PEMFC新型压差流道传质与电化学性能研究

双极板是质子交换膜燃料电池（PEMFC）核心组件，极板的流道形状和尺寸直接影响反应气体的利用率以及电池的排水、散热性能。基于极板工作原理提出一种新型PEMFC压差流道构型，研究流道内阴极氧气浓度、水浓度分布、进出口压降、流速的变化，分析电流密度和极化曲线对燃料电池电化学性能的影响；50%开孔率时，对比8组低压直流道和高压直流道宽度同时增大的仿真结果发现，低压直流道和高压直流道宽度均由2.25mm减小到0.5mm时，功率密度峰值提高了31.9%。进一步探究压差流道中增大或保持一种流道宽度不变去改变另一种流道宽度对燃料电池电化学性能影响，结果表明低压直流道和高压直流道宽度均为1mm时，功率密度峰值最高可达0.39W/cm2。

Study on Mass Transfer and Electrochemical Performance of PEMFC with Novel Differential Pressure Flow Channel

Bipolar plate is the core component of proton exchange membrane fuel cell (PEMFC). The shape and size of flow channel on the plate directly affect the utilization rate of reaction gas and the drainage and heat dissipation performance of the battery. Based on the working principle of plate, a new configuration of differential pressure channel for PEMFC was proposed.The changes of cathode oxygen concentration,water concentration distribution, inlet and outlet pressure diffierences and flow rate were studied.The effects of current density and polarization curve on the electrochemical performance of fuel cells were analyzed; Compare the 8 groups with 50% opening rate of low pressure and high pressuree straight channel width increasing at the same time,the simulation results show that the peak power density increases by 31.9% when the width of low pressure straight channel and high- pressure straight channel decreas from 2.25mm to 0.5mm. The influence of increasing or maintaining the width of one channel while changing the other channel width on the electrochemical performance of the fuel cell is further explored. The results show that when the width of both low- pressure straight channel and high- pressure straight channel are 1mm, the peak power density can reach up to 0.39W/cm2.