Characterization of CaCl2 in Mesoporous Silica as a Thermochemical Material for Energy Storage Applications

Student’s Name: Karim Haddad Home Institution: University of Alabama at Birmingham NNCI site: SENIC @ The Georgia Institute of Technology REU Principal Investigator: Dr. Akanksha Menon – Woodruff School of Mechanical Engineering, The Georgia Institute of Technology REU Mentor: Erik Barbosa – Woodruff School of Mechanical Engineering, The Georgia Institute of Technology Abstract: The building sector accounts for a third of the total energy consumption in the United States, of which 60% is utilized in space and water heating. Thermal energy storage (TES) is one of the “five thermal energy grand challenges for decarbonization” as it has the potential to be low cost, can be implemented at large scales (kW – GW), and can store energy across different time scales (hourly to seasonal) to match the supply and demand. Thermochemical materials (TCMs) in the form of salt hydrates that undergo an endothermic dehydration reaction (charging) and an exothermic hydration reaction (discharging) are promising materials for a reversible solid-gas thermal battery. This project focuses on characterizing the microstructure and properties of pure calcium chloride (CaCl2) salt and pure EV 26 (silica), specifically their porous composite with varying weight percentages of CaCl2 in EV 26, to evaluate their performance as thermal battery materials. CaCl2 is of particular interest due to its high sorption abilities and high energy density which make it an efficient medium for storing and releasing thermal energy. However, due to some of its limitations, porous silica is being added as a support matrix to improve its hygroscopic stability. Through this research, we aim to enhance the understanding and application of these materials in TES systems, contributing to more efficient and sustainable energy usage in the building sector and in other ecological engineering applications.