The batteries would not be Li-ion NMC cells, but more likely Li-ion LFP cells. The latter use iron and phosphate, both of which are available in very large amounts. Availability of other chemistries (like Na-ion) would only ease any constraints.

Batteries would best be used for diurnal leveling; don't overestimate demand by assuming they are used for (say) seasonal leveling.

The batteries used by electrified motor vehicles would exceed those needed for the grid.