• Wejrzanowski, Tomasz
• Milewski, Jarosław
• Ćwieka, Karol
• Ibrahim, Samih Haj

Abstract

High temperature fuel cells, including molten carbonate fuel cell (MCFC) and solid oxide fuel cell (SOFC), are electrochemical devices used for highly efficient conversion of gaseous fuels into electricity. The fuel cell operation efficiency and lifetime are limited by several factors, mainly related to chemical composition and microstructure of electrode materials.The comprehensive design of high temperature fuel cell (HTFC) materials requires the optimization of both: chemical composition and microstructure. The chemical composition greatly determines corrosion resistance and catalytic activity of the electrode surface, while the microstructure provides pathways for sufficient mass-transport of gaseous reactants, interaction/exchange of gas molecules, as well as transport of electrons and ions. Many studies have been devoted to proposing various material solutions for HTFC incorporating complex chemical compositions, while little is known about the microstructural effects on the fuel cell performance. A better understanding of these phenomena by the application of modern methods involving fabrication, characterization and numerical modeling of materials leads to the improvement of fuel cell performance and durability.Within these studies, a deeper insight into the understanding of the influence of porosity, pore size distribution, specific surface area, and other microstructure parameters on the performance of molten carbonate fuel cell is presented by the complementary application of fabrication, characterization and modeling techniques. The results of these investigations into MCFC show that the appropriate design of the microstructural features of the cathode might even double the power density of the cell. Therefore, open-porous microstructure of MCFC cathode with multi modal pore size distribution is beneficial. It strongly determines the total length of the triple phase boundary (TPB) within a material which is an important factor to be optimized for increasing the efficiency of the complex electrode reactions.To differentiate the porosity and the pore size distribution, several nickel-based electrodes were manufactured by tape casting technique with various porogen contents

Topics

• porous
• density
• impedance spectroscopy
• pore
• surface
• nickel
• corrosion
• phase
• chemical composition
• casting
• porosity
• durability
• phase boundary