Let the sun charge your stuff: Get a 20,000-mAh solar power bank for 50% off

Solar-powered portable chargers are sort of like my grandfather -- neither can be rushed. The energy density of solar cells is just too low to charge a battery quickly, so it can take several days to do what a wall outlet can do in hours. But RAVPower's 20,000-mAh power bank can be charged via a wall outlet or solar energy, which makes it quite versatile. It usually sells for $50, but right now it's 50% off. You can get the RAVPower 20000mAh Solar Power Bank for $25 when you use discount code UHV9BY6O at checkout. 

Keep in mind that you're not going to live off the electrical grid with a solar charger. It can take about a week to fully top off one of these power banks, which is why most of the time you'll just plug it into the wall. But you can leave it near a window for free, all-day charging and, if you take it on a camping trip, it can keep your phone topped off when a similar 20,000-mAh battery would have breathed its last breath. 

Speaking of which, the power bank has a pair of USB ports to charge two devices at once and the whole doodad (in technical terms) is rugged enough for the great outdoors: it's IPX4 splashproof, dustproof and able to withstand shocks and drops. It also has a powerful LED panel that provides a generous amount of illumination for wandering around in the woods at night. 

This article was previously published. It has been updated with new deals and pricing. 

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