Transmission characteristics of cathode water in direct methanol fuel cell

The characteristic of cathode water transport in direct methanol fuel cell was investigated using COMSOL Multiphysics, including the effect of the distribution of pressure, velocity, water, oxygen and liquid saturation, as well as diffusion layer under different physical parameters, such as thickness, porosity, size and hydrophobicity. A further mathematical model of diffusion layer with gradient porosity distribution was established to study the effect of porosity gradient and support layer parameters on cell performance and mass transfer. The results show that the diffusion layer with high porosity and thin layer is beneficial to oxygen transfer. The gradient porosity distribution of diffusion layer can reduce oxygen transport resistance, and thus improving the cell performance.