• Title/Summary/Keyword: Surface Passivation

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Performance assessment of Magnesium Bipolar Plates for Light Weight PEM Fuel Cell (PEM 연료전지 경량화를 위한 마그네슘 분리판의 성능평가)

  • Park, To-Soon;Lee, Dong-Woo;Kim, Kyung-Hwan;Kwon, Se-Jin
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.40 no.12
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    • pp.1063-1069
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    • 2012
  • In present paper, we used magnesium alloy having a lower density and higher electrical conductivity for bipolar plate to reduce the weight of PEM fuel cell. The silver was coated to prevent corrosion and form passivation film on the metal surface with sputtering. In acid proof evaluation for setting optimal coating conditions, the homogeneity of coating thickness was improved by coating with the thickness of 3 ${\mu}m$ which not indicated any micro cracks and the temperature $180^{\circ}C$. The performance test and evaluation based on the clamping pressure and channel depth to determine the configuration of bipolar plate for assembling single cell was implemented. And then we assembled single cell with this bipolar plate and implemented the performance test to ensure and compare the current-voltage performance followed as several factors such as coating or non-coating, the change of clamping pressure, the change of channel depth, etc. As these results, the maximum power density of single cell with the coated bipolar plate was 192 $mW/cm^2$ and it was confirmed that the power density per unit mass was better than existing metal bipolar plate.

Effect of SUS316L Bipolar Plate Corrosion on Contact Resistance and PEMFC Performance (SUS316L 분리판 부식에 의한 접촉저항 및 고분자전해질 연료전지 성능에 미치는 영향)

  • Kim, Junseob;Kim, Junbom
    • Applied Chemistry for Engineering
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    • v.32 no.6
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    • pp.664-670
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    • 2021
  • Stainless steel was applied as bipolar plate (BP) of polymer electrolyte membrane fuel cell (PEMFC) due to high mechanical strength, electrical conductivity, and good machinability. However, stainless steel was corroded and increased contact resistance resulting PEMFC performance decrease. Although the corrosion resistance could be improved by surface treatment such as noble metal coating, there is a disadvantage of cost increase. The stainless steel corrosion behavior and passive layer influence on PEMFC performance should be studied to improve durability and economics of metal bipolar plate. In this study, SUS316L bipolar plate of 25 cm2 active area was manufactured, and experiments were conducted for corrosion behavior at an anode and cathode. The influence of SUS316L BP corrosion on fuel cell performance was measured using the polarization curve, impedance, and contact resistance. The metal ion concentration in drained water was analyzed during fuel cell operation with SUS316L BP. It was confirmed that the corrosion occurs more severely at the anode than at the cathode for SUS316L BP. The contact resistance was increased due to the passivation of SUS316L during fuel cell operation, and metal ions continuously dissolved even after the passive layer formation.