Numerical study of the cathode electrode in the Microfluidic Fuel Cell using agglomerate model

• Performance of Microfluidic Fuel Cell (MFC) is predicted using agglomerate model.
• Species transport is simulated though the microchannel and catalyst layer of MFC.
• The electrochemical reaction inside the agglomerate particles is investigated.
• A set of parametric study is done in order to analyze the sensitivity of the model.

Simulation of the cathode electrode of a Microfluidic Fuel Cell (hereafter MFC) is performed with focus on the electrochemical reaction. Oxygen transport phenomena are modeled from the microchannel inlet to the reaction sites surface (on the platinum particles) in the catalyst layer. The dissolved oxygen in sulfuric acid and the formic acid are considered as the oxidant and the fuel, respectively. The cathode catalyst layer is modeled using the agglomerate model versus the homogenous model which is incapable of predicting concentration loss at high current densities. The results are validated versus the experiments of Choban et al. published in 2004. A set of parametric study is performed to investigate the influence of operating and structural parameters on the cell performance; at the end, a sensitivity analysis is implemented to rank the studied parameters with rank 1 for the most influential parameters. The results indicate that oxygen concentration at the inlet of microchannel within the range 0.1 M–0.7 M is the most influential parameter, and the cell performance can enhance by 2.615 W m−2 at the studied range. The results could be used by the microfluidic fuel cell manufacturers to overcome the current drawbacks of the MFCs.