12pcs 1S 3.7V 4A 18650 Charger PCB BMS Protection Board for Li-ion Lithium Battery Cell

It worked as expected.-

Keep in mind these are to protect from over or under charging, but do not have overcurrent protection. I burned a couple out this way, that was my fault.

I'm using these on single 18650 cell lower powered solar project and they're been working great. I do notice it seems to cut them off more at 4.1v but that's perfectly fine with me. As others have noted there is no discharge protection as you have to pull your power right off the same pads as the battery. My panels are a bit oversized for the power I draw anyway so this hasn't been a problem most of the time. One unit has an esp32 though and it pulled it down to 1v in no time. Lesson learned but these definitely still have a place as cheap charging protection.

Bring safety to the next level!

So far OK, B+ B- and P+ and P-what looks like an R- is probably a B- as well?

Over and under voltage protection work as advertised. Works continuously at 3A no issues. Good value product.

Does what it claims controls charging into the cell and it allows higher charge amperage than most modules. It was my fault for not paying attention to the fact that is has no solder pads for the load which means you connect the load direct to battery which means there is no protection for over discharge or too rapid of discharge. I added a fuse to handle the too rapid of discharge.

It’s nice to have these boards so I can maintain the batteries to there max level. Recommend these to all who build boards for them selfs. I recommend these boards for maintaining the batteries