304不锈钢双极板在模拟PEMFC环境中的性能

Performance of 304 stainless steel bipolar plate in simulated PEMFC environments

为降低质子交换膜燃料电池(PEMFC)的生产成本,选择成本低廉、强度高、化学稳定性好的不锈钢材料替代传统的石墨双极板.以304不锈钢为研究对象,采用电化学方法测定其在模拟PEMFC环境下的极化曲线和对应于PEMFC工作电位下的恒电流极化曲线,用伏安法测量304不锈钢表面氧化膜/钝化膜与碳纸之间的接触电阻.结果表明,在模拟PEMFC环境中,304不锈钢钝化电流密度低于16μA/cm2,电流没有出现明显的波动;304不锈钢在模拟PEMFC环境中表面生成的钝化膜的接触电阻大于空气中形成的氧化膜的接触电阻.

Stainless steel 304 was selected as bipolar plate to substitute for graphite plate to reduce the production cost of proton exchange membrane fuel cell （PEMFC）. The electrochemical methods were investigated in a simulated PEMFC environment and the volt-ampere technique was applied to measure interracial contact resistance between the sample and carbon paper. The results show that stainless steel 304 has low passivation current density and it is smaller than 16 μA/cm^2 in the simulated PEMFC environment and it is not obviously fluctuant. The interracial contact resistance between the passive film and carbon paper is higher than that between the oxide film and carbon paper.