直接甲醇燃料电池膜电极性能衰退原因的分析  

Investigation of performance degradation of electrodes in direct methanol fuel cell

作　　者：赵新生[1] 樊小颖[1] 汪国雄[1] 王素力[1] 孙海[1] 衣宝廉[1] 辛勤[1] 孙公权[1] 

机构地区：[1]中国科学院大连化学物理研究所,辽宁大连116023

出　　处：《电源技术》2005年第4期227-230,265,共5页Chinese Journal of Power Sources

基　　金：国家高技术发展计划项目(2003 A A 517040);国家自然科学基金资助项目(20173060);中国科学院知识创新工程重要方向和领域前沿项目(K G CX 2-SW -310;K 2003 D 2)

摘　　要：分析了直接甲醇燃料电池在长时间运行过程中膜电极(Membraneelectrodeassembly,MEA)性能衰退的原因。电池经过86h的恒电流放电后,比功率由130mW·cm-2降为100mW·cm-2,现场(In-Situ)交流阻抗技术对电池放电全程监测的结果显示了电池的欧姆电阻、电荷转移电阻和传质阻力随放电时间的延长逐渐增大;循环伏安测试的结果表明,放电后电极的有效电化学反应表面积有所减小;通过扫描电子显微镜(SEM)观察了放电后MEA断面形貌,发现催化层与Nafion膜间存在明显剥离,增大了质子传导阻力。上述因素的综合作用导致了膜电极的衰退。A direct methanol fuel cell showed a rapid decay in performance after continuous operation of 86 h.Various analysis tools including electrochemical impedance spectroscopy (EIS), cyclic voltammogram (CV), scanning electronic microscopy (SEM) were used to investigate the causes of performance degradation of the single cell during its long-term operation. The EIS results showed that ohm resistance, charge transfer resistance and mass transport resistance increased with discharging time. The active surface area of electrodes was reduced after life test. Compared to the cross-section image of that before test, the delamination in MEA was found after 86 h operation.

关 键 词：直接甲醇燃料电池 膜电极 性能衰退 交流阻抗谱 

分 类 号：TM911.4[电气工程—电力电子与电力传动]