Novel coatings deposited by modulated pulsed power magnetron sputtering for PEM fuel cell and electrolyser bipolar plates

In order to be able to take full advantage of intermittent renewable energy sources, the energy needs to be stored. This energy can be stored as hydrogen, and later be converted to energy in fuel cells. The desired way to produce hydrogen is by water electrolysis, and the most energy efficient system is the polymer electrolyte membrane (PEM) electrolyser. Likewise, polymer electrolyte membrane fuel cell (PEMFC) is of great interest as a clean energy device to produce electricity from hydrogen with water as the only by-product. Due to its lightweight and high efficiency, PEMFC are ideal for transport applications. 

Bipolar plates (BPP) are crucial components in these devices. BPPs are exposed to acidic environment, but also must withstand high overvoltage in the anodic side (2 V) and cathodic side (1.4 V) of the PEM electrolyser and fuel cell, respectively.

In this study, different multilayer coatings deposited by modulated pulsed power magnetron sputtering (MPPMS) on titanium and stainless steel BPP are investigated. The coatings must be high corrosion resistant and electrically conductive in PEM environment.

Ex-situ electrochemical tests and interfacial contact resistance (ICR) measurements were conducted in PEM environment to evaluate the performance of these coatings for enhanced durability of BPP.