Structured Multilayer Electrodes without Nafion for Polymer Electrolyte Membrane Fuel Cells

Abstract

The use of alternative support materials and special MEA preparation techniques allow a replacing of Nafion® within the electrode layer. A possible candidate for the replacement is the electron/proton conductive polymer polyaniline (PANI). This material has proven its suitability and stability as support in a fuel cell environment. The incorporation of Pt/single-walled carbon nanotubes (SWCNT) between the PANI layers can improve the electron conductivity of the system. The assembly is fabricated by the newly introduced spray coating technique, in which alternating layers of Pt/PANI or Ru/PANI, and Pt/SWCNT are sprayed directly onto a Nafion® membrane. 3D electrodes are obtained with an expected high porosity and enhanced noble metal utilization. The assembled multilayered electrodes were used at the anode side with a commercial Pt/CB-Nafion® catalyst layer at the cathode side in a real fuel cell test. The MEAs showed high Pt utilization values with an adequate power density.

Thermodynamics, Charge Transfer and Practical Considerations of Solid Boosters in Redox Flow Batteries

“…Therefore, the mechanisms in the cell are well-known [ 19 ]. Meanwhile, only very few works have studied the kinetics of charge storage in the redox solid materials with redox targeting within the tank [ 13 , 14 , 20 , 21 , 22 , 23 , 24 ]. In an attempt, Li x FePO 4 (0 ≤ x ≤ 1) was coated on a double-layer electrode with an insulating Al 2 O 3 layer and was charged and discharged with the Fc and FcBr 2 + redox couple with a biased electrode [ 20 ].…”