Meet the Lifepack Stealth Backpack: a backpack with a solar panel, power bank, and Bluetooth speakers. It can charge your smartphone up to 6 times. It generates 1 extra charge after 4 hours of sun exposure. The battery lasts up to 96 hours. 
Also see:
The bag is water resistant. It comes with a retractable lock to lock all compartments of the bag together.
*Disclaimer*Our articles may contain affiliate links. As an Amazon Associate we earn from qualifying purchases. Please read our disclaimer on how we fund this site.