alt Hacker NewsThe main benefits are that Sodium is abundant, cheap and stores 30x the energy of Lithium per unit mass. The draw back is that when exposed to water it explodes with 30x the energy of Lithium. The other drawback is that it bursts into flame when exposed to air.
Think of it this way, Sodium metal is abundant and cheap with 30x the energy storage (and energy transfer) of other solutions yet nobody has used it in almost any product ever (including as a coolant). The volatility of Sodium is why. Unless they have a solution to this, then I would be shorting whoever is insuring these batteries.
Sodium ion batteries use sodium ions, like in table salt. They correctly are not named metallic sodium batteries. They are less fire prone than lithium batteries, even in locations containing air.
You should also consider shorting Morton [0]. They sell sodium, combined with chlorine, one of the nastiest elements around! And for products that go in people's homes! On food!
[0] https://www.mortonsalt.com/