Effect of anode gas mixture humidification on the electrochemical performance of the BaCeO3-based protonic ceramic fuel cell

Abstract

In this work a tape-calendering method has been adopted to fabricate an anode-supported proton ceramic fuel cell (PCFC) with a 50 μm BaCe0.89Gd0.1Cu0.01O3–δ proton-conducting electrolyte. In order to evaluate the feasibility of the method the PCFC's characteristics such as open-circuit voltage, power density, ohmic and polarization losses were investigated with special attention being given to the effects of water vapor partial pressure in an anode gas mixture on the PCFC's performance and the transport properties of the electrolyte. It was found that the proton transport number of the electrolyte increases significantly with increased water content which ensures greater efficiency of the PCFC due to more complete fuel utilization. The electrodes contribute 50% of the total voltage drop of the developed PCFC element at 600 °C and 25% at 750 °C. This is principally due to the tangible contact resistance between the cathode and the electrolyte as well as the low electrocatalytic activity of the Pt cathode. The anode atmosphere humidification can be considered as a perspective strategy for further enhancement of PCFC's performance.