Lab bench to product can be 15 years or more, so doesn’t mean it doesn’t work.
The other hard thing is beating Li-Ion. It would have to be a lot better or cheaper to beat the economy of scale. Just a little better won’t displace the incumbent.
That's the thing: Lithium ion batteries are not a fixed technology, they're a moving target. They've evolved dramatically and encompass many different chemistries since they first appeared in the lab in the 70's. But since they're all grouped under the name "Lithium ion" people just think of them as a fixed, static, mature technology.
