There are no such statistics available that I am aware of. The below study comes to an anecdotal conclusion that the recent popularity of sub--ohm vaping and mods with removable batteries has resulted in e-cigs explosions which are more likely to explode during use and far more likely to cause serious injuries than in the past.
E-Cigarette Explosions: Comprehensive List
There have been 50 major incidents this year (2016) alone and that's just the ones which make the news. They also go on to say...
"It is interesting to note that the nature of e-cigarette explosions has changed over the years. The FEMA document cited above suggests that approximately 80 percent of e-cigarette explosions happen during charging. In addition, most e-cigarette explosions that occurred before early 2015 involved no reported injuries. However, people began to experience different types of e-cigarette explosions when sub-ohm vaping and mods with removable batteries became more popular. More than ever, e-cigarettes explode during use. Explosions resulting from people carrying spare batteries in their pockets are also far more common. Regardless of the circumstances, e-cigarette explosions are far more likely to cause injuries today than they were in the past."Tobacco Truth: E-Cigarette Battery Hazards Minuscule and Overblown
I personally believe that we don't read about mech squonker explosions compared to tube mechs is because mech squonkers are arguably less common and are not as popular with the younger male population of cloud chasers. In addition, most squonkers are box mods that have just a magnetic battery door which allows the gas pressure from a venting battery to blow it away or escape via the hole for the squonker's liquid bottle.
Thermal runaway is a relatively rare event. Venting batteries are more common. Venting batteries may cause burns if the user is holding the mod, but if the gas has an escape route it shouldn't cause the mod itself to explode. A tube mech is most likely to explode if there is no adequate vent route.
The below statements were made by our former ECF manager and battery expert,
@rolygate:
"- Sealed metal tubes will probably explode if a battery vents violently
- The battery itself may physically block gas from escaping to the bottom of the mod
- Small vents at the bottom of the tube are useless, only very large gas vents near the top have a good chance of preventing an explosion
- Building coils lower than 0.2 ohm will raise the amp draw exponentially and this increases risk - the power graph shows a significant change at 0.2 ohms and starts to climb vertically as resistance is reduced further
1.0 ohm = 4.2 amp draw
0.9 ohm = 4.6 amp draw
0.8 ohm = 5.2 amp draw
0.7 ohms = 6 amp draw
0.6 ohms = 7 amp draw
0.5 ohms = 8.4 amp draw
0.4 ohms = 10.5 amp draw
0.3 ohms = 14.0 amp draw
0.2 ohms = 21.0 amp draw
0.14 ohms = 30 amp draw
0.1 ohms = 42.0 amp draw
0.0 ohms = dead short = battery vents or goes into thermal runaway
-
Using cheap batteries with ultra low res coils is a certain route to high risk - it needs 30 amp batteries of guaranteed high quality
- Using long draws or machine-gun draws to create monster clouds stresses the battery much more
- Cloud Contests are events where people put ultra high stress on their rig to create monster clouds; if spectating, you could consider standing at the back of the room to stay safe
- If you run a Cloud Contest then you should probably check that your personal and business insurance is really, really good and is appropriate for dangerous sports
- People are now discussing the safety (!) involved with putting 100-amp pulses on their batteries in order to create the biggest clouds with the lowest resistance coils; there is only one way this is going to go and you don't want to be within the explosion radius: someone may have a counterfeit battery, or one that is just too small for this extreme usage mode together with ignoring the device getting warm or even hot."
