It seems like there are just never enough electrons in your phone, right? With just a few thousand milliampere-hour, it can be easy to drain your device before there's an outlet handy, so it's a good thing portable battery packs exist. If you're carrying something extra anyway, you might as well go big. A Crave Travel Pro 13,000mAh battery that should work nicely is on sale over at Amazon.

2014-07-11 04_52_47-Place Your Order - Amazon.com Checkout

The 13,000mAh battery on offer here has solid reviews on Amazon and usually sells for $40. Using promo code TB2UHVG6 at checkout, you get it for just $28.99. The Crave Travel Pro has two USB ports for charging your devices and a digital readout on the front that tells you how much juice is left.

This seems like a reasonable deal – there are a number of batteries in the same capacity range on Amazon that cost quite a bit more. The Crave Travel Pro is eligible for Amazon Prime, so you can get it shipped fast and cheap if you've already given Amazon your money.

[Amazon via Fatwallet]