Electrical Characterization of a Glucose-Fueled Alkaline Fuel Cell

This paper is part of an effort to establish design parameters for glucose-fueled room temperature membraneless alkaline fuel cells as possible electricity suppliers for portable devices. We report experimental results for three characteristics of glucose-fueled room temperature membraneless alkaline fuel cells: 1) polarization curve, 2) power density as a function of current density, and 3) internal resistance. The internal resistance of the cell was measured by two independent experimental methods: “Voltage Divider” and “Current Interrupt”. The three characteristics were measured as a function of glucose concentration while maintaining the electrolyte, KOH, constant at 0.35 M. The results were compared with those reported for other room temperature Alkaline Fuel Cells fuelled with glucose and methanol. We found that the maximum power density has a value of 0.36 mW/cm2 at a current density of 1.44 mA/cm2 when glucose concentration is 0.22M. The “Voltage Divider” and “Current Interrupt” methods for measuring the internal resistance produced practically the same results. The resistivity of the electrolyte/fuel solution was estimated from internal resistance measurements. Resistivity was found to be linearly dependent upon glucose concentration; at a constant KOH electrolyte concentration of 0.35 M, the specific resistivity of 1 M glucose is 2.56 Ω·m. The power density obtained with Alkaline Fuel Cells fuelled with glucose is an order of magnitude smaller than that obtained for cells fuelled with methanol. More efforts should be invested in order to develop a practical glucose-fuelled fuel cell.