Lithium ion batteries like those that power the Samsung note 7 are one of the biggest issues in aviation safety right now. They are prone to spontaneously catching fire when overheated and it's often really hot on the ramp areas of airports. Once on fire they're very hard to put out, especially in the confines of a cargo hold with no crew access. UPS had a 747 crash in Dubai back in 2010 that was the result of lithium ion batteries that caught fire.
Lithium ion batteries power almost every electronic device out there nowadays so banning them on aircraft is impossible. I'm a pilot for a cargo airline and carry them all the time. We have certain procedures for handling them and they're only allowed in certain places on the aircraft to help mitigate the risks. They still concern me more than almost any other safety issue right now. Lithium ion batteries worry me much more than terrorism to be honest.
