GoalZero offers unlimited, portable backup power for complete peace of mind. I use mine for outdoor neighborhood movie nights!
Goal Zero Yeti 1400 Lithium Portable Power Station
Offering easy-to-move power for basecamp, road trips and festival campgrounds, the Goal Zero Yeti Lithium 1400 portable power station keeps all kinds of devices charged up when you're on the go. Available at REI, 100% Satisfaction Guaranteed.