Performance and degradation analysis of sodium-ion battery integrated with solar photovoltaic system for microgrid applications

Abstract

There has been tremendous growth in renewable energy harvesting techniques, which has played a crucial role in combating the global climate crisis. Energy storage devices are required for effectively harnessing these intermittent renewable energy resources. Sodium-ion batteries are one of the next-generation energy storage devices being reassessed for commercial applications due to their abundant resources. This study integrates a solar photovoltaic system with a sodium-ion battery for load management in microgrid applications. The analysis is performed on sodium-ion batteries designed for 1, 1.5, and 2 autonomy days, having different initial states of charge and microgrid operation starting months. The reliability of the microgrid system is assessed based on the loss of load factor. The analysis utilises real-world hourly data accounting for seasonal load fluctuations and incorporates a power control strategy to manage load demand efficiently. Physics-based electrochemical and degradation models are implemented to capture the internal dynamics and capacity fade caused by the solid electrolyte interface layer formation and sodium plating. Simulation results show that a battery designed for 1.5 autonomy days performs comparatively better, with a capacity and sodium inventory loss of 3.36 % and 2.21 %, respectively. This study provides an understanding of the long-term battery performance and degradation under various operating conditions and contributes to advancing the microgrid's performance.