By Jonathan Davies

A UK tech company has developed a prototype battery for the iPhone 6 that last a week.

One of the constant bugbears of Apple's customers is the battery life of the iPhone. But Intelligent Energy has developed a fuel cell that generates power by combining hydrogen and oxygen.

The British tech firm fitted the battery to the iPhone 6 and found it didn't need to be recharged for a week, without the loss of performance.

“We have managed to make a fuel cell so thin we can fit it to the existing chassis without alterations and retaining the original battery," Intelligent Energy’s CEO Henri Winand told The Telegraph.

Winand explained that once the battery does need recharging, hydrogen gas is pumped through a modified headphone jack, rather than a plug in the wall.

The fuel cell is still just a prototype, but Intelligent Energy is looking to commercialise the product. Mr Winand said: “It’s about how quickly does our partner want to press the button and get on with it?”