A robust protonic ceramic fuel cell with a triple conducting oxygen electrode under accelerated stress tests

Abstract

Developing protonic ceramic fuel cells is regarded as a promising approach for the electrochemical conversion of the chemical energy in hydrogen to power with high efficiency. Lowering the operating temperature can accelerate its application by integrating more reliable stack components to enable long-term durability. One critical pathway is to facilitate the oxygen reduction reaction via developing triple conducting oxygen electrodes for increasing active sites for catalysis and charge transport in bulk and interface, aiming to improve reaction kinetics. In this work, the recently developed triple conducting oxygen electrode PrNi_0.7Co_0.3O_3−δ has been examined under dynamic operating conditions to understand the degradation behaviors through an accelerated stress test. Various test protocols have been employed to measure and compare the mechanical and electrochemical performances under different dynamic parameters and thermal cycling conditions. The results strongly indicate that the as-fabricated cells exhibit a high level of endurance despite a slightly increased polarization resistance and an accelerated stress test is an effective way to examine cell reliability under more dynamic kinetics.