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Lithium 18650s protection board 6s (want to use 4s)



I have a 6s protection board in my possession.

I am in a hurry to build a 4S battery for a protect.

Is there anything I can do to my 6S circuit to convert it to a 4s?

I mean.. solder the pads of B5 and BY together etc? Not too sure how these things work.

I just want the batteries to have undervolt protection !

I have attached the type of a protection board!




Well-Known Member
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It is Chinese so there is little information about how to connect it. It does not limit the charging current so an additional charger circuit is needed.
I think its 2.5V over-discharge voltage detection is too low, my Lithium battery manufacturer says 3.0V to avoid damage.


Sorry mate, I think your confusing my question.

I want to know if there is a way to use this 6 string battery protection circuit with only 4 batteries.

I don't have room in my project for 6 battery!
Only 4 can fit!
I want to know if this circuit will continue to work with only 4 cells


Well-Known Member
Most Helpful Member
Many other BMS circuits show how to connect batteries. Learn how to speak Chinese and phone the maker of this one how to do it.
Oh, it is so cheap that the maker is unknown.

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