热处理不锈钢用作质子交换膜燃料电池双极板

Application of heat treatment of 304 stainless steel as bipolar plates of PEMFC

双极板是质子交换膜燃料电池的关键部件之一,其性能的好坏不但影响电池的性能,而且影响电池的成本,成为燃料电池产业化的瓶颈。通过高温热处理不锈钢板,使不锈钢中碳与其中的铬等金属反应,在不锈钢的表面生成导电的金属碳化物晶粒,减小不锈钢与电极的接触电阻。实验结果表明,304不锈钢经过空气气氛下,820℃处理1h后,与柔性石墨的接触电阻降低了4～5倍,200h腐蚀实验后,测定的接触电阻没有明显增加,表明通过热处理技术可以在不降低耐腐蚀性能的前提下,减小不锈钢与石墨的接触电阻,使其可以用做质子交换膜燃料电池双极板。

Bipolar plate for proton exchange membrane fuel cell is one of the critical components which influence not only the performance but also the cost of the stack. It has been the chokepoint for the industrialization of PEMFC. Through high heat-treatment for the stainless steel, the carbon reacted to the Cr and other metals. The electric carbides on the surface were made. Therefore contact resistance between the stainless steel and the electrode was reduced. Results of the experiment indicate that the stainless steel which are heat-treated at definite conditions can depress the contact resistance than original stainless steel for 4-5 times. After 200 h corrosion experiment, the contact resistance doesn＇t increase obviously. It makes clear that the stainless steel which was trained by heat-treatment can depress the contact resistance between the stainless steel and graphite in condition of having no affect on the resist-corruption performance. Hence it can be used to make the bipolar plates of PEMFC.