基于微观格点模型模拟PEMFC定向结构催化层

用微观格点模型对质子交换膜燃料电池(PEMFC)定向结构阴极性能进行了模拟,并与随机结构电极进行了对比,研究了催化剂利用率及电池性能的变化.计算了催化层内的传递和电化学反应,研究了质子、氧气及电化学反应速率在电极厚度方向上的分布,并且通过对比氧气浓度、离子电势和电化学反应速率的分布,证明了Pt/C颗粒在电极厚度方向上定向排布有利于提高电池性能.另外,研究了电极厚度对定向结构电极性能的影响,发现与随机结构电极不同,定向结构电极厚度越小,高电流密度下电极性能越好.

Simulation of Orientated Catalyst Layer in PEMFC Using a Microstructure Lattice Model

The orientated cathode in a proton exchange membrane fuel cell was simulated and compared with a random cathode using a microstructure lattice model. The differences between catalyst utilization and electrode performance were studied. Transport and electrochemical reactions in the model catalyst layer were calculated. The orientated cathode performed better than the traditional random cathode and was explained by variations of the oxygen levels, the over potential and the reaction rate across the catalyst layer with cell current density. Additionally, we examined the electrode performance at different thicknesses. Unlike the traditional random cathode, a thinner orientated cathode performed better.