Effect of LiNiO2-coated cathode on cell performance in molten carbonate fuel cells

Abstract A double-layered electrode by coating a layer of nano-sized LiNiO 2 particles on a conventional electrode was fabricated to improve the performance of the cathode of the molten carbonate fuel cell. The layer consisting of nano-sized LiNiO 2 particles has a larger surface area than that of the conventional electrode, which is a lithiated NiO cathode. Therefore, it can provide numerous reaction sites and has higher electrical conductivity than the lithiated NiO electrode. Consequently, the cell performance can be improved at lower operating temperatures (600 °C or below). The performance of the nano LiNiO 2 -coated cathode was examined in various ways such as by single-cell operation and electrochemical impedance spectroscopy (EIS). The improvement in performance was demonstrated by high cell voltage of over 0.87 V at 600 °C and current density of 150 mA cm −2 . This result was better than 0.81 V generated by the uncoated cathode cell. In the EIS analysis, the nano LiNiO 2 layer coating tended to significantly decrease the charge transfer resistance and increase the mass transfer resistance but caused an overall decrease in the cathode polarization. Thus, high performance was observed at low temperatures.