Contamination assessment in metal foam flow field-based proton exchange membrane fuel cell

The relative slippage between the open-cell metal foam flow fields and other parts in a fuel cell due to vehicular and flow-induced vibrations causes fretting. The material degradation due to fretting in nickel struts contaminate the stack and is investigated using simulated experiments. The as-formed strut surfaces are rough and increases the material loss during fretting. The total wear volume associated with a single contact in 22,000 cycles is 4.66 E-04 mm(3). The contamination in the stack is estimated assuming a dodecahedron unit cell geometry and neglecting the fretting corrosion. About 47 g of debris is expected to be generated when an 8 ppi nickel foam flow fields used in a 50-cell stack for 8700 hours of operation. In addition, the generated flake shaped debris (<10 mu m) can obstruct the flow of gases by clogging the gas diffusion layer. The proposed contamination estimation methodology will aid in performance prediction during service. (C) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Automated summary

Slippage caused by vehicular and flow-induced vibrations can lead to fretting and contamination between the open-cell metal foam flow fields and other parts in a fuel cell, which may affect the performance.