Most of us think of power banks as small, smartphone-sized battery packs that can be slipped into a pocket or clamped onto the back of a smartphone. But there's a category of power banks that are much bigger and beefier than that -- and they certainly won't fit into a pocket.
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Take theBluetti X20 , a power bank built to power laptops and other high-capacity devices. Sure, you can use it to charge your smartphone or earbuds, but that would be overkill.
The X20 is big. It's a massive 153.6Wh / 12Ah unit measuring 8.1 inches