Running out of battery on your smartphone is almost inevitable these days, which is why there are so many mobile charger options. But all of them take up room making carrying them awkward, until now with the TravelCard.

Start-up company, Go Design has smashed its Kickstarter goal and will be selling its TravelCard chargers that are the size of a credit card. That means you'll be able to slip the device into your wallet or pocket for extra charge without even noticing it's there. And it's lightweight aircraft grade aluminium body should be able to handle anything you throw at it.

The card sized charger, at 4.7mm thin, has either a micro-USB or Lightning connector built in so cables aren't needed either. Plug the phone in, hit the power button and let it juice up your mobile. You can glance at its LED lights to show how much charge it has left. The TravelCard recharges to full in 75 minutes.

Go Design says the charger will be able to offer users an extra 5 hours talktime, 4 and a half hours of internet use and 98 hours of standby time. Presumably this is referring to the iPhone since Android phone battery performance and size varies hugely. But with 1,300mAh in the charger you can expect enough power to keep you going all day without any worries.

The TravelCard is still available on Kickstarter for $35, which is about £21. The retail price will be $45 which is about £28. It comes in White, Black, Silver and Sapphire Blue.

READ: Which mobile battery charger is best for you?