How to improve the potential of high-temperature thermal energy storage technologies through ceramic matrix composites

Kurzfassung

The significant increase of world energy consumption raises the demand for imperatively clean energy resources. Since energy production methods have been greatly improved, one of the biggest challenges remains the development of high-performance energy storage systems. In this work, two newly developed thermal storage concepts with different storage materials, metallic phase change materials (mPCM) and molten chloride salts are investigated. Due to their unavoidable corrosion aggressiveness at high temperatures (HT), Ceramic Matrix Composites (CMCs) are used as housing material as they are well known for their high mechanical properties and HT damage tolerance. The compatibility between storage materials (mPCM and molten chlorides) and Liquid Silicon Infiltration based carbon fiber reinforced silicon carbide (C/C-SiC) composite has been firstly investigated via contact angle measurements. Then, C/C-SiC coupons were immersed separately in molten chloride salt and liquid mPCM at 700°C for several hundred hours. The results reveal that the C/C-SiC composite maintains its material properties after exposure in the both strongly corrosive storage materials. It is shown that the applicability of different thermal energy storage technologies at HT can be improved through C/C-SiC composite due to its excellent corrosion resistance and favorable material properties at HT.