I disagree with directly comparing "all-in Li-ion battery cost"...

I disagree with directly comparing "all-in Li-ion battery cost" with cost of V (see below). But agree that things are in flux regarding viability of VRBs. As far as I can see, there are a few things going on.

First, recycle/reuse economics for VRBs are quite different from Lithium battery recycle/reuse. Vanadium electrolyte in VRBs does not degrade over time. Lithium batteries degrade with use. Hence talk of leasing V electrolyte.

Second, the Vanadium price has spiked. But will it stay this high? In the past, Vince has said that he expected the Vanadium price to stabilise at a much lower level that the current one. If the V price does "normalise" then the economics for VRBs will improve. That said, if there is some kind of critical time window for technology adoption, this could disadvantage VRBs long-term.

Third, the main markets for Lithium batteries vs VRBs are distinct. The narrative a year or two ago was that Lithium batteries would be for lower capacity and/or faster response-time, while VRBs would be more suited to larger, long-term base-load storage -- this reflects the natural technical capabilities of each technology. However, even back then there was talk that the economies of scale for Lithium batteries might allow them to move into the VRB-suited markets. Personally, I think the jury is still out on this dynamic, especially for high-end infrastructure scale storage (I'm thinking Ronke Dalian scale and up here, not Hornsdale scale load-balancing).

Finally, in recent times, AVL are clearly viewing Steel manufacturing as the the main game. While VRBs are a potential speculative opportunity, AVL is not betting the house on it -- that's gotta tell you something.

Just my two cents. I'll be interested to hear what others think.