Here is a smartphone power bank that you can charge with sunlight or a hand crank mechanism. The AYTECH Hand Crank Solar Phone Charger has a 10,000mAh battery and dual USB charging ports. It also has a torchlight to get you out of trouble in the dark.
This power bank is waterproof and shockproof. It can be charged in about 5 hours using its hand crank. You can find out more about it here.