A More Flooding-Tolerant Oxygen Electrode in Alkaline Electrolyte

Owing to the inherent performance and cost advantages alkaline fuel cells (AFCs) have been being a highlight in fuel cells research. However the degradation of the performance coming from the cathode due to the oxygen diffusion limit leaded by the flooding is a critical issue to overcome. The objective of this study is thus devoted to mitigate the water flooding happening in the pores of a porous oxygen electrode by using a more flooding-tolerant electrode (FTE) which contains water-proof oil, dimethyl-silicon-oil (DMS). The FTE performance was checked in two cases, the whole FTE completely immersed in 1 mol L-1 KOH, and its catalyst layer side exposed to 1 mol L-1 KOH but its back side to gas chamber, in order to simulate the situation of electrode flooded and electrode at normal operation condition, respectively. The results indicate that the FTE displays outstanding flooding-tolerant capability, especially in the case of a large current density, in which mass transport of gas reactant is in a dominant position.