I had a dig around, you are right that transport of lithium is relatively negligible in the energy budget (back of an envelope calculations suggest around 0.5 kwh for a 1 kwh capacity battery), transport of other material such as nickel is actually more important, but even when you add them all together it is only maybe a couple of percent or so of the energy involved.

It seems that the drying process is the one to target as it accounts for around 50% of the energy budget and uses big electric ovens. Electric ovens are something that respond very well to economies of scale though, given the losses are a function of the volume versus the surface area, so you could see significant reductions there with a factory this size.