High-temperature Solid Oxide Fuel Cells: Fundamentals, Design and Applications (eBook)

Front Cover 1
High Temperature Solid Oxide Fuel Cells: Fundamentals, Design and Applications 4
Copyright Page 5
Contents 6
List of Contributors 12
Preface 16
Chapter 1. Introduction to SOFCs 18
1.1 Background 18
1.2 Historical Summary 19
1.3 Zirconia Sensors for Oxygen Measurement 21
1.4 Zirconia Availability and Production 22
1.5 High-Quality Electrolyte Fabrication Processes 24
1.6 Electrode Materials and Reactions 25
1.7 Interconnection for Electrically Connecting the Cells 28
1.8 Cell and Stack Designs 29
1.9 SOFC Power Generation Systems 31
1.10 Fuel Considerations 32
1.11 Competition and Combination with Heat Engines 34
1.12 Application Areas and Relation to Polymer Electrolyte Fuel Cells 35
1.13 SOFC-Related Publications 36
References 36
Chapter 2. History 40
2.1 The Path to the First Solid Electrolyte Gas Cells 40
2.2 From Solid Electrolyte Gas Cells to Solid Oxide Fuel Cells 43
2.3 First Detailed Investigations of Solid Oxide Fuel Cells 46
2.4 Progress in the 1960s 49
2.5 On the Path to Practical Solid Oxide Fuel Cells 57
References 61
Chapter 3. Thermodynamics 70
3.1 Introduction 70
3.2 The Ideal Reversible SOFC 73
3.3. Voltage Losses by Ohmic Resistance and by Mixing Effects by Fuel Utilisation 79
3.4 Thermodynamic Definition of a Fuel Cell Producing Electricity and Heat 83
3.5 Thermodynamic Theory of SOFC Hybrid Systems 86
3.6 Design Principles of SOFC Hybrid Systems 94
3.7 Summary 97
References 98
Chapter 4. Electrolytes 100
4.1 Introduction 100
4.2 Fluorite-Structured Electrolytes 100
4.3 Zirconia-Based Oxide Ion Conductors 106
4.4 Ceria-Based Oxide Ion Conductors 109
4.5 Fabrication of ZrO2- and CeO2-Based Electrolyte Films 111
4.6 Perovskite-Structured Electrolytes 113
4.7 Oxides with Other Structures 123
4.8 Proton-Conducting Oxides 127
4.9 Summary 129
References 129
Chapter 5. Cathodes 136
5.1 Introduction 136
5.2 Physical and Physicochemical Properties of Perovskite Cathode Materials 137
5.3 Reactivity of Perovskite Cathodes with ZrO2 147
5.4 Compatibility of Perovskite Cathodes with Interconnects 155
5.5 Fabrication of Cathodes 159
5.6 Summary 160
References 160
Chapter 6. Anodes 166
6.1 Introduction 166
6.2 Requirements for an Anode 167
6.3 Choice of Cermet Anode Components 168
6.4 Cermet Fabrication 170
6.5 Anode Behaviour Under Steady-State Conditions 173
6.6 Anode Behaviour Under Transients Near Equilibrium 175
6.7 Behaviour of Anodes Under Current Loading 177
6.8 Operation of Anodes with Fuels other than Hydrogen 181
6.9 Anodes for Direct Oxidation of Hydrocarbons 182
6.10 Summary 185
References 186
Chapter 7. Interconnects 190
7.1 Introduction 190
7.2 Ceramic Interconnects (Lanthanum and Yttrium Chromites) 191
7.3 Metallic Interconnects 198
7.4 Protective Coatings and Contact Materials for Metallic Interconnects 204
7.5 Summary 206
References 207
Chapter 8. Cell and Stack Designs 214
8.1 Introduction 214
8.2 Planar SOFC Design 214
8.3 Tubular SOFC Design 227
8.4 Microtubular SOFC Design 236
8.5 Summary 241
References 242
Chapter 9. Electrode Polarisations 246
9.1 Introduction 247
9.2 Ohmic Polarisation 249
9.3 Concentration Polarisation 250
9.4 Activation Polarisation 254
9.5 Measurement of Polarisation (By Electrochemical Impedance Spectroscopy) 268
9.6 Summary 274
References 274
Chapter 10. Testing of Electrodes, Cells and Short Stacks 278
10.1 Introduction 278
10.2 Testing Electrodes 279
10.3 Testing Cells and 'Short' Stacks 284
10.4 Area-Specific Resistance (ASR) 289
10.5 Comparison of Test Results on Electrodes and on Cells 294
10.6 The Problem of Gas Leakage in Cell Testing 300
10.7 Summary 303
References 303
Chapter 11. Cell, Stack and System Modelling 308
11.1 Introduction 310
11.2 Flow and Thermal Models 311
11.3 Continuum-Level Electrochemistry Model 316
11.4 Chemical Reactions and Rate Equations 320
11.5 Cell- and Stack-Level Modelling 325
11.6 System-Level Modelling 331
11.7 Thermomechanical Model 332
11.8 Electrochemical Models at the Electrode Level 335
11.9 Molecular-LeveI Models 342
11.10 Summary 343
References 344
Chapter 12. Fuels and Fuel Processing 350
12.1 Introduction 350
12.2 Range of Fuels 352
12.3 Direct and Indirect Internal Reforming 355
12.4 Reformation of Hydrocarbons by Steam, CO2 and Partial Oxidation 359
12.5 Direct Electrocatalytic Oxidation of Hydrocarbons 363
12.6 Carbon Deposition 364
12.7 Sulphur Tolerance and Removal 368
12.8 Anode Materials in the Context of Fuel Processing 369
12.9 Using Renewable Fuels in SOFCs 371
12.10 Summary 372
References 373
Chapter 13. Systems and Applications 380
13.1 Introduction 380
13.2 Trends in the Energy Markets and SOFC Applicability 382
13.3 Competing Power Generation Systems and SOFC Applications 384
13.4 SOFC System Designs and Performance 387
13.5 SOFC System Demonstrations 397
13.6 Summary 405
References 406
Index 410