Acoustic charger

People who like to talk on the phone may become an energy maker in the future. The ddddof South Korean scientists is expected to convert sound waves （battery charger)into electrical energy, so that the longer the call time is, the more sufficient the battery will be.
Novelty application
South Korean scientists extract a tiny substance from calamine solution that can convert sound waves into electrical energy, thereby creating an energy plate. The board will produce acoustic energy calls into electricity, mobile phone charging, or the peak period traffic noise into electrical energy supplied to the national grid.
Study leader Pu Yongjun and American Broadcasting Company quoted Jin Xiangyu as saying, the loudspeaker to the electrical signal into sound, on the other hand, may sound into electricity.
"Sound can have many novel applications, such as the use of voice charging mobile phone, the side of the highway by the traffic sound generation soundproof wall." The report says.
Mechanical energy transfer energy
The material that can extract energy from call and incoming sound is piezoelectric. When the material is bent, mechanical energy can be transformed into electricity.
Many substances are piezoelectric, such as sucrose, quartz, and even dried bones. For decades, scientists have injected electricity into piezoelectric materials for environmental sensors, speakers and other devices.
In the past few years, scientists have tried to extract power from a piezoelectric device and make great progress. Most of the piezoelectric devices can generate electricity while walking, running and talking. The US Army even assumes that the physical impact of a bullet is converted into a weak current, but the consumer is unable to buy this device at the moment.
South Korean researchers use the main component of calamine lotion Zinc Oxide to produce a sandwiched between two electrodes of the nanowires, and then use this set of 100 dB sound wave electrode device, generating approximately 50 MV current.
Technology needs to be matured
The sound volume of the experiment is slightly smaller than that of a rock concert, and the volume of normal conversation is only 60 to 70 dB. In general, the operation of a mobile phone requires a number of volts, which are several times the power generated by this experiment.
McAlpine, a scientist at Princeton University, is also studying equipment that can get energy. He said that Korean scientists' research is interesting, "but the real question is whether there is enough environmental noise to provide mobile phone energy." Consumers may not want to join a rock concert or stand by the train to recharge the phone.
South Korean scientists agree with this view. They said that the current 50 MV is not very strong, but this study has been verified with the sound power of this concept, they will develop more output power equipment.