I bought a 10,000 mAh power bank about two months ago, which has a fast charging 2.0 port and a regular 1.0 USB-A port. I'm using it to charge my iPhone XS Max that supposedly has a battery capacity of 3,174 mAh. I expected to get around three full charges out of the power bank, but I'm only getting about one and a half before it runs out of juice. Could this be due to my using the fast charging port, or does the choice of port affect the actual usable battery of the power bank? Is my power bank possibly faulty?
4 Answers
Here's a thought: The 10,000 mAh capacity typically refers to a lower voltage. If you're using fast charging that boosts the voltage, your effective capacity can drop significantly – down to about 5,150 mAh when charging at 9V. This could explain why you're not getting as many charges as expected.
You also want to check the efficiency of your power bank. The 10,000 mAh rating is based on a specific voltage, and if you're using fast charging at higher voltages, the actual power delivered can be a lot less. Charging while using your phone at the same time can drain even more power, so that could be affecting how much your phone charges.
I’m not using my phone while charging, though. Last week it only charged from 16% to 40% even with three out of four lights on the power bank!
First off, was the power bank inexpensive? Sometimes cheaper models don't deliver on their promises, and you might be getting less than the advertised capacity. Even major brands can undersell some of their products, so it’s good to stick with well-known names like Anker.
Yeah, I paid about 30 bucks for it, so maybe that’s a red flag.
Heating can also cause efficiency losses, so keep that in mind. Losses happen when the battery transfers power to another device, especially with fast or wireless charging. For best results, you might want to try using the regular USB port instead of fast charging to see if there's a difference.
I was hoping to at least charge my phone twice with the power bank. It feels ridiculous that I can barely get one and a half.
If power banks can confuse us about their capacity, they should really use a more straightforward measurement like joules!