Sodium-ion battery

These rechargeable batteries operate by transporting sodium ions from the negative electrode to the positive electrode during discharge and back when charging. They are similar to lithium-ion batteries, but utilize sodium instead of lithium. With an energy density of 250–375 W·h/L, a nominal cell voltage of 3.2-3.6 V, and a specific energy of 0.27-0.72 MJ/kg, they can endure thousands of cycles.