Study on PCFC Total Voltage Loss Analysis by Current Interruption Technique to Separate IR Drop and Overvoltage

Abstract

The voltage loss factors in Protonic Ceramic Fuel Cell (PCFC) are caused by anode polarization, cathode polarization and voltage drop by internal resistance. In this paper, an analytical method which divides the total voltage loss into the ohmic loss, anode overvoltage, and other overvoltage by current interruption technique has been reported. Firstly, applying the develop method to analysis of voltage loss factors, the number of RC parallel elements can be determined as seven from the voltage relaxation waveform without assuming the number of elements in advance. Secondly, it was revealed that the overvoltage η1 which is the smallest time constant in seven elements is caused by the hydrogen concentration in the fuel and steam concentration in the Air electrode. Moreover, it was revealed that and the overvoltage η3 and η4 are caused by the oxygen concentration and steam concentration in the air electrode. Especially, η5 is caused by oxygen in air electrode. On the other hands, it could not clearly separate the overvoltage η2 which might be caused by the hydrogen, oxygen, and steam concentration in the fuel electrode but also η6 to η7 in this study.