Engineering. Searching for a better thermal battery

Energy storage has mainly focused on electrochemical systems (1). However, more than 90% of the world's primary energy generation is consumed or wasted thermally. Thermal energy storage has a broad and critical role to play in making energy use more sustainable for heating and cooling, solar energy harvesting, and other applications. Thermal storage technologies are still based on solutions developed decades ago, such as molten salt, ice, and paraffin phase-change systems, whose performance and cost do not merit widerscale adoption. Progress in materials science, chemistry, and engineering may lead to dramatic breakthroughs in thermal energy storage that could improve the efficiency with which we produce, distribute, and consume energy.