Technology

And it’s more ethical and environmentally friendlier than Lithium-Ion, right?

The amount of metallic sodium we need for these purposes dwarfs compared to what we're using directly as NaCl, that is, table salt, not just in food but primarily industrial processes. Which again dwarfs compared to what we have available (vaguely gestures at the oceans). Sixth most abundant element in the earth's crust and conveniently most of it is in the form of huge contiguous dried-up oceans buried somewhere.

Thinking of it should become standard practice to actually use the salt that's accumulated when desalinating to get drinking water, lots of issues with locally increasing the salt level in the ocean even though on a large scale the change in salinity is absolutely negligible.