amazon.com
has the CoolStar 36800mAh 18W Quick Charge 3.0 Solar Power Bank for $14.99 with free shipping on $25+ or with Prime.

• Has two 5V 3.1A 18W fast charging Outputs and has 2 supper bright LED lights, high-precision compass has been built in the Solar phone charger, In addition, it has a carabiner and a charging cable!