Sodium batteries (also known incorrectly as salt batteries) have gained a lot of attention from the scientific and industrial world in recent years.
The abundance and ease of finding this alkaline metal make it a top-level competitor in comparison to lithium. Furthermore, the constant commitment to performance is leading to the overcoming of some intrinsic disadvantages, such as lower capacity. The latest milestone achieved in this field belongs to Chinese research which has created a unit without anode with an energy density exceeding 200 Wh/Kg.
Integrating this technology with the use of solid electrolytes could theoretically give a further boost to energy density and improve charge-discharge cycles (a sore point for traditional sodium ion batteries).