True, but this is solid state so it may be higher density than current Lithium based batteries. But it might not beat a hypothetical lithium solid state battery. On the other hand, sodium batteries today beat out lithium in many other ways than capacity, and if those things are true for solid state then as long as there is a big enough jump in capacity due to the solid state transition then I think sodium is going to be the go-to for most uses in the future.