Just dropping these here as they are so nice. @akhlut did a great job!
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Both of these have 10 numbers but youāre saying B0 to B10 which is 11 wires.
This sounds like an off-by-one error.
Also the diagram you posted is not correct, B0 should at the same tension (voltage) as B- and B1 should be about 3.5V higher to the positive side
So measuring from B- you should have (assuming all cells are at 3.5V charge level)
(eleven numbers, eleven wires) B0 - 0.0V B1 - 3.5V B2 - 7V B3 - 10.5V B4 - 14V B5 - 17.5V B6 - 21V B7 - 24.5V B8 - 28V B9 - 31.5V B10 - 35V
What is the voltage between the big B- wire and the black balance wire (B0) ? Do you have a photo of the bottom of the BMS? How about a photo of the plug the balance connector goes into?
I think battery negative first
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I thought someone might mention thisā¦ i wasnāt sure how to write it in a way that wasnāt confusing.
I left one leg of my multimeter connected to b0, then measured the voltage to b1, b2ā¦ b9, b10. I can confirm no voltage drop between battery negative and b0 ( the other end of b0 is soldered to the negative terminal lol).
Hereās the bottom (other side) of the bms:
This would help, but I donāt see anything wrong at the momentā¦but I donāt know which way the plug orients and I need to know to help any more
Out of curiosity I removed the shrink wrap of a cheap Chinese xt-90 splitter. I was kinda surprised to just find solder in there to bridge the gaps. Is this an ok method of doing it? I was going to make my own one of genuine xt-90s and was wondering if I should use the same method or just make a regular y harness using wires.
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Rainy day today so Iām making a battery.
All and any advice welcomed.
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What soldering iron do you use?
Antex 100W. Very quickly because itās a beast. Less than a second.
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Ok Iām looking for one since the one I just bought was awful. Where did u get it
ebay. This is just for big stuff though. Iāve got a smaller one for other stuff.
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Well ok I bought this
Looks almost the same but for some reason the tip deteriorated within like 10mins of soldering 
As for the spot welding. Itās not pretty but I donāt see anything alarming
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The Weller 100w has a temperature controlled huuuge tip, great for big stuff (terrible for non-big stuff).
https://www.amazon.com/Weller-W100PG-Farenheit-Soldering-Degree/dp/B07C43TSFK
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I donāt think itās necessarily a problem, but something to be considered. Some of the series connections are 2 x nickel, and others are wire braid? I suppose the nickel ones will just bottleneck the pack as a whole rather than causing some kind of uneven discharge.
And I know usually everyone does the parallel welds as first layer, series welds on top of those, but for me I find the nickel-to-nickel doesnāt stick quite as well as the nickel-to-battery. I think, I could afford to lose a parallel connection but losing a series weld would be no bueno. So I would do battery ā series weld ā parallel weld. Someone correct me if Iām full of shit.
And something I do when Iām making packs, I put tape on all exposed contacts that Iām not currently working on. I know youād remove all that for the photo shoot, but thought it might help someone.
I like the welding jig 
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The nickel is 12mm x 0.15mm so I thought that would be ample for the size of the pack? 1 strip should be good for 40A or am I way off?
Batteries looking good, Nickel should be enoughā¦ I bought some 15mm wide 0.2mm thick nickel.
Yet to put my DIY welder together.
I will be using one of these butane soldering irons
Yes this is acceptable.
I hope you dont plan on using that for battery welding. In my experience, they donāt get hot enough for that application. You have to leave it on the battery for too long. But thatās just my personal opinion on it.
Iāve got a butane soldering iron, not this model though. I donāt find it anywhere near hot enough for this though. I use the exhaust outlet for heat shrink!
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