tries to explain why interest in these systems has declined.
Portable direct methanol fuel cell systems
Authors: Narayanan S. R. , Valdez T. I. 
Published: December 2010

Abstract
The simplicity of the direct electrooxidation of methanol in a polymer electrolyte membrane fuel cell and the technological advances achieved in performance and efficiency in the last 10 years has spurred the development of direct methanol fuel cell (DMFC)‐based portable power systems in the power range of 0.1–150 W. Most of the system demonstrations to date have focused on proving the feasibility of novel stack designs, membrane types, integrated system configurations, and miniaturization concepts. This article includes discussion of the specific power and power density requirements for various portable system applications, the status of stack technology, progress in the implementation of balance‐of‐plant designs, and a summary of the characteristics of various DMFC portable power source demonstrations. Compact monopolar and bipolar designs are demonstrated at various power levels. Integrated systems at the 25–150 W level have demonstrated functionality for multi‐purpose power source applications for the military and commercial area, although these demonstration present substantial scope for weight and volume improvements. Efforts in the power range of 0.1–15 W have focused on size and mass, as these are premium requirements for the small portable consumer electronics market. Recent demonstrations relate to lightweight stack configurations while closed loop systems with water recovery and thermal management are at best in the initial phases of demonstration.
Small‐sizePEMsystems for special applications
Authors: Büchi F. N. 
Published: December 2010

AbstractThe trend towards more mobility in many aspects of life in 21stcentury society creates a need for mobile power sources in situations and areas where no grid power is available. Today mobile power in the medium power range (several 10 W to several kW) is mostly provided by either batteries or IC engine‐driven generators. However competing technologies such as low temperature fuel cells are evolving. This article describes the fuel requirements, advantages, and properties, examples of systems and applications of polymer electrolyte fuel cells for these special applications.
General motors/
OPEL
Fuel cell activities — driving towards a successful future
Authors: Rodrigues A. , Fronk M. , McCormick B. 
Published: December 2010

Abstract
General Motors (GM) is the world's largest automobile maker. Over the years, GM has supported fuel cell activities as an alternative propulsion system to the internal combustion engine. In 1966, GM demonstrated the first driveable fuel cell vehicle. Since then, with continuous research and development and system optimization, various successful fuel cell systems have been demonstrated. GM has progressively made improvements with increases in power densities in both their fuel cell stacks and fuel cell processors, as well as a focus in understanding and developing systems. To aggressively drive fuel cell applications to commercialization, GM has partnered with a conglomerate of companies, each bringing its unique contribution to the commercialization plan. Maintaining several options and understanding both the near‐term and long‐term needs of the market, GM is pursuing hydrogen‐fueled and gasoline‐reformate‐fueled fuel cell systems in both the automotive and nonautomotive application markets.
H
2
/
O
2
‐
PEM
‐fuel cell module for an air independent propulsion system in a submarine
Authors: Strasser K. 
Published: December 2010

Abstract
Since the end of the 1960s the German Navy has been looking for an innovative, nonnuclear propulsion technology, which allows significant increase in the submerged mission duration of submarines and simultaneously low heat and low noise signature. One of the technologies that seems to be able to fulfill such requirements is the fuel cell. During the 1980s, by order of a German consortium of different industrial companies headed by the shipyard Howaldtswerke Deutsche Werft AG (HDW) an alkaline fuel cell power plant with a power output of 100 kW, based on a 6 kW FC module of the Siemens alkaline fuel cell technology, was installed on Submarine U1 of the German Navy and was tested by the Navy from August 1988 to March 1989, gathering knowledge and experience from successful tests of this new FC system. In parallel by order of the German Federal Ministry of Defence, Siemens had to develop a 30–50 kW fuel cell module, based on the polymer electrolyte membrane fuel cell (PEMFC) as a power source for an air independent submarine propulsion system. Started at the beginning of the 1980s, the development was finished in 1996. Two FC module prototypes had achieved all the requirements of the customer's specification regarding function, power output, shock, stray field, inclination, electromagnetic compatibility, noise, dimensions, weight and technical safety. By testing the dynamic and static load behavior, the outstanding properties of the FC modules were confirmed. The FC module is being used as part of the FC power plant of an air independent propulsion system on the new German Submarine Class 212 worldwide for the first time. Further developments aim to enlarge the FC module power and voltage (120–200 kW; 208–300 V) to decrease the cost. The PEMFC technology, now available at Siemens, has been further used to investigate different propulsion systems (electric buses; forklift trucks) and power supplies.
Space‐shuttle fuel cell
Authors: Wagner H. A. 
Published: December 2010

Abstract
The space shuttle uses three alkaline fuel cells to satisfy all electrical power requirements from pre‐launch to post‐landing. The space shuttle operates on all three fuel cells in parallel but can operate safely on two fuel cells if there is a problem with one of the fuel cells. The alkaline fuel recombines hydrogen and oxygen gases to form water and create electricity. The product water is provided to the astronauts for use as their drinking water. The current fuel cells operate for up to 2600 h before requiring an overhaul. The long life alkaline fuel cell is being developed to extend the useful life out to 5000 h between overhauls. A secondary goal is to demonstrate the ability to operate the space shuttle on a single fuel cell during entry and landing.
PEMFCfuel cell systems
Authors: Garche J. , Jörissen L. 
Published: December 2010

AbstractThe stationary applications of the proton exchange membrane (PEM) fuel cell are described. The applications are divided into the combined heat and power generation for household energy supply (<10 kWel) and larger units (50–250 kW) for district energy supply, secure energy supply, and premium power supply. However, this chapter focuses on residential applications. The technical aspects of the whole fuel cell system are discussed with emphasis on this application, with its subsystems as the gas processing or the heat and water management system, together with the best operating conditions of the fuel cell and the questions of economy and ecology. The developers of PEM fuel cell systems in North America, Europe, and Japan are stated and the competing technologies based on Carnot processes are also shown. Finally the market expectations for the residential PEM fuel cell systems are discussed.
MCFCfuel cell systems
Authors: Bischoff M. , Farooque M. , Satou S. , Torazza A. 
Published: December 2010

AbstractFuel cell systems are able to convert chemical energy directly into electrical energy and, therefore, they are in principle able to achieve much higher electrical efficiencies than conventional thermal systems. Fuel cells also have environmental advantages: they emit negligible amounts of NOx, SOxand particulates although the latter two reflect a need for fuel cells utilizing fuel gas which is nearly sulfur‐ and particulate‐free. The most important characteristic of MCFCs is that they are fed with fuel gas containing hydrogen and carbon monoxide. The obvious method is to supply this fuel gas through thermal reforming of natural gas or through gasification of coal. Therefore, the total MCFC energy conversion system is considerably more than just the stack itself.
SOFCfuel cell systems
Authors: Veyo S. E. , Fukuda S. , Shockling L. A. , Lundberg W. L. 
Published: December 2010

AbstractSiemens Westinghouse Power Corporation is developing the tubular solid oxide fuel cell and has applied the solid oxide fuel cell (SOFC) in a successfully concluded proof‐of‐concept field test of a grid and district heating system connected atmospheric pressure 100 kWe power system that has operated for over 16 000 h without noticeable performance degradation. A 250 kWe power system of similar design will be introduced commercially in 2004. A hybrid power system consisting of a pressurized SOFC coupled hydraulically to a micro gas turbine has been constructed as a proof‐of‐concept experiment. Although testing has not yet been concluded, the hybrid system has operated showing promising performance. SOFC systems operate with characteristically high electrical efficiency—typically 50% (net a.c./LHV) can be approached with atmospheric pressure systems and 60% with simple pressurized SOFC/micro gas turbine hybrid cycle systems. More complex hybrid cycles are projected to approach 70% efficiency. Basics of the Siemens Westinghouse tubular SOFC technology are discussed and three cycle concepts are reviewed. The status of current and planned technology demonstration projects is also discussed and the results of several recent conceptual design studies that explore the potential of the SOFC for larger capacity power systems are summarized.
Life‐cycle analysis of fuel cell system components
Authors: Pehnt M. 
Published: December 2010

AbstractDue to the efficient and (almost) zero emission operation of fuel cells, they are particularly attractive for application in the transportation sector and in stationary power conversion. For an environmental evaluation of new technologies, however, an investigation of the complete life‐cycle is necessary to ensure that no environmental aspect is neglected. In this “cradle‐to‐grave approach”, not only the use phase, but also the supply of the fuel and the production and disposal/recycling of the vehicle or power plant have to be considered. The appropriate instrument for this task is life‐cycle assessment (LCA).This chapter presents LCAs of fuel cells in mobile and stationary applications with different fuel options and compares them to conventional power train or plant options focusing on different environmental aspects, such as use of resources, global warming, acidification and emission of carcinogenic substances. For this purpose, future developments of the fuel cell competitors, e.g., internal combustion engines, gas turbines, combined cycle plants, etc., have to be taken into account as well.In vehicle applications, special focus is paid to the question of the best fuel, which is of considerable importance for the performance of fuel cell vehicles. The production of the required materials, e.g., catalyst materials and system components are also described and assessed.In stationary systems, cogeneration applications using low and high‐temperature fuel cells are investigated thoroughly.