Researchers at Nokia and Queen Mary University in London believe they have a novel solution to smartphone battery limitations: Instead of trying to improve the battery itself, they've figured out how to keep it charged through sound waves.
The key, according to Gizmag, is the use of zinc oxide, whose piezoelectric properties can generate an electrical current from mechanical stress. The researchers started by spraying zinc oxide onto a plastic sheet and heating it in a chemical mixture, creating an array of zinc oxide "nanorods."
The nanorod sheet bends in response to sound waves, creating enough mechanical stress to generate electricity. Researchers then sandwiched the sheet between layers of aluminum foil to harvest the voltage.
On a prototype device roughly the size of Nokia's Lumia 925, the researchers were able to generate up to five volts from background noise such as traffic, music and voices. They claim that's enough help charge a phone, though it's not clear to what extent.
It's easy to get excited about these kinds of developments, but keep mind that success in a university lab is a poor indicator of future products. For years, we've been hearing about amazing battery research, from the ability to charge electronics with a heartbeat to instant charging technology to entirely new battery chemistry, but none of these advancements have appeared in actual phones that you can buy today. Many of them must address significant hurdles around design, cost, manufacturing and safety before they become practical for the market.
In other words, you'll have many more realistic reasons to scream at your phone for the foreseeable future.