摘要
燃料饥饿的发生,将加速质子交换膜燃料电池(PEMFC)的衰减,降低电池的寿命。在燃料饥饿条件下,采用分式结构电池,对其电压、电极电势、电流分布及局部界面电势随时间的响应情况进行了在线测量。实验结果表明在燃料饥饿条件下,电池阳极侧出现"真空效应",公用管路内燃料气被倒吸进电池阳极,延缓了电池的死亡。公用管路内气体氢浓度越低,电池衰减越快。在此过程中,电池阳极中间区域局部界面电势首先上升,相应的阳极电势也逐渐升高;同时,电池中间区域电流下降,电流分布差异增大,阴极极化增大,电势相应下降。这表明电池运行过程中,气体中所含杂质在电池阳极的积累,使得电池阳极腔内氢气浓度逐渐下降并最终引起电池死亡。
The occurrence of fuel starvation would cause accelerated degradation of proton exchange membrane fuel cell（PEMFC） and decrease its lifetime.In this paper,the changes of cell voltage,anode and cathode potentials,current distribution and local interfacial potentials with time were detected in situ using a segmented cell under fuel starvation conditions.The experimental results show that under fuel starvation conditions,＂vacuum effect＂ happens in the anode,and fuel in the manifold is drawn to the cell,which delays the death of the cell.The lower the hydrogen concentration of fuel in the manifold,the sooner the cell dies.In this period,the local interfacial potential of the anode middle region increases firstly,and the anode potential increases gradually.While the cathode potential decreases gradually,because larger cathode polarization is caused by the more uneven current distribution due to the decrease of the currents in the middle segments.The experimental results indicate that the accumulation of impurity in the anode would results in the gradually decreasing of hydrogen concentration in the anode and finally the cell death.
出处
《电源技术》
CAS
CSCD
北大核心
2010年第8期767-770,共4页
Chinese Journal of Power Sources
基金
国家"863"计划(2007AA05Z127)
国家自然科学基金项目(20876155)资助
关键词
质子交换膜燃料电池
燃料饥饿
电流分布
局部界面电势
proton exchange membrane fuel cell（PEMFC）
fuel starvation
current distribution
local interfacial potentials
