I bought this Aukey 20,000 mAh Dual USB and Lightning power bank from Amazon UK. I paid £21.49, but it normally seems to be available for between £20 and £23. It doesn’t have many fancy features, it’s brick shaped and heavy, but it is a solid powerbank with an impressive capacity for a good price. Recommended.
Buy this from Amazon UK - This link contains an amazon referral link which helps me to buy more power banks to test.
In the box
Inside the box is the powerbank, a micro-usb cable, and a nice mesh case to keep them in. There’s also a small manual and a 24 month warranty card.
There’s a lightning port for charging in addition to the normal micro-USB port, so if you’re an Apple user you don’t have to carry an extra cable to charge the powerbank.
- Dimensions: 147 x 82 x 21 mm
- Capacity: 20,000 mAh / 74 Wh
- Weight: 381 g
- Micro USB cable length: 30 cm
- Input: 1 micro-USB and 1 lightning
- Output: 2 USB A - 5V up to 2.4A, 3.4A maximum.
- Hold-on current: 75 mA
No autodetection of anything being plugged in, so you must press the button before the power is turned on. It advertises 2.4A on each port, which it delivers at a nice steady 5V. Noticeable voltage drop occurs above 2.6A which is well above the claimed specification. Both ports together deliver 3.4A as claimed.
Hold-on current is relatively high at around 75mA, and it cuts power after just a few seconds if there’s no noticeable drain.
Limited strain relief, but feels like quite a thick cable. There’s a USB logo on the correct side of the USB-A end. At 2.1A the cable drops 0.17V, or 3.4% which is good for an included cable.
During the discharge test the voltage was consistently close to 5V throughout, and the power bank had no problem supplying a steady 2.4A. It cut the power off cleanly at the end of the test. It delivered 60,294mWh of a maximum possible 74,000, which is 81.5% efficient, which is fairly standard.
The display consists of 4 LEDs showing whether the power bank is 25, 50, 75 and 100% full. They seem to be a reasonable representation of the available capacity.
Standby Power Loss
I bought this in June 2018 and had left the box unopened. The power indicator shows 50-75% remaining in October. I’m not sure how full it was when it arrived, but the standby loss appears to be perfectly acceptable.