Is it possible? Yes. Is it likely? Not if you follow basic rules of battery safety. I just went to a great class on the subject at DC Vapefest. A few of their key points: buy the best quality batteries available, don't store them loose in your pocket or purse or junk drawer where they can short out on other metal objects, let them rest about half an hour after taking them off the charger, and, if you see any damage to a battery, don't use it. Get a good quality charger, and don't leave the battery on the charger overnight. And realize that no battery lasts forever. (props to Zen and Neil Helland for this information).