Hi everyone,
I am new here and somewhat new to electronic hardware.
I have this RGB light that runs off of batteries. Recently it stopped working and I took it apart to troubleshoot.
Upon investigation, I narrowed it down to what I believe is a BMS (see attached picture).

Other info:
- The battery is a 3 cell 18650 in parallel to make 3.7v
- the battery is functional (tested with multimeter, accept charge and discharges)
- overall the unit will work when the 'bms' is bypassed
- the 'bms' is connect in series between the battery and mainboard

My question is, is this part indeed the bms and if so how do I go about to replace this?

Thank you guys so much in advance

 

Hard to tell, but that extra module may be a charge controller. It seems to have some pass devices (Q1/Q2) and some monitoring chip (U1). It may also be some current control device, to limit current output. Without part numbers, hard to guess what Q1 and Q2 actually do.
Without that device, it may be possible that you would overcharge the battery, damaging it, or run the risk of short circuiting the battery on output..

 

Hard to tell, but that extra module may be a charge controller. It seems to have some pass devices (Q1/Q2) and some monitoring chip (U1). It may also be some current control device, to limit current output. Without part numbers, hard to guess what Q1 and Q2 actually do.
Without that device, it may be possible that you would overcharge the battery, damaging it, or run the risk of short circuiting the battery on output..

Thank you sagor for your response. It does help me with understanding this.

So I can confirm it does charge when the extra module is bypassed as shown in the first picture. I did contact the manufacturer of the device and they did not provide support, unfortunately.

At this point, say I wired a 1s bms up to it to control the current do you think that would be ok? Or should I just junk the device and abandon trying to recycle it?

Appreciate it

 

If that device is a charge controller, or monitoring /control device, it may be dangerous to run your overall device without it. Improper charging of a Li-Ion battery can cause it to explode

 

If that device is a charge controller, or monitoring /control device, it may be dangerous to run your overall device without it. Improper charging of a Li-Ion battery can cause it to explode

Thank you for your help.