Anode flow field structures of micro direct methanol fuel cell

To improve the low mass transfer efficiency and poor performance of micro direct methanol fuel cells(DMFCs), a detailed study on the micro direct methanol fuel cell flow field structure is conducted in this paper. Firstly, silicon-based self-breathing DMFCs with the gird, parallel and serpentine anode flow fields were fabricated using MEMS technology. The results show that the cell performance with the single-serpentine flow field is better than those with the other structures. In addition, the single-serpentine flow field parameters were optimized, which shows that when the flow channel width: the ridge width: the flow channel length is 2:3:254, the optimum cell performance is realized. To achieve both higher mass transfer efficiency of the reactants to catalyst layer and better performance, a self-breathing DMFC with tapered serpentine anode flow fields was proposed. The results demonstrate that the maximum output power density is 15.41 mW/cm ² with the increment of 35% compared with traditional aequilatus single-serpentine flow field, which will contribute to the further development of portable micro power source systems.