Dynamic modeling of transient response of direct methanol fuel cell

Transient response is an important characteristic of a fuel cell system, which allows understanding of system ability to respond to a sudden change in the load. This paper introduces an electrochemical simulation model for direct methanol fuel cell (DMFC) to study the transient response and the load-following capability of the fuel cell. The model also accounts for undesired methanol crossover and overpotentials. Unlike proton exchange membrane fuel cell (PEMFC), DMFC uses methanol as fuel hence overcoming the need of reformer. The model developed is initially tested with linearly increasing load to verify the steady state characteristic of the fuel cell. To study the transient response and the load-following capability of the fuel cell a step change and rapidly changing residential loads are used. The simulation results show smooth transient response and fast load-following capability of DMFC with rapidly varying load. All simulations are performed using MATLAB^® and Simulink^®.