Safe, fast-charging lithium battery handles five times the current

You can already charge some lithium batteries at 5x, though they don’t get good cycle life when you do so. The article does not mention the cycle life, so its hard to compare with conventional techniques.

Is there nothing carbon nanotubes can't improve?

I just build a quadcopter lithium ion batteries are great but also still terrible.

So, battery-breakthrough news is back at pre-COVID level. Which is nice.