This pair of 22.5W power bank (bidirectional) fast charging module comes with no instructions on how to use it. Which makes using it frustrating. The markings on the IC used by the module are abraded off, so that the chip type can not be determined by inspection. The module has five LEDs and a push button switch. Using the internet, yielded this information about the function of the switch that is located on this module. “A short press on the switch opens the USB port for external discharge. A double click action closes the USB port (i.e., turns module off). If there is an external power supply present, only the output port will be closed.” Four of the LED’s seem to indicate battery charge. The module comes with an NTC sensor for use in preventing over-temperature. When I attached an 18650 cell to the battery leads of the module, it seemed to only charge it up to 4.07V, which is lower than I would have expected (4.2V is full charge voltage). When current was pulled from the USB port, which had a no-load voltage of 5.1V, the unit shutdown with a current pull of about 0.5A, which again seems low. The module might require multiple cells in parallel to allow reasonable current draw. With no instructions, the issue might be that I am using it wrong. However, as it is, I am not impressed. I would pass on this module. Read more

It allows for charge and discharge on the same USB-C port Don't have to worry about pushing the button you plug it in and it does everything automatically. Make sure you have at least 4000ma to avoid voltage drop in Read more