Go to the settings manual and change the balance type from charge balance to static balance. This will have it actively balance without the charger, so it will bring it into the spec you set for the maximum difference between the cells. Just let it sit for a day or two and see where you end up.
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Since you seem to know a little more about this BMS functionality, what do you have your overvoltage settings at? I have mine at 4.2 but I think that I triggered overvoltage and it stopped taking reverse current when I was braking near full battery
The problem is if you set it higher, when youāre charging it lets the top cell get to that voltage and then waits for it to go back down
These are my settings. I had lowered the over voltage from 4.25 when I was doing the initial balance on the pack and never bumped it back up. I generally keep it in balance charging mode since the pack is still under 50 full cycles and doesnāt have much trouble keeping balanced. But if its outside the threshold after charging ill switch to static balance. Also lowering the switch on voltage to 4V, or lower, is beneficial that way it will balance for a much longer time span.
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Alright thanks that helps, Iāll compare to mine when I connect
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Lets chat about these 2 cellsā¦
So cell 1 is the one i blew last weekā¦ Iām getting into removing.it now to notice cell 2 which welded fine has a.similar discoloring or wetness under the wrapperā¦
As compared to all the othersā¦
Thoughts?
And naturally my multimeter is dead.for.some reason so.have to run out and get a new one here nowā¦
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1 and 2 both had chargeā¦which i find interesting for 1 being a blown cell that let out magical juiceā¦ i replaced both since i was there anyways but would still love anyones feedback on #2 based on the weird under wrapper appearanceā¦ pack is doneā¦waiting on bms and flux deck is basically ready for the road!
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Okay, so my cells and BMS came. Now Iāve just got to wait for my spot welder to arrive before I start making my pack. Hereās my revised diagram:
Thoughts?
Iāve been reading about how much nickel strip I actually need, and it seems like 1 layer (of 3 individual strips that are 0.2mm x 10mm) seems to be enough for the parallel connections (since the current is shared across all 4 cells), and 2 12AWG wires should be enough for the serial connections (where a lot of current will travel between battery groups). Is my understanding correct/are these amounts of nickel and wire safe for a 10s4p S30Q pack?
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Check out @b264ās post on conductor current ratings. I think thatās pretty well thought out. Just make sure your soldering is on point for those series connections. Also, in your diagram, the nickel is only spotwelding between each cell and not across the entire P group. I hope thatās not actually how youāre gonna assemble it and that itās just how you decided to draw it out 
And donāt forget the fishpaper in between!
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This. Inside each P-group the cells can be separated only with their PVC jackets, but each P-group needs to have fishpaper between those cells and any other P-group.
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I like how need is a link to the conductor current rating chart. 
so I wonāt direct you there as well.
yeah whatās with the diagram?
when you say 3 strips and then draw them like the diagram do you intend to lay it out that way?
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Iāve got my fishpaper too 
Sorry Iām braindead Iāve been digging through the forum all day; the three nickel strips on each battery group should be overlapping, my bad.
I looked at the thread earlier but apart from there not being any data for 0.2mm x 10mm nickel, I didnāt understand if the amount of current the nickel strips in total would triple in the potential of what it can handle if you welded 3 together (across each cell in a battery group)?
The closest sized nickel strip with the current spec on the chart is the 0.15mm x 10mm stripsā with an optimal operating current of 17a. My thought is that my 0.2 x 10mm strips can handle that much if not maybe more because of its extra thickness.
If one strip of 0.15mm x 10mm can handle 17a, does that mean 3 welded together can handle 51 amps? Or does that not make any sense (ya boy donāt get it )
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Does it mean that once I weld across the 4 cells with 3 overlapping strips, itās ācomfortableā operating current is only 18.89a? And the only way I could increase the ācomfortableā operating current of each battery group would be to layer extra strips of nickel (or some other conductor) over the first layer?
3 in parallell can handle 3x so yeah 51A.
but they have to be in parallell. not some form of overlapping series. which iām still worried your diagram might imply.
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yeah I didnāt think it through when making the diagram, I was planning on doing something like this:
Ok. thatās effectively in series. so youāre getting one layerās worth.
usually people put a strip across the entire pgroup.
then if they need more current capacity they put another layer on.
then to avoid soldering on the cells they usually do some tabs off of that to come up to the series connections.
and I havenāt touched on your original question about how thick and why yet :).
right now Iām wishing there was a filter this thread for images mechanism so I could find you some good reference pics quickly.
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Ahhh okay.
How does this look (as opposed to my misunderstanding earlier lol)?:
For how many layers to use?
Yeah thatās better. now youāll find that 3 layers is uncommon and possibly not needed because the next magic trick. the current is split between your two upstream series connections. so if the path to them is even then your nickel for pgroup to series points only has to carry half the current. roughly.
really you just need to think about the paths from the cells to the series connections.
so if youāre targeting 4cell * 15A = 60A exiting via 2 evenly placed series connections then you need about 30A worth of nickel. but it could even be 15A worth of nickel off each cell to the series connection.
so I was trying to give you hints of how to think about it. iām still only learned from reading myself.
I think you should find a picture of how one of the experienced battery builders in this thread do it for reference. then ask for confirmation on size of nickel for that layout. because layout would matter.
yeah by thick I meant in totalā¦ how many layers
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