Smells like the usual blather. I'm not even gonna watch it.
CATL or some other company will eventually make a significantly better battery. I equate significantly to >40% existing energy density.
Until it's on the street in a production vehicle, I take all battery claims with a healthy dose of skepticism.
Where Musk is concerned, the BS meter is usually off the end.
Even after it's on the street, it needs end-user validation. Remember that laptops and cellphones would occasionally burst into flames. More recently, Chevy Bolts would occasionally burst into flames. (Things got better.)
Sagan's standard: Extraordinary claims require extraordinary proof.