Before you watch this video I strongly recommend you do not try this at home. In this video, a guy takes out the battery from his cell phone and then decides to stab it a few times with a knife. What happens next is really disturbing. After three pokes with his knife the battery literally starts catching on fire then erupts to a serious fire that really has to be seen to be believed.

Most cell phones today use a battery technology called lithium ion.

Lithium-ion batteries are common in consumer electronics. They are one of the most popular types of rechargeable batteries for portable electronics with a high energy density, no memory effect, and only a slow loss of charge when not in use. Beyond consumer electronics, lithium-ion batteries are also growing in popularity for military, electric vehicle and aerospace applications.

Lithium-ion batteries can be dangerous under some conditions and can pose a safety hazard since they contain, unlike other rechargeable batteries, a flammable electrolyte and are also kept pressurized. Because of this, the testing standards for these batteries are more stringent than those for acid-electrolyte batteries, requiring both a broader range of test conditions and additional battery-specific tests. This is in response to reported accidents and failures, and there have been battery-related recalls by some companies.

After seeing this video you might want to treat your phone more like it is a dangerous bomb, and less like something you want to throw across the room.

(via wikipedia)