10 Pcs 2S 7.4V 8.4V 8A Lithium Battery Protection Board BMS PCB Protection Board MOS 18650 Charger Module for Li-ion Lithium Battery with Nickel Strip

After soldering up the various connections, I couldn't seem to get it to work, using a multimeter there was no output despite the battery being fully charged.Connecting the battery upto the device, and then putting it on charge triggered the protection circuit into life, and the battery is now functioning as it should. Brilliant!

Bought these to make a custom 4s battery pack and wired as per the example but output doesn’t work. Thought I was doing it wrong but looking online at others I’m right and the boards don’t work. Too late to send back now, really disappointed

to tiny to break

May be small but used successfully to repair one of my Erbuer lights that I was on the point of placing in the recycling. Useful video on YouTube to help.

These were a good price and I was able to return a failed Erbaur work light to working order.

Charges well over the 3.7v battery recommended voltage (charge voltage recorded = 4.9v+). Not an expert but possibly pushed the correct current.

I have already returned five of these which were identical but supplied by another supplier. These have the same fault. If you connect them as shown they just do not work. However connecting the top side of the battery connection to the underside of the PCB makes it work. On closer inspection the through hole plating which should connect the top to the bottom of the PCB is not through plated. I assume DAOKAI get these from the same place. It is just poor quality control (if any) at the manufacturer. Most good manufacturers can auto check the connections after production, obviously these guys do not bother. I am keeping them because I know how to fix them.

The welding parts are too close and the margins not enough, when soldering the positive and negative margins, they are too close. Its better to solder this piece of protection board before connecting to the battery to avoid sparks and shock.