> 160Wh is 160Wh.

And yet you can carry a 100Wh spare battery and a 100Wh laptop and a 15Wh cell phone...

Ultimately, an 80Wh battery and a 160Wh battery both have more than enough energy for overheating to start a serious fire. The much more important consideration is the quality of the battery controller and the physical protections on and within the battery. And it's also important that many planes now carry burn bags that they can quickly put a runaway overheating battery (or phone or other device) into.

It would make more sense to have a battery certification and require batteries to have that certification in order to carry them on a plane.