Intelligent Energy is the British company that could make your phone battery last a week on a single charge

There can be few bigger opportunities in tech right now than making phone batteries that last for days at a time. An iPhone that stays awake as long as a Nokia 3210 did? The queues outside Apple Stores would snake into the countryside.

British firm Intelligent Energy believes it’s sitting on such an opportunity. The company designs long-lasting fuel cells to fit inside devices, from the four-wheel drive sitting on your drive to the phone in your pocket. In August, the company demonstrated how its hydrogen-based cells could be fitted inside the chassis of an iPhone 6, the only cosmetic difference being the vents on the rear of the device that allow a minuscule amount of water vapour to escape (fear not, there’s no need to worry about damp pockets, as we’ll explain later).

Speaking of water, Intelligent Energy hopes to emulate the huge market for bottled water with its phone fuel cells. Nobody really needs bottled water, in the same way nobody really needs fuel cells. However, just as you can’t turn on a tap and slurp a glass of water on the way home from work, you can’t charge your phone while waiting at platform 9. The sheer convenience of popping a fuel cartridge into your phone, tablet or laptop makes mobile power a £300 billion-a-year opportunity, according to Intelligent Energy’s CEO Dr Henri Winand.

It’s all in the cells

Fuel cells have been in the pipeline for some time, but we’re now excruciatingly close to seeing them arrive in consumer electronics. They’ve already been widely deployed in other industries. A quarter of the world’s leading car manufacturers have signed licensing deals with Intelligent Energy, whose fuel cells already appear in models sold by Suzuki and in adapted London cabs.

The company recently signed a £1.2 billion deal to install fuel cells on mobile telecom towers in India, providing much-needed reliability for the country’s 935 million mobile phone users. “The whole ethos is the world is getting more and more distributed all the time, where people want to be able to do what they want, wherever they are at that moment,” Dr Winand told Alphr. “That means that the 20th-century model of centralised power that is being used at the edges is no longer applicable.”

The desire for portable power is perhaps felt most urgently among phone users, who have grown used to seeing their battery bars evaporate before they’ve even made it home. Intelligent Energy already has a product on sale that caters for this eventuality in the form of the Upp USB power pack, but it hardly screams convenience.

The charger and clip-on cartridge are roughly the size of a can of Red Bull and weigh almost four times as much as an iPhone 6s. The device itself costs around £150 and each cartridge costs another £35, with refills at £6 a pop. These charge the average smartphone around five times.

Winand admits the Upp is far from the perfect solution, but says it has served its purpose. “Upp, for us, is a way to make sure we understand the consumer,” he said. “Each time someone uses an Upp, we aggregate all the data… and understand what people are willing to pay for, we understand broadly what they charge and when they charge it. The UK data has already shown that the biggest peak for charging is between 6am and 9am.” Presumably that’s because they’ve forgotten to charge their phone overnight and need some power to check Twitter on their morning commute to work.

The Upp looks like the brick phones of the late 1980s compared to the prototype fuel cells that Intelligent Energy showed off in the summer. Designed for laptops and phones, these don’t even need you to open up the chassis to insert a new cartridge – Apple clearly wouldn’t countenance such an inelegant design. Hydrogen gas is refuelled via an adapted headphone socket, with enough hydrogen in each cartridge to keep a phone topped up for a week.

One alarming side effect of the technology is that the fuel cells discharge a small amount of water vapour, and the idea of droplets of water running around inside your £600 smartphone is not a particularly reassuring one. Dr Winand claims you and your phone simply “won’t notice it”, and that “it’s not something that’s going to give you a drop of water in your pocket”. He added: “It’s far less than what we do in sweat every day,” hopefully not with Tony Blair giving a conference speech in mind.

The biggest challenge the technology faces is getting the price right: how much will people pay to top up their phone on the go when they can do so at home for next to nothing? Winand said critics made similar arguments about bottled water. “If I could charge you the price of a well-known brand’s cup of coffee for a week’s worth of energy, that would be a £300 billion-a-year market,” he said. “Many people thought in the seventies that bottled water would never work, apart from disasters and emergencies and military use… and we all buy a bottle of water every day when you can get it from the tap.”