PEMFC双极板复合镀层的耐腐蚀和导电性能

Corrosion resistance and electrical conductivity of composite coatings on bipolar plates for PEMFC

采用真空电弧离子镀的方法在质子交换膜燃料电池(PEMFC)不锈钢双极板表面制备复合镀层,通过界面接触电阻研究镀层的导电性能。模拟燃料电池环境,研究镀层对双极板耐腐蚀性能的影响。316L不锈钢、Au/TiN和C/TiN镀层在1.5 MPa的压力下的界面接触电阻分别为30.33 mΩ·cm^(2)、3.46 mΩ·cm_(2)和4.54 mΩ·cm^(2);在模拟阴极环境下的腐蚀电流密度分别为5.12×10^(-7 )A/cm^(2)、1.24×10^(-8) A/cm^(2)和1.36×10^(-8) A/cm^(2);在模拟阳极环境下的腐蚀电流密度分别为2.30×10^(-6) A/cm^(2)、1.14×10^(-7) A/cm^(2)和7.89×10^(-8) A/cm^(2)。相较于不锈钢基材,Au/TiN和C/TiN镀层可提高双极板的导电性能和耐腐蚀能力。

Composite coatings were prepared on stainless steel bipolar plates for proton exchange membrane fuel cell(PEMFC)substrate by vacuum arc ion plating method.Electrical conductivity of coatings was investigated by interfacial contact resistance.The influence of coatings on corrosion resistance of bipolar plate was studied by simulating the operating environments of fuel cell.The interfacial contact resistances of 316L stainless steel,Au/TiN coating and C/TiN coatings under 1.5 MPa compaction forces were 30.33 mΩ·cm^(2),3.46 mΩ·cm^(2) and 4.54 mΩ·cm^(2),respectively.The corrosion current densities in simulated cathode environment were 5.12×10^(-7) A/cm^(2),1.24×10^(-8) A/cm^(2) and 1.36×10^(-8) A/cm^(2),the corrosion current densities in simulated anode environment were 2.30×10^(-6) A/cm^(2),1.14×10^(-7) A/cm^(2) and 7.89×10^(-8) A/cm^(2),respectively.Compared with stainless steel,Au/TiN and C/TiN coated stainless steel could improve electrical conductivity and corrosion resistance for bipolar plates.