Development of semi-empirical cell voltage model for direct methanol fuel cell

Abstract

A new semi-empirical model is established to describe the cell voltage of a direct methanol fuel cell (DMFC) as a function of current density. The proposed model focuses on very unfavorable conditions for the cell operation, i.e. low methanol solution concentrations and relatively low cell temperatures.. The model equation is validated experimental data over a wide range of a methanol concentration and temperatures. A number of existing models are semi-empirical. They, however, have a serious mathematical defect. In their models, when the current density,;', becomes zero, the cell voltage goes to the infinity. A newly developed semi-empirical equation corrects this mathematical defect and includes the methanol crossover effect that plays a major role in determining the cell voltage of DMFC. The model equation is validated experimental data over a wide range of a methanol concentration and temperature.