Isn't the concern with Personal laptops that with non OEM batteries, the normal thermal protections may be missing which increases the risk of themal runway if you're plugged into the aircraft power supply and/or blocking the laptops vent cooling?

The concern is with lithium ion batteries, period. Making them all go away isn't going to happen presently. Even in cases where batteries are properly packaged, or in the equipment they power, runaways and high order failures have occurred. As recently as a few days ago, in fact, a flashlight with Chinese lithium batteries, in the cockpit in a freight aircraft, caught fire.

The water in a bottle adjacent to the flashlight put out the lithium, whereas halon failed to do so. The halon did put out the burning backpack, however.

The major freight operation at which this event occurred strongly urged operators to use great caution with Chinese lithium batteries.

Several posters here have incorrectly stated that Halon is effective on a lithium fire, which it is not, and have downplayed the fire potential from lithium batteries. Elsewhere on this forum site I have posted the quote from the freight operator, addressing the recent fire. It's something to take seriously.

But the number oif such batteries in the world is HUGE, and we don't see the devices they power, if properly used and maintained, bursting into flames regularly, thus the probability of a fire actually is low and the risk neglgible.