Hey, I’m currently making a battert management PCB. I have a 3S LiPo battery that will connect to the PCB via a jst 4 pin connector. A black wire which ground, a yellow for cell 1, white for cell 2 and red for cell 3. The circuit will charge the cells equally at a continuous voltage and current. I am getting confused to how to map my battery connections to the connecter. I have attempted it in the image attatched but I dont think it is correct. Any input would be greatly appreciated.
If you export to PCB, you will quickly see if those NET NAMES have attached to those connector pins.
They look like they are not attached. Suggest something have the net names parallel to the wire and the wire extending beyond the net name.
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Hey thanks for the reply and advice. After exporting it to a PCB, 3 of the connector pins are ‘Batt_Gnd’ and one is ‘Red_Cell’ so I suspect I may have gone wrong somewhere.
Note in this sch, how the net labels are associated with the wires
advice - load the demos, you will see how to position net labels
additionally, this is well covered in the documentation.
and do not forget the required reverse energy diode on the LM317 due to the large C1.
Read the LM317 datasheet for info.
and, given you wont need the whole range of the 20k pots, suggest pad with a resistor each side of the pot and use a smaller value pot.
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You have three different Batt_Gnd. Remove two of them (one that’s basically same net as White_Cell and the other that’s same as Yellow_Cell) and leave the last one.
You need to double check how you are getting V+ and V- as all three sections are drawn as if they are connected in series.
You need a bulk V+ serving all three sections in parallel, redo Batt_Gnd so it serves all three sections, then re-check where you pick up the three outputs
I think the sketch below is what you need to shoot for?
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Hi there, I’m currently designing my first PCB which is a Li-ion 3 series (12.6V) battery management system that will charge the battery cells when a car is running. I am quite confused on where to start with the tacks, mainly the thicknesses as well as constraints of the PCB. I am plannning on ordering it from PCBWay.
Any input would be amazing as well as any links to videos on the topic that would be beneficial.
I have also attatched a picture of my schematic for reference.
Thanks!
Suggest ask these sort of thickness questions on EEVBLOG
Also : Kicad has a calculator tool
Then, when you have the information, come back here and we can help you develop custom rules in Kicad PCB that will enforce the PCB design rules and ensure you meet your objectives.
Just a quick question, there were several recommendations given to you on your last visit on Feb1 and I notice nothing has changed on the circuit, a couple of people offered advice including @glenenglish have you verified that you schematic is ok and ready for layout ? shame to get bogged down in rules if you have fundamental schematic issues IMHO 
At the cathodes of D4, D9, & D14 it looks like you have crossing wire junctions. That is bad practice because it is more prone to visual errors. Better to join the top and bottom wires at different horizontal positions if they are both connecting to the horizontal wire.
My theory of pcb layout is not to use a thin trace if you have adequate space to use a wider one, such as 0.5 to 1 mm. There may be some specific situations where this is not true but for most purposes wider traces offer slightly lower ESL, lower crosstalk and are less subject to physical damage. Of course also lower DCR.
Why not try a layout for one of the three channels and submit it here for comments?
Kicad forums are not design review forums.
These forums are for questions about tool usage.
My advice is build it, make it and see what did not work.
why not breadboard is up ? All those parts are able to be easily breadboarded.
That’s how real engineers do stuff. or used to do stuff.
You will never learn anything unless you make your own mistakes and figure them out for yourself.
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That is the slow way. Gotta be able to listen to and learn from other people. I would be much worse as an engineer if I were not able to do that.
If the O.P. is using KiCad for their design, I don’t see why we need to discriminate in that way. Also…I can imagine some discussions which might be “borderline” or a “tough call.”
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I honestly don’t think the circuit will work. The TL431 isn’t used in any way that I recognise. The schematic is badly drawn. The bottom tier would be better drawn right side up with the input voltage from the right, rather than with a folded GND rail. The three repeated blocks screams for the use of subsheets. Unclear what that subcircuit is about, some sort of threshold trigger?
It would be a waste of time worrying about tracks when there are design issues. And that’s even before breadboarding. So this topic is outside the remit of this forum.
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Agree.
The U5 reg. only outputs 10V, then there is the .65V loss on the current reg. U6 so, disregarding all the other stuff above ( no idea how this works ), no charging will happen.
The current reg. should be before the volt. reg. Go check some Data sheets and System Examples.
We’ll see you back on this forum when you have some Kicad questions. 
Edit: I had another look at the stuff up top. I think they are supposed to be some sort of regulators. Unfortunately, however way I look at them, they seem to be drawn incorrectly. You need to do some serious checking.
I have merged the second topic with the OP’s original topic as it’s the same project, and set the topic timer to close 24 hours after the redundant topic was raised.
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