I bought this Signalex 1200mAh power bank from Poundland. It really did cost just £1. It’s a bit rubbish, but it’s ok for the money if you only need to charge up something small. It’s not really suitable for a decent smartphone though and you can get a much better power bank for not much more money.
In the box
The box contains the power bank, a small USB to Micro USB cable and a keyring loop. The power supply was empty when I opened the box.
- Dimensions: 96 x 22 x 25 mm
- Weight: 58 g
- Micro USB cable length: 28 cm
- Input: 1 micro-USB
- Output: 1 USB A - 5V up to 1A
Claims to deliver 1A, seems to suffer significant voltage drop at 1.3A before turning off. Perfectly fine.
The cable is 28cm long. It has some strain relief but it’s not very flexible. At 2.1A it drops 1.2V - 20% which is just awful for a short cable. Even at 1A it will drop 10%. Throw it away, it will waste what precious little power this power bank contains.
Delivered 1A with the voltage dropping from 4.95V down to just under 4.5V over the course of the test. It delivered 617 mAh at 5-ish volts, or 2942 mWh, which is ~66% of the rated capacity (1200mAh * 3.7V). Not very efficient.
It did not cut the power off cleanly at the end - with the supply pulsing on and off with increasing frequency at the end.
None really. There is a charging indicator which stops flashing when it is full. It seemed to work.
Standby Power Loss
It arrived empty. I did a teardown on this one, so I can tell you that the standby current seems to be ~115µA, so it will run the battery down in around a year.