酸性环境对PEM燃料电池垫片材料机械性能影响

Effects of acidic environments on mechanical properties of gasket material in PEM fuel cells

垫片材料的稳定性对质子交换膜(PEM)燃料电池的密封和电化学性能至关重要。采用实验方法研究了一种潜在的P EM燃料电池垫片用材料——甲基乙烯基硅橡胶材料在酸性环境下的老化损伤情况。采用机械性能实验分别对未老化的试样和在酸性环境下老化试样进行机械性能测试,研究酸性环境对PEM燃料电池垫片材料机械性能的影响。实验结果表明,酸性环境对PEM燃料电池垫片材料的机械性能有重要影响。在相同老化时间下,随酸性程度的增加,试样抗拉强度和断裂伸长率随之降低;压缩永久变形实验和压缩应力松弛实验结果表明,试样压缩永久变形随酸性程度的增加而增大,而试样压缩应力松弛模量随酸性程度的增加而降低。

The stability of gasket material is critical to sealing and electrochemical performance of proton exchange membrane(PEM)fuel cells.The degradation of the methyl vinyl silicone rubber material,namely one of potential gasket materials for PEM fuel cells,was investigated experimentally in acidic environments.The mechanical property tests were conducted for the samples before and after exposure to the acidic environments.And then,the effects of the acidic environments on the mechanical properties of the gasket material used for the PEM fuel cells were studied.The test results show that the acidic environments have an important effect on the mechanical properties of the gasket material in PEM fuel cells.The tensile strength and elongation at break decreased with the increase of the acidic concentration at the identical aging time.The test results of compression set and compression stress relaxation for the samples indicate that the value of the compression set increases with the increase of the acidic concentration,and the compression stress relaxation modulus decreases with the increase of the acidic concentration.