WJLA-7 aired a report “Warning: Exploding Lithium” on the increasing attention to the remote but possibly catastrophic results from lithium battery explosions and fires, especially in electronics. In the past, entire brands of smartphones (in Samsung's lines) were banned from planes because of this problem.
And a very few lithium battery laptop fires have been reported, although these may be from a known manufacturing issue in the mid 2000’s.
The way travel works, it is critical that people be able to bring their devices (phones, tablets and laptops) on planes and have them fully usable when they arrive.
One tip is not to leave unattended devices plugged in.