Ann: CEO Presentation to the AGM, page-6

Precisely why NVX is such a safe bet, it's a supply game for the next decade or more.

This article, although focused more on natural graphite, goes some way to answer your question:

“You had up there earlier, ’97 [GRAPHITE] mines required’,” he said.
“At BlackEarth, we probably monitor closely about 15 mines around the world, probably another seven on top of that, as outliers.
“I think I’ve got a reasonable understanding of the graphite industry; where the other 80 mines are coming from, I have no idea, no idea whatsoever. So it’s got to be a supply game."

https://unauthorised investment advice/resources/caught-short-miners-say-graphite-is-poised-to-be-lithium-2-0/