Two-Dimensional Numerical Simulations of Tubular Cathode in a Direct Ethanol Fuel Cell
Analytical model is a valuable tool for the design process and performance optimization of fuel cell systems. In this paper, two-dimensional mathematical models of the tubular cathode in a direct ethanol fuel cell (DEFC), which include models of catalyst layer，support body, diffusion layer and gas flow, are developed to describe not only the electrochemical kinetics on the tubular cathode, but also multi-component transfer process in the tubular cathode. The model of spherical agglomerate is used in the catalyst layer, and the effect of ethanol penetration on oxygen reaction of the tubular cathode is also considered. Based on the model, Comsol Miphysics is used to simulate the concentration distribution of components and the current density distribution. Additional, the influence of diffusion layer and catalyst layer in the tubular cathode and the cell operating conditions on the performance of DEFC are analyzed. The results show that the mass transfer resistance exists in the diffusion layer, and the gas concentration decreases inside the battery. It is further showed that electrochemical reactions mainly happen in the catalyst layer, and oxygen concentration decrease rapidly at this time, while the water concentration can be increased.
D. Tang et al., "Two-Dimensional Numerical Simulations of Tubular Cathode in a Direct Ethanol Fuel Cell", Advanced Materials Research, Vols. 311-313, pp. 2362-2366, 2011