Help a new member wire BMS properly

Announcement - Help us fight the BOTS! Please report all spam including stuff in your inbox!


New member
Jun 19, 2021
Hello, I bought four 4 packs of 3.2v 100ah batteries from the following website:

So essentially I have 16 packs of 3.2v 100ah batteries and 4 100ah bms. They are made from 32650 lithium cells, brand new. The 4 pack bundle was meant to wire 4 packs of 3.2v batteries into series to get 12 volt 100ah. Each 4 pack comes with a 100ah BMS.

I do know how to wire them in series to get 12 volts. But I do not know how to wire the BMS. I emailed support and here is what they said:


Sorry we cannot offer any technical advice at the moment

The B- wires go to your battery main negative, the C- goes to your charger

Can someone clarify the above? So all B- goes to negative, but what about the positive?
Also, is there a way to utilize 4 bms on one single 12 volt battery 400ah?


Mar 14, 2021
Here is a diagram, many BMS come with a simple schematic like this. The positive goes directly to the load ideally via a fuse or breaker. This pic assumes you are putting all 16 in series for a 48VDC pack if you are only doing a 12VDC pack then just parallel 4 together + to + and - to - is parallel. The BMS wires can be thin but make sure the main wires are thick enough to handle the amps you plan to put through them, that's also where the fuse/breaker protects the wire if properly sized.