How long does a power bank last in a day? Take a 10,000mAh power bank to demonstrate. Its rated input is 5V/2A, so if you use a 5V/1A power adapter to charge it, its actual input current is 1A=1,000mAh. 10,000mAh /1,000mAh=10 hours. AceBeam IMR21700NP-510A if you want powerbank option. I have one & it's great. Little slow to recharge, 75g. 1. JKBFree • 4 mo. ago. I use the clutch and its about as skinny as a few credit cards. -2. M23707 • 4 mo. ago. great suggestions - a good smaller power bank is a must. Z4OqUgG.

how long will 5000mah power bank last