it’d be an 18650 pack and I’d add the balance leads
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My phone charger has 4 ports 2.4 amps max each at 5v so that would be about 10amps of power if you merge them in 1 cable
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Have you tried charge only BMS and a laptop style charger before and didn’t like it?
Got BMS for $25 from forum member. 6amp charger for $100, also can get 4amp charger for $85 or saw 10amp for $130
I use a 50v adjustable power supply now and I’ll balance on the side with a “discharge balancer” and it works but would like a single plug option where everything is external from the board. I got an 8amp 50v for 60$ with a led screen and knob. I have a couple different ones but that was the cheapest.
how about 12 of these?
paired with a 5 v supply that does…(12x3 amps)…36 amps?
but I need to be reminded: how come I wont end up with a bunch of shorts if I hook 12 of these to a power supply and then to all my cells that are already in series?
Why wouldn’t you connect to BMS like this and use your power supply if it is cc/cv?
You won’t be able to use these unless you have a 26 pin plug for them to connect to. This is because these charger need the two wires to connect to each cell but bms’ and balance charger only have one wire in between each cell so unless you can find a way to connect it up like that this won’t work. And even then in my head it feels like the whole thing would short out because the positive of one little board would need to be connected to the negative of another since your cells are connected together. BUT FOR SCIENCE…
Edit: That sounded a lot simpler in my head lol
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yea I think connecting to a charging only bms sounds simpler. I have a couple of these coming: https://www.ebay.com/itm/Polymer-Lithium-Battery-Balanced-Function-Board-for-Balance-Charging-Protect/371906503493?hash=item56975ae345:m:mzsokMvxjwn0ybbwyeQcpbQ
could I wire the batteries so that they connect to a plug and that plug would just connect to this off the board? that sounds ideal. that way I could bulk charge as normal with all 12s in series and then plug this thing in to balance sometimes. No?
Or just put it on top of your pack, connect it and forget about it. Check the pack in a month intervals just to be sure it’s working properly :).
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Here’s something worth reading:
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Guess that would be possible but would be easier to keep BMS plugged in
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STOP! This won’t work! I’ve seen people try to do this before but because the cells are all connected in series unless the individual chargers are isolated the voltage keeps increasing and the TP modules die. Wish this would work but it doesn’t sorry! Unless your talking about a bunch of individual cells alone and charging them individually like @Blasto mentioned, nope.
yea I think putting the bms charging thing in the board is surely easier…but…how about if I used 12 linear power supplies instead of switching would that work?
No linerar are still non isolated you’d need to use 12 ground isolated PSU’s and at that point it’s gonna be easier to just use a BMS lol.
can you sum up for me why a linear supply wouldn’t be isolated? I’ve been researching and my understanding is very minimal. I thought linear supplies were just like transformers and I assumed all transformers were isolated as they have two coils which are physically separated. the more long-winded with sidetracks the better.
and what of @Quezacotl thing above where he uses even switching supplies all connected to one power source and one big battery in series I believe
From what I understand they are not isolated at all though I could be wrong. Also it doesn’t matter if they are because even at only 5V 1A the modules are going to get very hot and super inefficient. And @Quezacotl seems to be using isolated individual power supplies and still it seems very un reasonable and defeats the purpose of this all together.
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