Portable USB charger runs on AA batteries

This portable USB charger offers a point of difference: it's a DIY assemble-yourself kit that runs on AA batteries.

There's no denying that a portable USB charger is a handy thing to keep around. It can save a dying phone or laptop, at least long enough to make a few calls or save your work. But if you're the sort of person who forgets to charge a phone, who's to say you'll remember to charge up the charger, too?

The USB-U Portable USB Charger seeking funding on Kickstarter definitely has some possibilities in that regard. Like Adafruit's MintyBoost charger, it runs off AA batteries — but with a few key differences.

Unlike the MintyBoost, it runs off three AA batteries rather than two, allowing for a full amp of current as opposed to 500mAh; and, if you're not really the DIY type, or don't have access to a soldering iron, you can get it fully assembled. An LED light next to the USB port even allows you to use it as a small flashlight for when you're trying to charge your phone in the dark.

The battery power means that if you're anywhere around shops, you're guaranteed to be able to use it, and the whole kit and kaboodle fits neatly inside an Altoids tin.

"The USB-U Charger takes the power from three AA batteries (though it can run for a shorter amount of time on two) and converts it to 5V — USB Spec — by using a DC/DC Step-Up converter, the LT1308," explains creator Joshua Broekhuijsen. "This is essentially accomplished by creating a small magnetic field, and harvesting the energy from it as is collapses, storing excess in a buffer capacitor while the magnetic field is re-established."

Kickstarter funds will go towards improving the prototype: realigning the USB port, and potentially changing the diode selection to improve stability and longevity. The prototype itself has been tested on several types of smartphones, but Broekhuijsen would like to improve the range so that it works with as many devices as possible.

You may note that shipping is set at "US Only" on the Kickstarter page, but that doesn't mean you can't get one.

"As of right now, shipping will be offered to the continental US and (if messaged) Canada," Broekhuijsen said. "Those who have backed before this announcement will have their shipping costs covered (regardless of where), but to any future backers — if you are outside the continental US or Canada, please contact me and we'll see if we can reach an arrangement."

The USB-U Charger is being offered as a reward without tin for a minimum pledge of US$30, and with tin for US$32. You can find more information, and message Broekhuijsen about getting it shipped to Australia, on the Kickstarter project page.