Performance of passive DMFC with expanded metal mesh current collectors

This article assesses the feasibility of the expanded metal mesh as the current collector in the passive direct methanol fuel cell (DMFC). A single passive DMFC fixture is designed and fabricated. An acrylic supporting plate is incorporated in the cell fixture for compressing the EMCC against MEA to achieve a proper contact between the MEA and expanded metal mesh current collector (EMCC). The performance of the passive DMFC is carried out and compared with different combinations of the supporting plates and EMCCs. For this purpose, open circuit voltage, the polarization test, and electrochemical impedance spectroscopy are conducted. It is found that the configurations of the supporting plate affect the performance of the cell, and the maximum performance can be achieved by optimizing its open ratio by varying the rib configuration and rib thickness. The results reveal that the passive DMFC with EMCC gives better performance as compared to the conventional passive DMFC with circular perforated current collector and the EMCC also facilitates more fuel spreading at anode catalyst layer and increases operating temperature. Furthermore, it is seen that the mesh type and geometry of the EMCC affect the cell performance, and the passive DMFC with the coarse mesh, wider strand width and thicker EMCC produce better cell performance.