12/02/2014 02:49 pm ET Updated Dec 06, 2017

This Keychain Lets You Charge Your Phone With A 9-Volt Battery

Smartphone batteries are horrible -- we all know that. Sure, you can buy one of those backup battery packs to help you out, but if you’re like me, you forget to charge them ahead of time. Or you could be one of those people with your charger in tow, always hunting for an outlet.

Flintu, an Australian creative duo, says it has an easier fix: a keyring-sized device that charges your phone with a 9-volt battery. The team is calling the device Plan V.

flintu charger phone
Plan V is an adapter that charges your phone with a 9-volt battery.

Measuring just 4.5 centimeters by 1 centimeter and weighing 7 ounces, the device is meant to clip conveniently onto a keyring. The catch is that it doesn't have any juice itself, so you'll have to carry a 9-volt battery with you or stop into a convenience store when the time arises.

While this may seem like a hassle, you won’t have to charge an external battery pack or case every night, nor will you have to carry around a charger and ask the waitress to plug your phone in behind the bar.

flintu keyring key
It's hard to forget Plan V when it's with your keys.

Snap one of the batteries into place, plug the charging device into your phone and you'll supposedly get around four hours of additional talk time, according to the product's website. Here it is in action:

Electrical engineer Evan Stuart and creative designer Luke Trevitt, who make up the Flintu team, have taken to Kickstarter to raise the funds to mass-produce Plan V. On their Kickstarter page, the two compare the system to a car jumper cable, although that comparison is a bit odd since you can't rely on sucking juice from a friend's smartphone.

Plan V may not be the cheapest solution -- a 4-pack of 9-volt batteries typically costs more than $10, and each 9-volt is only good for a few hours of battery life. But it's surely an innovative solution to the ongoing struggle of keeping our phones charged.

The creators have already met their Kickstarter goal of AU$30,000 (about $25,000 U.S.) to start manufacturing, and by February 2015 they plan to ship the devices to people who backed the campaign. The product contains a micro USB port, so it'll work with nearly all smartphones except the iPhone. But according to the Kickstarter page, the duo also plans to create a Lightning port version for iPhone users, which it hopes to be selling by March 2015.