STUDY OF THERMODYNAMIC PROCESSES IN ENERGY STORAGE SYSTEMS, SUCH AS BATTERIES, SUPERCAPACITORS, AND THERMAL STORAGE

Abstract

This study presents a comprehensive thermodynamic analysis of three major energy storage systems: lithium-ion batteries, electrochemical supercapacitors, and thermal energy storage (TES) technologies. Utilizing a mixed-methods experimental approach combining empirical measurement, theoretical modeling, and statistical visualization, the research evaluates entropy generation, heat loss, energy efficiency, and voltage behavior across 20 operational cycles. The results indicate that supercapacitors consistently achieve the highest average efficiency (>90%) with minimal entropy production and voltage degradation, making them ideal for high-frequency, short-duration applications. Lithium-ion batteries demonstrate higher energy densities but exhibit efficiency decay and significant thermal vulnerability under increasing operational temperatures. TES systems, on the other hand, reveal robust long-term energy retention capabilities due to phase change material properties, though they exhibit greater entropy fluctuation and lower response agility. Correlation heatmaps and power distribution plots further highlight temperature-efficiency trade-offs and cumulative energy retention dynamics unique to each system. Statistical analysis confirms a strong inverse relationship between temperature and efficiency in batteries and a narrow variance in voltage distribution for supercapacitors. These findings support a hybrid energy storage strategy, where the integration of multiple systems optimizes thermodynamic performance based on application-specific demands. This study reinforces the imperative to approach energy storage not solely through electrical or material perspectives but through a unified thermodynamic framework to enhance system resilience, efficiency, and sustainability in modern energy infrastructures.