Ann: Altech - Breakthrough Silicon Alumina Coating Development, page-219

Scalable Synthesis of Nano-Silicon from Beach Sand for Long Cycle Life Li-ion Batteries

I'm trying to figure out where ATC will get the raw material for their Anode mix.

They have the High Purity Alumina process sorted which will use kaolin from Meckering.
Graphite I don't know yet.
Silicon I would imagine needs to be high grade so I know how PV silicon is made, semi conductors are made, even about a company called 1366 technologies who melt then form their silicon from the liquid.
But they are all energy intensive processes & would not give the 150nm scale Silicon without milling, adding even more energy.
So if the Silicon which ATC are planning on using comes from "beach sand" well really good quality sand, that they have access to an improved process that ticks ESG criteria, then this IMO is very encouraging.