Total global battery production seems to be 200-300GWh/year. If you want to buy approx 30% of total yearly output it's very unlikely you can negotiate your way to the head of the line. In fact, buying that much might raise global prices for batteries.

If I want enough solar panels and batteries to make my house off grid I can just write a check and the stuff shows up in a few weeks. But that doesn't scale upwards without limit. Eventually the limits on global supply kick in no matter how much you want it.

Nobody said the installation had to happen overnight. A five year plan would be impressive and still feasible.