Phase change materials (PCMs) for thermal energy storage systems

The development of new energy storage systems is paramount in pursuing a circular economy and reducing the carbon footprint while increasing energy efficiency. To enable these systems to offer flexibility and create opportunities through the use of new technologies, it is necessary to address the challenge of significantly low heat transfer that occurs when storing and extracting energy from integrated phase change materials (PCM). PCMs offer dual benefits by not only storing energy but also delivering substantial cooling potential, emphasizing the importance of their efficient utilization. Through phase transitions, PCMs exhibit unique capabilities for effective thermal energy storage. Both organic and inorganic PCMs are recyclable, enhancing their environmental sustainability. Their recyclability mitigates waste generation and minimizes the environmental impact associated with disposal. This attribute positions PCMs as a sustainable solution for thermal energy storage systems, promoting energy efficiency while aligning with eco-conscious practices. That makes them stand out as an attractive option among the available technologies. Hence, there is a compelling need to invest in the research and development of new PCM materials to significantly enhance the efficiency, productivity, and environmental friendliness of energy storage systems. Novel PCMs can play a crucial role in overcoming the challenges related to heat management, energy storage, and environmental sustainability. This paper presents a comprehensive review of recent advances in improving the thermal conductivity and thermodynamic properties of PCMs for thermal energy storage, as well as an analysis of energy storage in systems in which PCMs have been employed. This review provides a comprehensive analysis of the inherent thermodynamic and thermophysical properties of PCMs and their applications in thermal energy storage and management from detailed experimental and theoretical perspectives, addressing a gap in the literature. Furthermore, a suitable criterion for ideal PCMs is presented. In concluding remarks, we explore how PCMs serve as a pivotal solution for mitigating renewable energy unpredictability while simultaneously advancing the ideals of the circular economy (reduce, reuse, and recycle).