工作电压对PEMFC膜电极衰退影响模拟研究  

Numerical study of the effects of operating voltage on the degradation of membrane electrodes of PEMFC

作　　者：谭耀文 姜攀星 杜青 余婉秋 温小飞 詹志刚[1,2] TAN Yaowen;JIANG Panxing;DU Qing;YU Wanqiu;WEN Xiaofei;ZHAN Zhigang(State Key Laboratory of Advanced Technology for Materials Synthesis and Processing,Wuhan University of Technology,Wuhan 430070,Hubei,China;Hubei Key Laboratory of Fuel Cells,Wuhan 430070,Hubei,China;Donghai Laboratory,Zhoushan 316022,Zhejiang,China)

机构地区：[1]武汉理工大学材料复合新技术国家重点实验室,湖北武汉430070 [2]燃料电池湖北省重点实验室,湖北武汉430070 [3]东海实验室,浙江舟山316022

出　　处：《化工学报》2024年第3期974-986,共13页CIESC Journal

基　　金：国家自然科学基金项目(22179103,21676207);东海实验室开放基金项目(DH-2022KF0305)。

摘　　要：为研究长期稳定运行条件下,工作电压对质子交换膜燃料电池膜电极衰退状况的影响,建立了包含碳腐蚀、Pt氧化与溶解以及离聚物降解的PEMFC多物理场耦合模型进行数值模拟。研究结果表明:随着工作电压增加,阴极催化层中Pt溶解与碳腐蚀速率加快,500 h后Pt表面氧化的区域大幅增加,阴极催化层中团聚体半径与质子交换膜中磺酸基团浓度剧烈减小,衰退区域主要集中在阴极入口处且高电压下衰退程度急剧增加。电池在0.8 V下运行500 h后,阴极入口处阴极催化层与膜厚度显著减小,分别降低13.62%与35.30%;阴极催化层电化学活性面积和膜的离子电导率分别减小59.9%与6.9%,膜的当量质量增加7.4%,且上述指标前100 h内衰退剧烈,随后逐渐趋于平缓。可为膜电极材料设计与控制策略的优化提供参考。To study the effect of operating voltage on the degradation of membrane electrodes of proton exchange membrane fuel cell(PEMFC)under long-term stable operation conditions,a coupled multi-physics field PEMFC model including carbon corrosion,Pt oxidation,dissolution and ionomer degradation is established for numerical simulation.The results show that as the operating voltage increases,the Pt dissolution and carbon corrosion rates in the cathode catalytic layer accelerate.After 500 h,the oxidized area of the Pt surface increases significantly.The radius of the agglomerates in CCL and the concentration of sulfonic acid groups in the proton exchange membrane decrease drastically,and the recession area is mainly concentrated in the cathode inlet and the degree of the recession is increased drastically at a high voltage.When the cell is operated at 0.8 V for 500 h,the thickness of CCL and membrane at the cathode inlet decreased significantly by 13.62%and 35.30%,respectively.The electrochemcial active surface area of CCL and the ionic conductivity of the membrane decreased by 59.9%and 6.9%,respectively,and the equivalent weight of the membrane increased by 7.4%,and the above indexes declined drastically in the first 100 h,and then gradually stabilized.The conclusion can provide a guideline for the optimization of membrane electrode material design and control strategy.

关 键 词：质子交换膜燃料电池 膜电极 工作电压 计算流体力学 衰退 模拟 

分 类 号：TM911.4[电气工程—电力电子与电力传动]