A sodium battery is a type of electrochemical cell that uses sodium ions as the charge-carrying species. Sodium batteries are similar to lithium-ion batteries in that they both use ionic movement to store and release energy, but they differ in the materials that they use. Sodium is an abundant and inexpensive element, making sodium batteries a potentially attractive alternative to lithium-ion batteries for certain applications. However, sodium batteries also have some drawbacks compared to lithium-ion batteries, such as lower energy density and shorter lifetimes.