冷却表面温差对高温质子交换膜燃料电池性能的影响OA北大核心CSTPCD

By establishing a mathematical model of high-temperature proton exchange membrane fuel cells,the heat-electricity-mass transfer characteristics in the fuel cell when there are different temperature differences on the cooling surface are simulated.The effect of temperature difference on the membrane temperature distribution,proton conductivity distribution,current density distribution,and polarization curves are analyzed.The results show that the temperature and proton conductivity in membrane decreases with the decrease of cooling surface temperature difference(temperature gradient).The local oxygen concentration in catalyst layer decreases with decreasing the temperature difference.And the current density is affected by both temperature and gas reactant concentration.A large temperature gradient results a low current density and low power density.The peak power density dropped from 0.578 W/cm2 to 0.523 W/cm2 with a decrease of 9.52%when the temperature gradient increased from 0 to 0.82 K/cm.The current density uniformity was 92.71%at the operating voltage 0.5 V and the temperature gradient 0.20 K/cm.