Characterisation of Solid Oxide Fuel Cell Electrode Microstructures in Three Dimensions PDF Download

Author: Paul R. Shearing
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Author: Shenjia Zhang
Publisher:
ISBN:
Category : Fuel cells
Languages : en
Pages :

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Three-phase porous composites containing electrolyte (ionic conductor), electronic conductor, and porosity phases are frequently used for solid oxide fuel cell (SOFC) electrodes. Performance of such electrodes is microstructure sensitive. Topological connectivity of the microstructural phases and total length of triple phase boundaries are the key microstructural parameters that affect the electrode performance. These microstructural attributes in turn depend on numerous process parameters including relative proportion, mean sizes, size distributions, and morphologies of the electrolyte and electronic conductor particles in the powder mix used for fabrication of the composites. Therefore, improvement of the performance of SOFC composite electrodes via microstructural engineering is a complex multivariate problem that requires considerable input from microstructure modeling and simulations. This dissertation presents a new approach for geometric modeling and simulation of three-dimensional (3D) microstructure of three-phase porous composites for SOFC electrodes and provides electrode performance optimization guidelines based on the parametric studies on the effects of processing parameters on the total length and topological connectivity of the triple phase boundaries. The model yields an equation for total triple phase boundary length per unit volume (LTPB) that explicitly captures the dependence of LTPB on relative proportion of electrolyte and electronic conductor phases; volume fraction of porosity; and mean size, coefficient of variation, and skewness of electrolyte and electronic conductor particle populations in the initial powder mix. The equation is applicable to electrolyte and electronic conductor particles of any convex shapes and size distributions. The model is validated using experimental measurements performed in this research as well as the measurements performed by other researchers. Computer simulations of 3D composite electrode microstructures have been performed to further validate the microstructure model and to study topological connectivity of the triple phase boundaries in 3D microstructural space. A detailed parametric analysis reveals that (1) non-equiaxed plate-like, flake-like, and needle-like electrolyte and electronic conductor particle shapes can yield substantially higher LTPB; (2) mono-sized electrolyte and electronic conductor powders lead to higher LTPB as compared to the powders having size distributions with large coefficients of variation; (3) LTPB is inversely proportional to the mean sizes of electrolyte and electronic conductor particles; (4) a high value of LTPB is obtained at the lowest porosity volume fraction that permits sufficient connectivity of the pores for gas permeability; and (5) LTPB is not sensitive to the relative proportion of electrolyte and electronic conductor phases in the composition regime of interest in composite electrode applications.

Author: Joos, Jochen
Publisher: KIT Scientific Publishing
ISBN: 3731506254
Category : Technology (General)
Languages : en
Pages : 246

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This work deals with microstructural characterisation, modelling and simulation of SOFC electrodes with the goal of optimizing the electrode microstructures. Methods for a detailed electrode analysis based on focused ion beam (FIB) tomography are presented. A 3D FEM model able to perform simulations of LSCF cathodes based on 3D tomography data is shown. A model generating realistic, yet synthetic microstructures is presented that enables the optimization of microstructural characteristics.

Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Author: Jochen Joos
Publisher:
ISBN: 9781013279935
Category : Science
Languages : en
Pages : 236

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Book Description
This work deals with microstructural characterisation, modelling and simulation of SOFC electrodes with the goal of optimizing the electrode microstructures. Methods for a detailed electrode analysis based on focused ion beam (FIB) tomography are presented. A 3D FEM model able to perform simulations of LSCF cathodes based on 3D tomography data is shown. A model generating realistic, yet synthetic microstructures is presented that enables the optimization of microstructural characteristics. This work was published by Saint Philip Street Press pursuant to a Creative Commons license permitting commercial use. All rights not granted by the work's license are retained by the author or authors.

Author: Meng Ni
Publisher: Royal Society of Chemistry
ISBN: 1849737770
Category : Science
Languages : en
Pages : 539

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Solid oxide fuel cells (SOFCs) are promising electrochemical power generation devices that can convert chemical energy of a fuel into electricity in an efficient, environmental-friendly, and quiet manner. Due to their high operating temperature, SOFCs feature fuel flexibility as internal reforming of hydrocarbon fuels and ammonia thermal cracking can be realized in SOFC anode. This book presents an overview of the SOFC technology with a focus on the recent developments in new technologies and new ideas for addressing the key issues of SOFC development. This book first introduces the fundamental principles of SOFCs and compares SOFC technology with conventional heat engines as well as low temperature fuel cells. Then the latest developments in SOFC R&D are reviewed and future directions are discussed. Key issues related to SOFC performance improvement, long-term stability, mathematical modelling, as well as system integration/control are addressed, including material development, infiltration technique for nano-structured electrode fabrication, focused ion beam – scanning electron microscopy (FIB-SEM) technique for microstructure reconstruction, the Lattice Boltzmann Method (LBM) simulation at pore scale, multi-scale modelling, SOFC integration with buildings and other cycles for stationary applications.

Author: Andrea Alberto Mammoli
Publisher: WIT Press
ISBN: 1845645383
Category : Technology & Engineering
Languages : en
Pages : 433

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Until recently, engineering materials could be characterized successfully using relatively simple testing procedures. However, advanced materials technology has led to the development of materials with complex meso-, micro- and nano-structures that can no longer be characterised with simple testing procedures. Materials modelling and characterisation have become ever more closely intertwined. Characterisation, in essence, connects the abstract material model with the real-world behaviour of the material in question. Characterisation of complex materials often requires a combination of experimental and computational techniques. This book contains papers to be presented at the Fifth International Conference, convened to facilitate the sharing of recent work between researchers who use computational methods, those who perform experiments, and those who do both, in all areas of materials characterisation. The papers cover such topics as: Advances in composites; Thermal analysis; Nano-materials; Damage mechanics; Computational models and experiments; Mechanical characterisation and testing; Nano-composites; Energy materials; Chemo-mechanical problems; Innovative experiments; Recycled materials; and Corrosion problems.

Author: S. C. Singhal
Publisher: The Electrochemical Society
ISBN: 156677862X
Category : Science
Languages : en
Pages : 3058

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This issue of ECS Transactions contains papers from the Twelfth International Symposium on Solid Oxide Fuel Cells (SOFC-XII),a continuing biennial series of symposia. The papers deal with materials for cell components and fabrication methods for components and complete cells. Also contained are papers on cell electrochemical performance and its modelling, stacks and systems, and prototype testing of SOFC demonstration units for different applications.

Author: Kevin Kendall
Publisher: Elsevier
ISBN: 0124104835
Category : Technology & Engineering
Languages : en
Pages : 522

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Book Description
High-temperature Solid Oxide Fuel Cells, Second Edition, explores the growing interest in fuel cells as a sustainable source of energy. The text brings the topic of green energy front and center, illustrating the need for new books that provide comprehensive and practical information on specific types of fuel cells and their applications. This landmark volume on solid oxide fuel cells contains contributions from experts of international repute, and provides a single source of the latest knowledge on this topic. A single source for all the latest information on solid oxide fuel cells and their applications Illustrates the need for new, more comprehensive books and study on the topic Explores the growing interest in fuel cells as viable, sustainable sources of energy

Author: Moises R. Cesario
Publisher: Frontiers in Ceramic Science
ISBN: 9781681084329
Category : Technology & Engineering
Languages : en
Pages : 184

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Book Description
Solid Oxide Fuel Cells (SOFCs) have received great attention among researchers in the past few decades due to their high electrochemical energy conversion efficiency, environmental friendliness, fuel flexibility and wide range of applications. This volume is a contribution from renowned researchers in the scientific community interested in functional materials for SOFCs. Chapters in this volume emphasize the processing, microstructure and performance of electrolyte and electrode materials. Contributors review the main chemical and physical routes used to prepare ceramic/composite materials, and explain a variety of manufacturing techniques for electrode and electrolyte production and characterization. Readers will also find information about both symmetrical and single fuel cells. The book is a useful reference for students and professionals involved in SOFC research and development.