“Using a short (300mm) USB cable this Powerbank Bank will power a Raspberry Pi 3B+. it can be assumed that earlier RPi versions will be easily powered. A longer cable such as the 800 mm cable attempted results in too much power loss with much switching ON and OFF of the RPi.
It follows that this Power Bank will easily recharge a smart phone and some.”
“I can't fault this as a power bank, but note that it has a few behaviours which make it a bit awkward for use as a constant power source (which is what I'm hoping to use it for). Without a sufficient load, this will output at ~2.3V until it detects enough current flowing (seems to be somewhere around 30mA) then it will increase to 5V (with ~0.5s delay). For smaller loads, I found that adding a 470µF smoothing capacitor was able to draw enough inrush current to be detected. It will also occasionally drop back down to 2.3V for a moment, presumably when the current is too low for too long. This means most uses which need a constant voltage will need a voltage regulator (fortunately devices like the Pi Pico include one already, but for peripherals wanting to use the full 5V from VBUS/VSYS you'll need your own regulator).
It would be nice if there were more tech-specs available for this, but it's aimed more at end-users wanting to charge another battery, so doesn't include any details about its electrical behaviour.”
