Here's the thing. A Lithium-ion battery stories a lot of power for its size. That's why they're so popular and now fit in all sorts of things - from cameras to so-called hover boards, from DECT phones to torches, from LED lights to, apparently, the kind of things lonely ladies use to brighten their evenings.
Here's another thing. They really don't like delivering more power than they're rated for. In other words, if you short them out by - oh, I dunno - dropping a fully charged "spare" in a pocket full of change and keys, they have this tendency to, as our friends in the press like to put it, EXPLODE!
In a device - let's say an ecig, or a camera, or (sorry) one of those devices ladies use to make their evenings a little more enjoyable, they're a whole host less likely to, you know, EXPLODE! Have we heard of a lady having her bits rendered mincemeat by a lithium-ion battery going postal while wobulating? No! Would we? Probably not. Has it happened? Almost certainly. But the papers don't report that. Why? Probably because a lady is unlikely to to want the publicity surrounding such an occurrence. Would the papers pay handsomely for such a story? Hell yeah! Are they going to get one? Hell no!
And yet, they keep digging up stories about numpties who drop a spare, fully charged, very powerful Li-ion battery in a pocket full of change and then wonder why it's gone boom and rendered their leg only slightly less cooked than a fillet steak on a cookery competition. AND THEY PAY THE NUMPTIES FOR THE STORY.
Agenda much? Torch batteries go boom, laptop batteries go boom, camera batteries go boom, vibrator batteries go boom - nothing. Not a peep. A vaper makes a battery go boom, and it's everywhere.