具有梯度结构扩散层的质子交换膜燃料电池性能研究

Research on Proton Exchange Membrane Fuel Cell with Gradient Gas Diffusion Layer

为了考察质子交换膜燃料电池气体扩散层孔隙率的梯度变化对扩散层排水、导电、导气以及电池整体性能的影响,在综合考虑电化学反应、水的生成、相变及传输、氧气传输、膜中水传输等因素的基础上,研究了扩散层孔隙率沿厚度方向梯度变化时燃料电池内部的传输现象和电池性能.结果表明,梯度扩散层能够提高液态水和气体的通过能力,从而提高电池的性能,且孔隙率梯度越大排水性能越好.

In order to investigate the influence of gradient gas diffusion layer （GDI.） in proton exchange membrane fuel cell （PEMFC） on discharging water, conducting electricity and diffusing gas in GDL and the total performance of the cell, the transport phenomena in the fuel cell and its performance that has GDLs with gradient porosity along the thickness are numerically investigated. The results show that the gradient GDL has larger water flux and better gas diffusion effects than the uniform GDL has, thus improves the performance of the cell. Moreover, bigger the porosity gradient is, more powerful the discharging ability of GDL is.