Recent developments in phase change materials for energy storage applications: A review

In order to overcome the increasing demand–supply energy gap due to the rapid urbanization, labor productivity, consumerism and depletion of fossil fuel resources, there is a need for the development of technologies with renewable energy sources. Phase change materials are one of the most appropriate materials for effective utilization of thermal energy from the renewable energy resources. As evident from the literature, development of phase change materials is one of the most active research fields for thermal energy storage with higher efficiency. This review focuses on the application of various phase change materials based on their thermophysical properties. In particular, the melting point, thermal energy storage density and thermal conductivity of the organic, inorganic and eutectic phase change materials are the major selection criteria for various thermal energy storage applications with a wider operating temperature range. The strategy adopted in improving the thermal energy storage characteristics of the phase change materials through encapsulation as well as nanomaterials additives, are discussed in detail. Specifically, the future research trends in the encapsulation and nanomaterials are also highlighted.