There are various forms of batteries, including: lithium-ion, flow, lead acid, sodium, and others designed to meet specific power and duration requirements. Initially used for consumer products, lithium-ion batteries now have a range of applications including smaller residential systems and larger systems that can. Thermal systems use heating and cooling methods to store and release energy. For example, molten salt stores solar-generated heat for use when there is. Compressed air, superconducting magnets, underground pumped storage, and hydrogen storage are all forms of emerging energy storage that are in different.