Researchers have developed a cost effective and efficient thermal energy storage material that can improve the performance of thermal batteries used in concentrated solar power plants and for industrial waste heat recovery. The work was carried out at the International Advanced Research Centre for Powder Metallurgy and New Materials (ARCI), an autonomous institution of the Department of Science and Technology (DST), which developed a scalable process to produce spinel nanocomposite phase change material (PCM) with an unprecedented increase in specific heat capacity. The research has been published in Materials Today Chemistry and is presented as aligning with India’s clean energy objectives and the Aatma Nirbhar Bharat initiative.

The ARCI team led by Dr Mani Karthik employed a simple co-precipitation method to produce spinel type metal oxide nanoparticles with controlled particle size and uniform dispersion, yielding materials with excellent thermal stability. These nanomaterials are suitable for producing high performance nanocomposite PCM because they increase specific surface area and promote the formation of a stable spinel oxide layer at the interface. The interfacial layer is reported to raise surface energy, which contributes to the nanocomposite's higher specific heat capacity compared with the base PCM.

The addition of only one per cent spinel oxide nanoparticles to the PCM produced a nanocomposite that showed an increase in specific heat capacity as high as 45 per cent relative to the base material. As a result the material can store more thermal energy per unit mass, improving overall energy storage efficiency within a given volume. Enhanced storage capacity enables smaller tanks and reduced material requirements, which lowers both capital expenditure and operational costs.

The development therefore offers a compact and cost effective thermal energy storage solution that could support next generation systems with superior performance. The scalable production route and the demonstrated property enhancements make the material applicable to concentrated solar power and industrial heat recovery applications where effective thermal energy storage systems are essential. Further adoption is positioned as advancing indigenous capabilities in energy storage material science.