My answer to With a 10400 mAh Xiaomi PowerBank, how many times will I charge my samsung A5?
Answer by Allen He:
2300 mAh battery
How many times can a 10400mAh power bank fully charge your samsung A5? Actually, this is a difficult question to answer.
The number of times a 104000mAhcan fully charge your device is relevant top 3 primary factors.
1.— What device you are charging with a 10400mAh power bank —
Generally speaking, a good rule of thumb is to divide the mAh of 10400mAh power bank by the mAh of your device battery.
So a 10400 mAh power bank can “theoretically” charge an samsung A5 from 1-100% 2.7 times (10400 / 2300 = 4.5). –iPhone battery capacity is 1810mAh
Keep in mind: this is never 100% accurate as there still some other factors involved which will influence the charging times, which is always higher than what a 5000mAh power bank can practically give. Keep reading…
2.— What is the device doing while it is being charged —
It’s not strange to see the device charged, for example, by a 10400mAh power bank, while you’re still using the device. So is there any difference between using the device while it’s plugged into and leaving the device alone or on airplane mode while it’s charged? The answer is undoubtedly YES.
If you are watching a movie on your device while the 10400mAh power bank is charging it, more power drained from the 10400mAh power bank and meantime it seems that your device is never charged. That is because you’re taking the power more quickly than the 10400mAh charges your device.
If you leave your device alone or on airplane mode while charging, you will get more fully charges since the device is not taking much battery charge at all while the 10400 mAh power bank is charging up the device.
3.— The charging cycles of the power bank 10400mAh —
More charging cycles the power bank gives, its capacity will reduce. Theoretically, the capacity will reduce to 80% after 300 charging cycles. If so, a 10400mAh power bank may have a 8320 mAh capacity. This is also relevant to the temperature when you’re using your power bank. And this point I believe you could find out on the manual when you brought the power bank.
4.— Both the calculation we mentioned above i think are right.
The power of 38.48KWh keeps unchanged when power bank output raise to 5V.
so 7696mAh/1810mAh = 4.2 times
The second one we usually we need multiply a transfer rate of the power bank capacity. usually 10400mah power bank will get only 10400mah * 0.8%=8320mah or so capacity in real.
8320mAh/2300mAh = 3.6 times
5000mAh rated power bank charge an iPhone 6 2 times
5.—Other Tips: As you can see, this is a very difficult question to answer. But I hopefully the information given here will be helpful. And welcome all to comment below or share to Facebook and twitter for more charging tips about samsung A5.