The Nipper smartphone charger claims to be the smallest portable smartphone charger and what’s better is it’s powered by two AA batteries!

The tiny device can fit on your key ring and although it won’t fully charge your phone, it’s designed for emergency use when you just need a little boost to last until you’re back in the vicinity of a wall charger, for example.

The Nipper cube measures 17x17mmx17mm and weighs only 10g and can fit in a bag or pocket (although be careful if you store it in your back pocket and then sit down – a plastic cube sticking in your bum cheek can be nasty!).

Then, when you need to charge your phone, just open the cube up, pop in two normal batteries and start charging away!

The Nipper only works with devices that use a microUSB adaptor, so isn’t yet compatible with the iPhone, although the company is currently developing a version that will work with iDevices.

The device will add an extra 10 minutes to your phone’s battery in 30 minutes and 20 per cent in just over an hour, but the power output will vary according to how big your phone’s battery is and how powerful the device. It will also change according to the AA batteries you use – cheaper batteries are unlikely to give as much power as Duracell, for example.

The way in which the Nipper will be bulk manufactured depends on the popularity of the campaign. If small volumes are required, they will be 3D printed. If larger volumes are needed, they will be injection moulded from polypropylene. The two halves of the cube are connected with fabric or leather straps.

The company decided to use AA batteries to power the device because: “AA batteries are the most universally recognised and widely sold type of battery. While it doesn’t make sense to rely on AA batteries for daily phone charging, they do come in handy if you’re in an everyday emergency and need that crucial bit of juice.”

You can buy a Nipper from Kickstarter for £15 or get the premium version (with leather straps and gold-plated contacts) for £20. The company was appealing for £6,000 funding and has already surpassed its goal with 22 days to go.