Running out of phone battery before the end of a long day is the depressing norm for most of us - but soon this problem could be gone, as a new case claims to harvest energy from radio waves to increase battery life by 30%.

Developed by Nikola labs - named after the famous scientist Nikola Tesla - the case connects to the charging socket of an iPhone 6 or Samsung Galaxy S6 and can add several extra hours of life every day by trickle charging the phone's battery with power harvested through the air.

When a smartphone is switched on it uses Bluetooth, Wi-Fi and a 3G or 4G connection to stay online, and all of these use radio waves to transfer data to and from the phone. These waves are fairly inefficient, with phones effectively leaking power every time data is sent and received.

The Nikola Labs case collects this and feeds it back into the battery, slowing down how quickly it runs out of juice. Phones benefit most when downloading a large amount of data - such as when watching an HD Netflix stream - or even when placed next to a router, because radio waves passing by the phone also help to power the case.

Currently a working prototype, the Nikola Labs CEO Will Zell hopes the case will be a finished product ready to sell to consumers by early 2016, six months after his company's ongoing Kickstarter funding campaign ends. The campaign has so far raised $60,000 of its $135,000 target.

Zell said: "[The case] allows you to download power from the air and extends the battery life of your phone - there is no need for an external battery pack or some bulky battery case."

He adds: "We significantly extend your battery life between charges by simply using energy wasted from your phone...we were actually surprised about the amount of energy these phones waste. [Your phone] is constantly transmitting energy in the form of radio frequency waves [but] the vast majority of this energy is lost into the environment."

The technology could be used in other products, as well as smartphones. Zell told IBTimes UK that his company is looking at using the technology to extend the battery life of tablets, as well as wearable gadgets and even sensors fitted to buildings and inside offices.

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