冷却表面温差对高温质子交换膜燃料电池性能的影响  

Influence of cooling surface temperature difference on the high temperature proton-exchange membrane fuel cell performance

作　　者：王金山 王世学[1,2] 朱禹 WANG Jinshan;WANG Shixue;ZHU Yu(School of Mechanical Engineering,Tianjin University,Tianjin 300350,China;National Industry-Education Platform of Energy Storage(Tianjin University),Tianjin 300350,China)

机构地区：[1]天津大学机械工程学院,天津300350 [2]天津大学国家储能技术产教融合创新平台,天津300350

出　　处：《化工学报》2024年第5期2026-2035,共10页CIESC Journal

基　　金：国家重点研发计划项目(2021YFB3800400)。

摘　　要：通过建立高温质子交换膜燃料电池数学模型,模拟了冷却表面存在不同温差时燃料电池内热-电-质的传输特性,分析了温差对电池内温度分布、氧浓度分布、极化曲线、膜质子电导率和电流密度的影响。结果表明:膜内温度和质子电导率随着冷却表面温度的降低而降低;催化层内的局部氧浓度随着冷却表面温差(即温度梯度)的增大而增大,但电流密度受温度及反应物浓度双重因素影响,电流密度及功率密度随着温度梯度的增大而下降。当冷却表面温度梯度从0增加至0.82 K/cm时,峰值功率密度从0.578 W/cm2下降到0.523 W/cm2,下降了9.52%。控制工作电压大于0.5 V、温度梯度小于0.20 K/cm时可获得较好的电流密度均匀性。当工作电压为0.5 V,冷却表面温度梯度为0.20 K/cm时,电流密度均匀性为92.71%。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.

关 键 词：燃料电池 传热 传质 数值模拟 电流密度均匀性 

分 类 号：TK91[动力工程及工程热物理]