反应气相对湿度影响电池内部水的输运和质子膜的质子传导率,合适的反应气湿度可改善电池性能。利用三维数值模型分析反应气相对湿度对直通流道和交叉流道质子交换膜燃料电池性能的影响。模拟结果表明,当阳极反应气相对湿度为100%时,低操作电压条件下,降低阴极反应气相对湿度有利于电池性能提高,然而在高操作电压条件下,电池性能随阴极相对湿度的增加而提高;当阴极反应气相对湿度为100%时,低操作电压条件下,降低阳极反应气相对湿度,电池性能提升,高操作电压条件下,电池性能不依赖于阳极反应气相对湿度。通过对电池内部局部传递特性的分析,从质子交换膜湿润性及阴极传质限制两方面分析探讨了反应气相对湿度对电池性能影响的原因。
Relative humidity (RH) of reactant affects the local water transport and membrane conductivity, and an appropriate RH of reactant can improve cell performance of the PEMFC. A three-dimensional numerical model was used to examine the effect of RH of reactants on the performance of the PEMFCs with parallel and interdigitated flow channels. The results show that, with the anode RH of 100%, at low operating voltages, the cell performance decreases as cathode RH increases, while at high operating voltages it is just the opposite. With the cathode RH of 100%, at high operating voltage, the cell performance is not depending on the anode RH, while at low operating voltage, the cell performance is improved as the anode RH reduced. The effect of reactant RH on the cell performance was discussed based on analyzirlg the local transport phenomena in the cell.