Experimental Investigation of the Porous Nickel Anode in the Molten Carbonate Fuel Cell

Abstract

The electrochemical performance of the porous nickel anode in a molten carbonate fuel cell was experimentally investigated in this study. The electrode structure was studied by scanning electron microscope and Hg porosimetry. The effect of electrolyte filling, on overpotential at a constant current density, was also examined. Kinetics for the hydrogen reaction was studied by obtaining stationary polarization curves, for porous nickel anodes at varying temperatures and anode gas compositions. The slopes of these polarization curves were analyzed at low overpotentials, with the assumption that the porous anode was under kinetic control, and the corresponding exchange current densities were determined using a simplified porous electrode model. The obtained partial pressure dependencies of the exchange current density were high, and therefore, difficult to explain by the generally assumed mechanisms. © 2001 The Electrochemical Society. All rights reserved.