The power density and thermal efficiency of the electrochemical Brayton cycle (EBC) have been addressed through the conservation of energy. However, it remains a gap to determine the energy density of charging and discharging processes, a crucial aspect tied to energy storage/release density in EBC systems with integrated energy storage. This study derives the energy storage/release density and net energy density of the ideal EBC system, confirming key parameters including the change in state of charge Î”SOC and the dimensionless figure of merit Î±qv/cv (Î±: temperature coefficient, qv: specific charge, cv: specific heat) are confirmed. The theoretical energy storage/ release density approximates 10 W h L-1, and the net energy density is expected to reach 1.0 W h L-1. This study provides a valuable framework for assessing the energy storage performance of EBC systems.
Keywords energy storage, energy density, electrochemical Brayton cycle, thermodynamic cycle, electrochemical heat engine, flow battery