New Cathode Materials for Molten Carbonate Fuel Cells

Abstract

Development of alternative cathode materials, has been a main strategy for solving the cathode dissolution problem of the Molten Carbonate Fuel Cell (MCFC). Ternary compositions of LiFeO2, LiCoO2 and NiO are expected to combine some desirable properties of each component. Preliminary studies on LiFeO2‐LiCoO2‐NiO ternary compositions have shown promising characteristics for the MCFC cathode application. The aim of the present work was to develop these materials further by exploring the ternary system. It was carried out by investigating electronic conductivity and microstructure of the ternary materials and evaluating their electrochemical performance in a laboratory‐scale fuel cell. Ternary materials of two sub‐systems were investigated and the study reveals the ability of improving electrical conductivity of these ternary compositions by controlling the LiCoO2 content. The appropriate dual pore structure for a proper cathode operation could also be achieved on sintered cathodes by introducing plastic poreformers in the cathode preparation process. Electrochemical performance study of selected cathodes in the laboratory fuel cell showed promising results. The cathode prepared with 20 mole% LiCoO2 in the ternary sub‐system with LiFeO2:NiO = 25:75, resulted in an iR‐corrected polarization of 62 mV and an iR‐drop of 46 mV at a current density of 160 mAcm–2 at 650 °C.

Liquid-Feed Flame Spray Pyrolysis as a Method of Producing Mixed-Metal Oxide Nanopowders of Potential Interest as Catalytic Materials. Nanopowders along the NiO−Al2O3 Tie Line Including (NiO)0.22(Al2O3)0.78, a New Inverse Spinel Composition

“…Numerous single and mixed-metal oxides, both pure and in supported forms, play important roles in commercial catalytic processes ranging from petroleum refining to environmental control, processing fine chemicals, andcomponents in fuel cells. Of the many catalyst systems studied extensively, nickel spinel and alumina supported nickel catalysts are among those that have widespread commercial value in catalytic applications ranging from methane/steam and methanol reforming − to hydrocarbon cracking, dehydrogenation, hydrodesulfurization, and hydrodenitrogenation. − Most recently, nickel spinel has received attention as an electrode material in high-temperature carbonate based fuel cells. , …”

Characterization in MCFC conditions of high-temperature, potentiostatically deposited Co-based thin films on NiO cathode

“…Several materials have been studied as other components for the MCFC cathode. The most promising seems to be LiCoO 2 or LiFeO 2 and, more recently, compounds of the ternary system NiOLiCoO 2 -LiFeO 2 [3][4][5][6]. The former component presents a low resistivity (about 1 Ω.cm) and dissolves less than the NiO cathode.…”

Investigation of a Ni(Mg,Fe)O Cathode for Molten Carbonate Fuel Cell Applications

“…LiFeO 2 , on the other hand, is cheaper and has a low solubility [17], but the electrocatalytic activity for oxygen reduction [6] and the electronic conductivity are inadequate. However, binary or ternary mixtures of nickel oxide, lithium ferrite, and/or lithium cobaltite [7][8][9][10][11]15] or coatings of lithium ferrite [18] and/or lithium cobaltite (or other cobalt oxides) [19][20][21][22] on nickel oxide constitute methods for combining the useful properties of the three oxides.…”