The prototype uses a rechargeable battery and patented technology which creates electricity by combining hydrogen and oxygen.
Intelligent Energy managed to incorporate the fuel system into the current iPhone 6 without needing to alter the size or shape of the device. The only cosmetic differences are rear vents that allow an imperceptible amount of water vapor to escape.
On the prototype iPhone, hydrogen gas is refueled via a modified headphone socket. Intelligent Energy is developing a disposable cartridge that would slot into the bottom of future smartphones and provide enough hydrogen-release powder for a week of smartphone use without recharging.
Interestingly, the company is said to be working closely with Apple. CEO Henri Winand refused to comment on rumors of Apple's involvement but told The Telegraph, "To our knowledge this has never been done before. We have now managed to make a fuel cell so thin we can fit it to the existing chassis without alterations and retaining the rechargeable battery. This is a major step because if you are moving to a new technology you have to give people a path they are comfortable with."
Mark Lawson-Statham, the company's CFO said, "Our view is that this is a couple of years out but really it’s about how quickly does our partner want to press the button and get on with it?"
We'll let you know if we hear any more details on whether Apple has partnered with the company. Please follow iClarified on Twitter, Facebook, Google+, or RSS for updates.