A:Answer Well....this is sort of true but not entirely true.
You cannot put a Lithium battery in your checked luggage. It can catch fire in the unpressurized luggage cabin at high altitudes and while the oxygen levels at 35-40,000 feet are much lower than at ground level, there still is some oxygen and it could potentially cause a fire to spread throughout that compartment and jeopardize the plane.
However, you can bring it in your carry-on bag or your pocket into the pressurized cabin. I suppose there becomes some risk if the cabin becomes depressurized, but this is an extremely rare occurance, and all of the cell phones that are in the cabin as well would pose a similar risk, so you're fine.
](https://pisces.bbystatic.com/image2/BestBuy_US/images/products/fadf93d1-f078-49da-a272-0f01f4ce8a54.jpg)
