You can charge a phone battery by playing music at it
he Queen Mary University of London, a group of scientists has created a prototype panel capable of charging a cellphone off environmental vibrations like music or dinner conversation.
Researchers call the device a “nanogenerator,” and it looks like a flat metal plate with some wires attached. In reality, it’s plastic sprayed with a sheet of tiny zinc oxide rods that generate electricity when squashed or stretched — as they would be in the presence of everyday background noise. The group is building off previous research that found solar cells became more efficient when exposed to acoustic vibrations, especially the high-pitched tones of pop music. This time around, there’s no solar component, just what’s known as piezoelectric energy generation. The research team, which worked in partnership with Nokia, says that these sheets can be produced cheaply and generate five volts of electricity, the same as most phone wall chargers.