Abstract
The purpose of this paper is to investigate the performance characteristics of direct dimethyl ether fuel cell (DDMEFC) at various operating conditions. The experiment was performed under various operating conditions such as the operating temperature, cathode flow rate, anode backpressure, and cathode backpressure. In this experiment, the test fuel cell was a single fuel cell and catalysts were loaded with Pt-Ru(4mg/cm2) and Pt-black(4mg/cm2) at the anode and cathode, respectively. Both anode and cathode flow patterns were machined with serpentine flow type in graphite plates. And, the dimethyl ether (DME) aqueous solution and humidified air were supplied for hydration of the membrane. The polarization curve of DDMEFC was obtained by measuring of voltage-current density via a potentiostatic method. In addition, the DME crossover current was measured to determine crossover loss from anode to cathode in DDMEFC. It was found from the result that the DDMEFC performance was significantly enhanced with the increase of operating temperature and anode backpressure due to the high ion conductivity and active electrochemical reaction. Also, the performance was increased by increasing of anode backpressure because the oxidation reaction was activated with catalyst. And, the crossover current was also increased due to the diffusion of DME solution and high electro-osmotic drag.
Keywords: Fuel cell, Dimethyl ether (DME), Operating condition, Performance, Crossover current