In most urban situations, the cell phone is the ultimate survival tool. With it, you can call for help, get directions, and look up practical information (you’ve downloaded a digital survival library, right?). In the wilderness, if your phone’s signal is faint or non-existent, it’s a significantly less useful tool, but can still come in handy as a lightweight camera, a basic GPS unit, and if you’re lucky, even a way to send a SOS message. In many cases however, a phone’s most useful functions are ironically unavailable in true survival situations. But, that doesn’t mean your favorite handheld device can’t get you out of a jam.
Inside your phone, a powerful lithium-ion battery has the potential to spark a fire if you know how to harness its potential. Keep in mind, taking your phone apart and using the battery to start a fire is likely to ruin it, so think carefully about whether you want to trade the potential for a signal for the chance at a fire. Also, remember that even after your battery is too low to run your phone, it likely still has enough power to spark a fire.
Finally, if the below methods fail, there is one final possible solution: Puncturing your battery with a knife or sharp object can release toxic and highly flammable gas that is likely to cause the battery to ignite and even explode. If it’s your last resort, cover your nose and mouth with a cloth, and your eyes with glasses if possible, and then puncture the battery quickly. Once punctured, set your tinder bundle on top and step away until the battery has ceased releasing toxic fumes.
(via The Art of Manliness)