AmazonBasics Portable Power Bank with Micro USB Cable – 3,000 mAh – Link 
Hurry on over to Amazon where this is currently marked down to only $5.09!
- Portable battery pack with 3,000 mAh capacity. Powered using a lithium-ion polymer battery for reduced weight and increased safety
- Plugs into Micro USB 2.0 and 3.0 ports to charge your smartphone (like a Samsung Galaxy S6 or Note5) or Bluetooth headset. Micro USB cable neatly stows when not in use
- The 3,000 mAh battery power will charge a Samsung Galaxy S6 one complete charge and then again to nearly 20% before the power bank needs to be recharged
- Power overload protection; USB charging cable and carrying pouch included
- Measures 4 x 2.5 x 0.3 inches; weighs 2.3 ounces
- Backed by an AmazonBasics 1-Year Limited Warranty