Determination of component drags coefficients in direct methanol fuel cell

Abstract

Direct Methanol Fuel Cell (DMFC) system is considered as one of the most important clean and sustainable energy generation system. This system generates energy by electro oxidization of methanol however, this reaction is not fully completed. Consequently, the efficiency of the system is lower than expected. Studies in literature generally assume a fully completed methanol electrooxidation reaction (MOR) however, since MOR is not fully completed in this system. Thus, it is significant to consider the reaction intermediates. Therefore, this study focused on evaluating some critical parameters such as diffusion coefficients, component drag coefficients, and activation energies by considering reaction intermediates forms from MOR at the operating conditions. According to the experimental data, the properties of electroosmotically dragged substances in an operating DMFC system were investigated. First, the polarization curve was obtained, and then the system was run at constant current density for mid-term experiments. Next, the effect of the changes in DMFC operating conditions on performance was examined. Accordingly, component drag coefficients at 55 °C for methanol and water were obtained as 0.000246 and 3.1, respectively.