Cathode materials (NiO–LiFeO2–LiCoO2) for molten carbonate fuel cell: A diffraction, NMR and conductivity study

The search for a NiO-based cathode for molten carbonate fuel cell has been directed towards solid solutions containing LiFeO2 and LiCoO2 in addition to nickel oxide [A. Wijayasinghe, B. Bergman, C. Lagergren, Electrochim. Acta 49 (2004) 4709.]. NiO and LiFeO2 are fully soluble in one another, while ternary solid solutions have been previously obtained only for small (< 18%) and high (> 90%) LiCoO2 molar contents. The goal of this work is to identify and characterize the compositions with the most promising electrical conductivity, which may be used as cathode materials. We present data relative to compositions having a constant NiO/LiFeO2 molar ratio of 3:1 and a LiCoO2 content from 5 to 30 mol%.