Nitecore NB20000 GEN3

The Nitecore NB20000 GEN3 packs 20,000mAh into a 291g carbon-fibre shell, making it one of the lighter power banks in its capacity class. USB-C output up to 22.5W allows fast charging of a phone and other devices, while IPX5 protection handles rain and splashing water on the trail. At 20,000mAh, it's good for roughly four to five full smartphone charges, making it a realistic option for multi-day treks with no access to power — whether that's thru-hiking or longer expeditions where a phone doubles as GPS and camera and needs frequent top-ups. The trade-off for higher capacity is more weight than the smaller models in Nitecore's NB line, so the NB20000 GEN3 makes more sense for extended trips with limited charging opportunities than for short weekend outings, where a smaller, lighter bank would suffice.