It's not even just a QA thing, consider the use case: A sub-ohm vape head is basically almost shorting what is often a unprotected lithium ion cell (18650 or whatnot). Phones meanwhile are full of temperature sensors, battery pack in the phone has some kind of firmware/monitoring, board on the phone has a charge controller.

There are plenty of good cell manufacturers that won't have problems in this current dumping situation (and will have certain passive protections like a CID to cut the current if it gets too hot). Problem is people like cheap and there are sketchy knockoff cells without those protections and shoddy manufacturing quality.

If there was anything recently that forced the change it was probably the CT scans of the Haribo battery packs showing the cathode/anode overlap. This sort of thing should spook airlines.

Do we still have UL? Do they test battery packs? Why not make it a requirement to only fly with ones that pass lab testing like UL?

You’re both saying the same thing.