How Long Will A 20,000 mAh Power Bank Typically Last?

If you need to charge your phone repeatedly while away from an outlet, a big power bank could be a good investment.

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20,000 mAh power banks tend to be chunky and are considered unwieldy for most pockets — but despite their size, there are plenty of situations in which you might rely on one. Large power banks are perfect for camping trips or site visits where your phone may not have access to an outlet for an…