in 2016 a Samsung phone started overheating in a man's pocket and ended up actually exploding causing second degree burns on the man's leg and this happened because the battery's casing was made too small on this particular model it caused the electrodes inside to bend and make contact with each other this led to a short circuit which eventually made the battery overheat and this created a cycle of chemical reactions that continually generated more and more heat until the phone eventually exploded