Performance evaluation and mechanism study of a dual-electrolyte self-pumping microfluidic fuel cell

Abstract

The two-dimensional model of a dual-electrolyte self-pumping microfluidic fuel cell with Pd-coated carbon cloth electrodes is created based on multidisciplinary theory in this study. Multiple physical fields are coupled to investigate the internal operating mechanism of the fuel cell. In addition, the accuracy of the numerical model is verified by comparing the simulation results with experimental data when the fuel concentration is 1 M and 2 M, respectively. The data shows that when the concentration of fuel (sodium formate solution) is 2 M, the simulation results match up with the experiment. To sum up, this model can obtain the best performance only if the polyacrylamide gel of the fuel cell happens to be in contact with the electrodes (the gel position: x = 2 cm and the gel width: y = 2 mm), and the aspect ratio of the electrode and current collector is 1:1 (both 1 cm). Observed from the polarization plots and power density curves, the cell can generate a maximum current density of 29.61 mA/cm2 and a maximum power density of 8.87 mW/cm2, which is superior to most cells powered by capillary force. Fuel utilization is also used to evaluate the cell performance with a value of 5.75 %.