[_hypx]

The author of that article is simply wrong. I've seen this post more than once now and it is becoming a serious mistake on their part.

FYI, high energy density li-ion batteries existed since 2009: https://news.panasonic.com/global/press/en091218-2

There is hard contradictory evidence to the claims of that DoE article.

[ProjectArcturis]

Is there a distinction between the batteries existing vs. being in mass production? A lot of the difficulty comes from scaling production processes.

[_hypx]

You figure there are cost issues related to lack of mass production. But ultimately, the chemistry is there and you can could have build something in the late 2000s or early 2010s at those higher energy densities. Certainly, any graph that goes right through 2017 and not mention these advances from 2009 would be nonsensical. It is ignoring 8+ years of preexisting technology.