That's funny Jon,...
I actually had one puff and catch on fire several years ago on a foamie after flying. I was on the way home and had them (LIPO's) in a ceramic bowl in the truck. I pulled over a threw it out the window and watched it go boom! So,..it is possible,..but not very common as it was the only pack I had to ever do it to that extent.
It sounds more like an FAA issue with regards to transportation and safety.
Regards,
Bill Holsten
Advantage Hobby & Fliton Field Rep, Duralite Batteries, Custom Airframes of America, Dragon Fire Customs, Guardian America.