Sodium Resistance of Ceramic and Glass Materials - Na Thermo-gravimetric Analysis and Liquid Na Exposure Test

Abstract

Renewable intermittent energy sources like solar and wind power are important for decarbonizing the energy sector and energy storage will become necessary for balancing production and demand and can also be important for load levelling purposes. Such energy storage should be cheap and made from readily available materials. A suggested battery technology is the all-liquid molten salt Na-Zn battery, which is operated at 600 °C. The battery produces liquid sodium during charging. Sodium will float to the top of the electrolyte. Ceramic and glass materials which act as insulating and sealing materials tend to corrode/disintegrate in contact with liquid and/or gaseous sodium. Therefore, in this study, different ceramic and glass materials were exposed to gaseous and liquid sodium to determine their resistance to sodium integration leading to materials degradation. The samples were investigated by micro-X-ray computed tomography (µ-CT) before and after exposure. This study found that glass ceramics showed low resistance to sodium exposure, while materials such as Al2O3 and AlN showed good resistance to sodium exposure.