Warning ! Apparently there is another variant of this power bank with PCB using FM6316CE ic that appears to be very problematic, perhaps even dangerous. Seems like white color power bank is still OK…
This generic power bank appeared rather recently in many shops with very decent specifications and incredible price in 2-3 $ range ! Although I have no means to test it thoroughly as some other members, some basic info might be helpful…
Construction of this power bank is rather simple and straightforward to use with clearly marked input and output ports.
Only unprotected cells are supported…
Closing lid is quite sturdy and keeps everything nice and tight inside but it might be a little difficult to open.
Overall build and plastic quality is superb and surprising for this price range, even usb connectors feels solid.
Positive battery tab and negative side spring are also high quality and will ensure reliable connection to battery.
Circuitry is based on a brand new ETA9635 ic that combines li-ion charger, protection and step up converter in a single 8-pin SOIC package !
Specifications promise up to 1A/5V output with high efficiency of 85% for 0.9A output and 92% for 0.5A. Battery charging (cc/cv) current is also specified up to 1A. It also promises short circuit, overload protection and 2.8V cut out voltage along with 50uA quiescent current.
PCB looks quite decent.
View of indicator led’s and battery positive tag.
USB output is AFAICT apple coded and it provides 0.5A current to android devices.
Output voltage is well in range of usb specification and quite stable (near 5V or slightly under)
Output current is just a little bit below 0.9A and fairly stable and no detectable heat is produced.
Actual charging current is 0.9A and it seems that cc/cv pattern is followed properly. When battery is full charger stops charging completely. Termination voltage is in 4.17-4.19 V range on all of four power banks I tested and termination current is around 100mA.
Two indicator led’s indicate status of charging or discharging in following pattern:
RED is lit while charging battery, BLUE and RED when done.
BLUE and RED is lit while discharging and battery is over 4V, under 4V only blue remains and shuts off when battery is depleted.
Led’s are adequately bright while charging but when discharging they are barely visible, especially as white lid blocks quite a bit of light…
Overall this is a great little power bank. Quality is mind blowing for it’s price and all examples I tested worked flawlessly and ensured safe operation for both battery and device charged. Weak led indicators are IMHO only real drawback…
It’s available in several colors at popular web stores (currently 1.99$ at BIC)