Researchers at Virginia Tech have developed a novel method for charging your mobile phone. Shashank Priya and his team are developing an emergency onboard charger that draws energy from piezoelectric force. A small amount of this can be generated by typing on the keypad, talking into the phone, or shaking the device, which would enable you to make a quick call or send a text in an emergency.
Zinc oxide, a piezoelectric material, could be fitted below the keys to convert vibrations from sounds and pressure waves into stored energy to power the phone. Gizmodo reports that the researchers experimented with this material by subjecting it to sound waves of 100 decibels, which caused it to produce an electrical current of around 50 millivolts.