Youmile 1 pcs 5V 2.4A 186 50 Charging Board Mobile Power Bank Module Dual USB 186 50 Lithium Battery Charger Board Digital LCD Display Protection Module with Fast charge data cable

Good product, doing what should.

I've salvaged couple of 4200mAh Li-ion batteries from a notebook, changed the BMS to 1S on each, added a common connector to mate to the charging PCB and for less than £8.00 have a battery bank with two batteries. I just the battery management and 5V outputs. Great phone charger.(5/11/22 Update) multiple li-ion battery type charged and tested, the % reading indicates accurately between packs. The differing inputs makes charging more versatile, I've made the first unit into a simple 3.7V lithium battery tester and ordered two more units.

I bought this to power a micro controller but that does not draw enough current to keep the 5V output on so it switches off after a few seconds. Otherwise it really good at what is does just not for my intended application. The choice of sockets is really handy.

I recycle old laptop batteries on a regular basis and have found this board a good addition to making up small scale battery packs, it supports multiple inputs and outputs, it charges reasonably quick, and the board and battery pack do not get warm, the LED indicator is useful tool, in the time i have had these and made some packs up have found there was no power loss by just sitting, i have made up some packs with just heat shrink for the batteries and as industrial as they look they are reliable, for a project you might want to find a suitable case to fit these in. how ever even to sit this in a project is still i nice touch.with this build the batteries are all parallel so no need for a battery balance board.