eCig users come in various types. There is a popular craze among vapers who try various mods (modifications). Experimentation can be fun but also has risks. Here is a great piece done by Steve Vape (very good ecig blogger who seems to focus on mods and their ever-intriguing innovations).
http://www.stevevape.com/colorado-e-cigarette-explosion-lawsuit/
The problem was in the battery and are not really designed for this safety aspect. Seems the ecig user did not understand the risks behind using a modified eCig battery. Worse – it would seem that the manufacturer also did not understand the risks properly. Though the product was used as intended by the manufacturer the result was an explosion and a lawsuit. God Bless America.