An iPhone 6 that stays charged for a week? New tech may be on the way 

The Holy Grail of mobile devices – long charge times – may be within reach, thanks to a British energy company that has developed an iPhone that stays charged for a week.

Remember when cell phones lasted for days on one charge?  Smartphones like the iPhone ended all of that.  The iPhone 6 is as powerful as a laptop once was and battery life has suffered as a consequence.

Intelligent Energy thinks it has an answer, according to a report in The Telegraph. The U.K.-based firm has come up with a working iPhone 6 prototype powered by both a conventional battery and a hydrogen fuel cell – the latter creates energy when hydrogen is combined with oxygen.

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And the company has done this without altering the size or shape of the device, an Intelligent Energy spokeswoman confirmed to The only difference are vents to emit water vapor – the one byproduct of a fuel cell.  “Refueling” of the cell is done via an “adapted” headphone jack.

A commercial version of the fuel cell would slot into the iPhone with a cartridge that could power the phone for a week without recharging.

Maybe just as intriguing: the report claims the company is working with Apple.   The company spokeswoman would not comment to on any kind of collaboration with Apple outside of selling its Upp reusable fuel cartridge -- which can provide up to 5 full smartphone charges -- at Apple stores in the U.K.

Problem is, battery life is not improving 

Intelligent Energy is trying to solve a longstanding annoyance for modern mobile devices: frequent recharging.  The newest and largest iPhone, the 6 Plus, for example, can last for a day or two – depending on what you’re doing – but that’s still frequent enough that you always have to plan for recharging.

“Take into account the more power hungry hardware, more powerful chips and larger, better resolution screens, overlay that with exponentially more sophisticated software and you are holding in your hand the insatiable little monster that is a modern mobile phone,” according to a recent blog post on Intelligent Energy’s site.

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The blog quotes former Motorola President Rick Osterloh, who told the BBC that he is waiting for an “unforeseen leap” in battery technology. That’s an often-heard refrain from executives at mobile device makers because battery technology hasn’t improved enough to keep up with the energy-hungry technology and features being packed into the latest phones, tablets, and laptops.

And fuel cell technology is already competing with batteries in cars.  Toyota recently announced that it is taking orders for its Mirai fuel-cell vehicle, which will compete with Tesla’s battery-powered electric cars.

Echoing the concerns of Osterloh, Toyota doesn’t believe batteries are the long-term solution for alternative fuel cars because battery technology doesn't offer the breakthroughs necessary to power future cars for long distances.

But consumer devices are another story.  And it's ultimately up to a large device maker like Apple to determine if fuel cells are viable in a phone and then adopt the technology in-house.

Apple did not respond to a request for comment.