Polypropylene Compounds for PEM-Electrolyzer Plates: Materials, Processing Methods, and Analysis of the Materials

Abstract

Titanium and graphite-filled composites together with a polymer, such as polypropylene, are a suitable material for bipolar plates in PEM electrolyser applications. Similar to pure titanium metals, titaninium and graphite composite plates have quite good properties when mixed with polypropylene (PP). The plates have relatively low electrical resistance and can withstand the aggressive electrochemical environment encountered in an electrolyser. The main challenges here are resistance to oxygen, hydrogen, and complete. The conditions in operation are extreme. Above all, the comparatively high voltage and the fact that pure water is used generally cause problems for the materials. Besides pure titanium, composite materials can also be used. This chapter summarizes the most important requirements for the titanium-PP composite material. This material is used for bipolar plates. This is the basis for the characterization methods of titanium-based bipolar plates. The modern PP-based composites and their general properties are described, with a focus on improved long-term stability. In this chapter, the material fillers such as titanium and graphitic powders are analysed. The last deals with the way the electrical conductivity of the materials is measured and with in situ operation.