Good thing is that it works - and by that I mean - it charges the battery. Unfortunately there is 1 design problem I found and also one assembly problem. Design problem is that it overcharges the battery - my 18650 battery got to 4.34V and after a while it stopped charging and voltage started to drop, but the voltage should never exceed 4.2 V!!! The assembly error of all my 3 pieces is: the battery socket is mounted in reverse!!! (see the picture) There are 3 markings of +/- battery sides on the module. One outside the battery socket, on the board. One inside the socket, also on the board. And last one on the black battery socket itself - and this one shows opposite +/- directions from the previous ones. The last one is the incorrect one. This error greatly increases the chance of connecting the battery wrong way and frying the board.

Good thing is that it works - and by that I mean - it charges the battery. Unfortunately there is 1 design problem I found and also one assembly problem. Design problem is that it overcharges the battery - my 18650 battery got to 4.34V and after a while it stopped charging and voltage started to drop, but the voltage should never exceed 4.2 V!!! The assembly error of all my 3 pieces is: the battery socket is mounted in reverse!!! (see the picture) There are 3 markings of +/- battery sides on the module. One outside the battery socket, on the board. One inside the socket, also on the board. And last one on the black battery socket itself - and this one shows opposite +/- directions from the previous ones. The last one is the incorrect one. This error greatly increases the chance of connecting the battery wrong way and frying the board.

Good thing is that it works - and by that I mean - it charges the battery. Unfortunately there is 1 design problem I found and also one assembly problem. Design problem is that it overcharges the battery - my 18650 battery got to 4.34V and after a while it stopped charging and voltage started to drop, but the voltage should never exceed 4.2 V!!! The assembly error of all my 3 pieces is: the battery socket is mounted in reverse!!! (see the picture) There are 3 markings of +/- battery sides on the module. One outside the battery socket, on the board. One inside the socket, also on the board. And last one on the black battery socket itself - and this one shows opposite +/- directions from the previous ones. The last one is the incorrect one. This error greatly increases the chance of connecting the battery wrong way and frying the board.

Well packaged, received in good condition and excellent delivery time (12 calendar days from order). I run many of my home automation projects on 18650s with micro-controllers waking from deep sleep, polling sensors, and sending the data wirelessly to a central point. These modules do a good job of looking after the batteries and I am happy to recommend them.

Well packaged, received in good condition and excellent delivery time (12 calendar days from order). I run many of my home automation projects on 18650s with micro-controllers waking from deep sleep, polling sensors, and sending the data wirelessly to a central point. These modules do a good job of looking after the batteries and I am happy to recommend them.

Well packaged, received in good condition and excellent delivery time (12 calendar days from order). I run many of my home automation projects on 18650s with micro-controllers waking from deep sleep, polling sensors, and sending the data wirelessly to a central point. These modules do a good job of looking after the batteries and I am happy to recommend them.