Performance of a hybrid direct ethylene glycol fuel cell

Abstract

In this work, a hybrid fuel cell is developed and tested, which is composed of an alkaline anode, an acid cathode, and a cation exchange membrane. In this fuel cell, ethylene glycol and hydrogen peroxide serve as fuel and oxidant, respectively. Theoretically, this fuel cell exhibits a theoretical voltage reaching 2.47 V, whereas it is experimentally demonstrated that the hybrid fuel cell delivers an open-circuit voltage of 1.41 V at 60°C. More impressively, this fuel cell yields a peak power density of 80.9 mW cm−2 (115.3 mW cm−2 at 80°C). Comparing to an open-circuit voltage of 0.86 V and a peak power density of 67 mW cm−2 previously achieved by a direct ethylene glycol fuel cell operating with oxygen, this hybrid direct ethylene glycol fuel cell boosts the open-circuit voltage by 62.1% and the peak power density by 20.8%. This significant improvement is mainly attributed not only to the high-voltage output of this hybrid system design but also to the faster kinetics rendered by the reduction reaction of hydrogen peroxide.