Smartphone battery life isn't getting much better any time soon.
Even the market-leading Xperia Z3 can only just eke out about two days of juice. And whether that's because we just can't stop using our boxes of lights and whizzbangs, or because the tech for a genuine step up (graphene?) just doesn't exist yet, the result is we're going to have to find another solution in the interim.
In theory - and to be fair, in practice across most of Asia - the answer is personal battery packs. These devices are essentially extra smartphone batteries in a box, and come in a variety of sizes and costs. They're pretty fool proof, but they have two downsides: the capacity is limited, and they still require a plug to charge just like a smartphone.
Is there another way?
There is. It's expensive, it's big, it's impractical, and it's as futuristic as anything on the consumer tech market. It's an 'Intelligent Energy' Upp Proton Exchange Membrane fuel cell, aka an at-home power station.
The Upp is a two-part gadget (£149) which compromises a fuel cell, with vents on the side and a USB port, and a fuel cell cartridge which contains 2.23g of hydrogen gas stored in hydralloy C5. From these two parts energy - beautiful, charging energy - is created.
It sounds terrifying, and it sort of looks like it too. Together the device stands about 18cm tall in black and grey, and weighs a combined 620g. When it's charging (just plug in any USB-charging device and turn it on) it heats up slightly around the vent, and occasionally clicks. It's not dangerous - you can even fly on commercial jets with it (though we suggest taking documentation with you and be prepared for a wait at security). But it feels instinctively cutting-edge, with all the suspicious glances that implies.
To use though, it's very satisfying. The two parts click together with an exceptionally welcoming snap (we found ourselves idly snapping and unsnapping them at will, which is not a great idea obviously) and there's an included iOS/Android app which can tell you how much juice is left, other usage stats and (eventually) where to go to get a refill.
That's right - refill. Because the point of a fuel cell is that it's producing power from a consumable store of hydrogen gas, and so once it's empty you have to recharge the cartridge (£10 a time) or plug in a spare (£45). That's pricey. It's also inconvenient. At the moment there appear to be no UPP Partners in central London to get a refill, at least according to the app, so you have to rely on the website. Eventually they'll come, but we have no idea when.
Fortunately you get a decent amount of fuel for your cell. Each one is rated at 25Wh which should charge a smartphone several times, though not perhaps an iPad Air. It charges quick too - about as fast as the mains.
It's also helpful that the aforementioned app is so straightforward, and capable of letting you know in advance when you're likely to need a refill and what the status is. There's a battery protection mode built in too, which shuts off charging when you hit 85%, as well as a Fast Charge mode.
The problems are obvious - convenience and price. It's not expensive compared to the competition - the 5Wh myFC PowerTrekk is £160 - but it's still a lot of money to pay unless you're planning something specific.
We used it on a busy day around London, and it didn't really make sense compared to a battery pack. It was fun knowing we could stop anywhere and literally generate power from gas, like a god or something. But really we weren't so desperate that we couldn't have found a power outlet if we'd really needed to, or used a spare battery with a bit of planning.
But the potential is also obvious. Imagine knowing you'll be travelling somewhere remote without access to power for significant stretches, or needing an emergency backup in the event of setbacks (or zombie apocalypse)? If you're going off-grid, or enduring an especially trying day somewhere bizarrely inexplicable, the UPP is perfect for that.
As a gadget, it's simple, attractive and fool-proof. It's not ridiculously heavy or large, it's versatile and works as advertised, whenever you need it.
We're not all going to be carrying hydrogen fuel cells any time soon, but when the zombies arrive we might learn to love the UPP very quickly indeed. For now it's still a specialist tool - maybe a bit 'beta'. But it's pretty awesome and hard not to love, if you need one.