A membrane-less molten hydroxide direct carbon fuel cell with fuel continuously supplied at low temperatures: A modeling and experimental study

Abstract

A molten hydroxide direct carbon fuel cell (MHDCFC) is a promising electricity generation technology. Anode behavior significantly affects the cell performance. Intermittent fuel supply is a bottleneck restricting the commercialization of the cell. An MHDCFC with fuel continuously supplied is proposed in this study. Anode structural parameters are optimized through a computational fluid dynamics (CFD) model and a current model. The optimized current collector thickness, inlet number, inlet diameter are 0.2 cm, two, and 6 mm based on reactant distribution uniformity and current. Then, a membrane-less cell is built. Influence of carbon type, particle size, carbon mass fraction, and temperature on the cell performance are investigated. The cell fueled with activated carbon holding relatively large specific surface area and high conductivity achieve a higher performance. A relative small carbon mass fraction and large particle size decrease the charge transfer resistance and improve the cell performance. The cell may obtain a higher performance at 390 ℃ comparing with that under 400 ℃. The cell exhibits a power about 21 mW when activated carbon mass fraction, particle size, and temperature are respectively of 3.33%, 0.5–0.85 mm, and 390 ℃. The model and experiment demonstrate the feasibility of a continuous MHDCFC operating at a low temperature.