质子交换膜燃料电池电压损耗  

Polarization of the membrane electrode assembly in a proton exchange membrane fuel cell

作　　者：赵阳[1] 王树博[1] 李微微[1] 谢晓峰[1] ZHAO Yang;WANG Shubo;LI Weiwei;XIE Xiaofeng(Institute of Nuclear and New Energy Technology,Tsinghua University,Beijing 100084,China)

机构地区：[1]清华大学核能与新能源技术研究院,北京100084

出　　处：《清华大学学报（自然科学版）》2020年第3期254-262,共9页Journal of Tsinghua University(Science and Technology)

基　　金：国家重点研发计划项目(2017YFB0103003,2017YFB0103003).

摘　　要：质子交换膜燃料电池电压损耗的定量分析,对于寻求膜电极性能的提升空间具有重要的参考意义。该文以实验室自制的膜电极为研究对象,对其内部损耗、ohm极化、活化极化以及浓差极化依次进行了实验分析。结果表明:在阴极铂载量为0.2 mg/cm^2的膜电极中,活化极化在整体电压损耗中所占比例最高,这一现象在低温下愈发明显;ohm极化的占比最小,电流密度为1550 mA/cm^2时,其最大值约为0.09 V;浓差极化在低电流密度区域的影响较小,在大电流密度区域以指数形式增长。经过对浓差极化的分析发现,40%~44%的氧气扩散阻力主要来源于气体扩散层内的分子扩散阻力,43%~50%的氧气扩散阻力主要来源于氧气穿过离聚物层到达铂表面的阻力。The performance of a proton exchange membrane fuel cell depends on the membrane electrode assembly(MEA)polarization.The characteristics of a home-made MEA with various polarizations were measured to calculate the internal losses,activation polarization,ohmic polarization,and mass transfer polarization.The results show that the activation polarization has a large effect,especially at low temperatures,while the ohmic polarization has little effect with a maximum difference of about 0.09 V for a current density of 1550 mA/cm^2.The mass transfer polarization effect increases rapidly as the current density increases.Moreover,40%—44%of the oxygen transport resistance comes from the molecular diffusion resistance in the gas diffusion layer with 43%—50%of the resistance originating from the oxygen dissolution and diffusion through the ionomer layer.

关 键 词：质子交换膜燃料电池 电压损耗 活化极化 ohm极化 浓差极化 

分 类 号：TM911.4[电气工程—电力电子与电力传动]