
'Exploding e-cig cost me 7 teeth, burned my face – and broke my sink' - aceperry
http://www.theregister.co.uk/2017/01/18/explosive_ecig_broke_seven_teeth_and_sink/
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wolrah
As has to be said every time one of these stories comes around, this is not
representative of normal e-cig use.

This person had what's called a mechanical e-cig, or "mech mod". They use no
electronics, just a big switch or relay and the sometimes sub-ohm coils used
for heating the liquid.

A mech mod works by nearly short circuiting a lithium ion battery. You need to
carefully measure and build your coils to provide sufficient resistance and
only use it in short bursts. You also need to use a battery (or batteries)
capable of delivering the amperage you're asking of it (them). If you don't
follow these rules, or if something gets damaged and your device short
circuits, you're going to have an unhappy battery in your hands/pocket.

What happens when a lithium ion battery goes nuts? See article.

There have been regulated e-cigs for years with electronic controls both to
limit current and time things out if a button gets inadvertently pressed.
Those don't blow up.

Mechanical e-cigs are not for normal users. They're for the "cloud chaser"
competition types trying to be human fog machines.

You can kind of analogize mechanical e-cigs to nitrous oxide in a car. It's a
cheap way to get a lot of power but you have to use it carefully if you don't
want to blow things up.

~~~
jdietrich
Even without a battery protection circuit, this wouldn't have happened if the
device was properly vented. When li-ion cells go into thermal runaway, they
produce large quantities of gas; that only causes an explosion if the device
doesn't have sufficient venting to allow that gas to escape. If the mod had a
couple of holes in the bottom, this chap would have escaped with nothing worse
than minor burns to his hand.

This isn't a story about electronic cigarettes, but a story about people doing
astonishingly stupid things with batteries. An exploding mod is the end result
of a long chain of extremely bad decisions.

