Why not put a charge only BMS in the charger and use mini USB-C for charger-battery connection, usb-c natively does 100W, it’s 24 pins allowing for up to 10S using 2 pins per S, with 2pins per main lead, or 12s using single pin and plenty left over for main leads
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that’s the one for me single plug balance charger kinda
Why would you put the BMS inside the PSU and have this gaint thing of wires and connectors coming out of the board?
I can think of two pretty good reasons
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So there is more space in the enclosure
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One bms can charge multiple different batteries
need not have wires coming out of the board and instead one of those plugs he’s talking about imbedded into the side of the board or something. i’d like to see how it looks on the board side
Lol thats more of a proof of concept…it works Also, all the wires would be detachable
Db15 for testing
A usb-c mini port can replace the balance connector, so all you have is usb-c to usb-c
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I feel like then it’ll make more sense to use a normal hobby grade balancer because of the better balance current and ability to change cell count. Also on the connector side it’s just more stuff that could go wrong, I prefer my GX16 connector on the side if my board and that’s it.
Hmm yeah a balancer would be better for charging perposes but this bms design is better for convience (as in small and compact)
but where you going to find a 12s balance charger if that’s what you’re talking about? the few I’ve ever seen aren’t available and crazy expensive.
this is off the board so less abusive and less likely to break is a big plus. and more room in the board as said.
Good point forgot about the 12S balance charger rarity lol. And BMS’s usually aren’t very big and can fit on top of the batteries or somewhere else that’s not in the way. Less abuse on the BMS, well yeah maybe but I really think the BMS is the last thing that’s going to break from abuse, your VESC is gonna die far before lol. Though I guess it depends from board to board.
and it’s a hobby. @scepterr thanks for posting this I’ll be doing it. next be looking for the ultimate plug that has…I guess I need 13 prongs and preferably can be sealed tight from water.
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Finding a suitable, small enough connector has been the sticking point
Xlr style 14pin
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SD28-12 or SD28-19 are good connectors. But the 12pin is only good about to 1A per wire. EDIT: Oh and yea, you need minimum 13 
I’ve already done it…
If you want one power supply though you have to use DC - DC isolators on each TP4056 otherwise you get a short…
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Would you be able to post a wiring diagram, I think I understand but I’m not 100% sure. Would it work if you were to wire the boards in series or would that also cause a short? That way you could charge with a 40v power supply
You can’t wire them in series with 40v because each TP4056 needs 6v max, so 40v will fry any that you have in series. You can however wire them in series with 5v power supply that can discharge at 8A or more as it’s the A draw that matters here… But this is then where you need DC-DC isolators (About £2 on ebay) on each one to isolate the power source, otherwise the single power source creates a short.
I thought it worked differently as in say with leds each is 3v max if you put two in series you could use 6v to power them and so on. Does it not work the same with these modules?
Just remembered if you going to charge a battery pack through balancer leads with multiple chargers connected you will have a problem, because between cells its not real ground, its + of cell before and those small chargers have B- connected to ground so if you have multiple chargers your going to shorten the circuit
Just finding the bits I want to hear.
But here he says he needed another supply for each
If could use one supply for all twelve modules in parallel that would be great. What u think?
You would need DC isolating modules for each one, but it could be done.
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