Few weeks ago I bought Xiaomi 10400mAh portable power bank and wanted to test it, how it would work replacing my wall charger and become my only charger on daily bases. I'm quite impressed with results. I was able to run my iPhone 5S for 10 days without using any other power source other than my Xiaomi power bank.

Note: I work in IT and spend my days near computer, so I have very little use for my phone. Usually it just stays in my pocket whole day and is used only for calls, texts, and often for Waze navigation.

Here is data from charging and phone usage from my experiment:

I started this test on 21st of January at 00.00.

21.01

20.00 started charging at 35%

Usage: 2.5h Waze, 2 calls, 10 texts, 1h Chrome

20.00 started charging at 35% Usage: 2.5h Waze, 2 calls, 10 texts, 1h Chrome 22.01 21.00 started charging at 30%

Usage: 2.5h Waze, 1h web, 3 calls, 2 texts

Usage: 2.5h Waze, 1h web, 3 calls, 2 texts 24.01

16.00 started charging at 40%

Usage: 1h web + 1calls

16.00 started charging at 40% Usage: 1h web + 1calls 25.01

22.00 started charging at 40%

Usage: 2h web 3 calls

22.00 started charging at 40% Usage: 2h web 3 calls 26.01

20.00 started charging at 20%

Usage: 2h web, 3h Waze, 3 calls

20.00 started charging at 20% Usage: 2h web, 3h Waze, 3 calls 28.01

19.00 started at 3%

Usage: 3h web, 20min calls, 20 texts

19.00 started at 3% Usage: 3h web, 20min calls, 20 texts 29.01

20.00 started charging at 30%

Usage: 1h web, 2.5h Waze, 3 texts, 3 calls

(Power bank was empty after this recharge, was able to recharge phone till 98%)

20.00 started charging at 30% Usage: 1h web, 2.5h Waze, 3 texts, 3 calls (Power bank was empty after this recharge, was able to recharge phone till 98%) 30.01

Phone battery died at ~22.00

In my opinion these results are excellent for 20$ power bank. Additional bonus is the looks, nice brushed aluminum looks very great and no way anyone could tell this power bank is so cheap.