As the issues of depletion and exhaustion of traditional fossil energy and deterioration of the environment become increasingly severe, it is urgent to develop renewable and sustainable energy sources to alleviate the crisis of global warming and energy shortages. However, the present most serious problem of renewables is the time and space mismatch between supply and demand due to their intermittent natures. A gap between the energy supply-side and demand-side should be bridged, and it is still a challenge. Under this background, energy storage technology provides the chance to gather the surplus energy from various waving renewable and non-renewable energies independent of the demand; consequently, the temporarily available energy is transferred into permanently accessible energy.

Generally, energy storage technologies can be categorized into thermally-based energy storage, chemically-based energy storage, and electrically-based energy storage. This special issue focuses on the recent research advancements, case studies and practices to promote energy storage-related technologies and aims to provide a stage for researchers to communicate the state-of-the-art progress. Research related to energy storage technologies from the level of basic principles, materials, components and systems is all welcomed.