Multilayer Coating for Aluminium Plates in Polymer Electrolyte Fuel Cells

摘要

Portable power systems up to 100 watts, including for example chargers for outdoor applications have to meet stringent requirements regarding volumetric as well as gravimetric power density. Bipolar plates constitute the main share of the total stack weight, volume and costs. Aluminium as bipolar plate material is one of the most attractive metals among all other metallic-based alternatives, due to its light weight, its high mechanic strength as well as its low electric bulk resistance. However, one major disadvantage can be found in the low corrosion resistance of this material. The goal of this study is the development of a multi-layered coating for the surface of aluminium by physical vapour deposition (PVD) which exhibits high electrical conductivity and corrosion resistance. The coatings were analysed with the help of electrochemical methods as linear sweep voltammetrie (LSV) (Figure 1) as well as an in-house contact resistance measurement apparatus.