CLEVELAND -- Stranded on the side of the road with a dead car battery and a dead cell phone? Not if you keep a 9-volt battery handy in your glove compartment.
It's possible to revive a dead cell phone by using a 9-volt battery, along with something metal like a key, and your phone's car charger.
Our own Lynna Lai tested it out.
First, plug your phone into the charger. Then, touch the metal tip of the other end of the charger to the small terminal of the battery. As you hold it in place, use a key to connect the large terminal of the battery to the metal side of the charger.
Hold everything together in place for several minutes, and you'll build up enough of a charge to power up your cell phone for an emergency call.
Using an iPhone 5, it took us about seven minutes to go from a dead battery, to a two percent charge.
It's not clear, though, whether frequent use of this method will do any damage to the phone's battery. After several tests we did not see any noticeable wear to our iPhone. However, in an emergency situation, this could be a potentially life-saving hack.