You'd need to be able to store WEEKS of electricity to make wind+solar work.

Currently, battery grid-scale storage stores seconds.

You'd need an increase of several orders of magnitude for this to work.

Even if manufacturing costs were magically 0, the amount of lithium, copper and other materials required would be unsustainable.

It's not going to happen.

Do you realise that German government, European Union and independent third parties have all published scientific estimates as to how much storage is needed and no, it’s not for weeks?

You don’t use lithium for long term energy storage. You just have very shallow understanding of issues at hand.

Do you have any source elaborating on that?