That is probably over 1meter of length, and we use like 10cm max, so this chart is not really usefull
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is it? ah i never looked at the units at the top 
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Ok, well I’ve got two layers on there.
The cell holder limit width to 8mm.
so thats 2 layers of 0.15mm x 0.8mm Nickel
I ran 10 amps through a 6" strip (which is the max length I have on the pack) and it gets just slightly warm. WHen the car battery charges up Ill run a little more through it.
The breaking of welds occurs due to mechanical stress? I could reinforce the pack with fiberglass to get it remove even more strain from the welds
Yes, but not strictly bending type, also vibrational. P groups need to be able to slip around each other a little in order to accommodate the board’s flex as well as the board’s twist. Every deck flexes and twists, even if they say they don’t. I designed my witchblades specifically to fight flex and twist yet they still do and will pop welds like no tomorrow if i don’t build the packs a certain way.
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Hmmm ok.
I think I’m going to cut the series connections and redesign my layout.
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Incorrect! From the OG thread (scroll up to see the famous table)
Don’t you have like a meter total nickel in your packs? 
To be serious, only the current handling paths should be counted, so the bulk of the parallel connections don’t count (depending on how series connections are made).
Im pretty sure you understood it wrong because Im pretty sure its not the same if you push the same current over one piece of nickel strip one meter long and pushing the same current over 10 pieces of 10cm long nickel strip one on top of the other
I understood you, was just teasing a bit. Still, the table is for nickel strips in the scale we use them in battery packs, not 1 meter floating in air. Also the heat builds exponentially. Once it’s at the current where it gets warm, HOT HOT HOT is coming soon.
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Nickel welding may be insufficient.
It happened with my pack. If you charge in that situation, the cell will be unbalanced.
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Updated the design. The series cells are no longer attached on the cellholders. Allows for flex. The conduit wire is stiffer than a braid but will still easily bend.
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So I screwed up really bad. I was nearly done with my new build, getting ready for doing the first test ride today. Everything wired up nice and tidy:
I just wanted to put the BMS into the @lock housing that a friend has printed for me:
I was mocking things up to find out if I needed to drill some extra holes into the housing (I do). I disconnected the AS150 so that I don’t short anything. With that precaution taken I felt like there’s no need to be careful. I still had the balance leads plugged in though. Suddenly I heard some sparking and saw smoke coming up from the balance leads. Fortunately, it only took me a second to realize what was going on. I had one of the wires leaning against the connector like this:
I immediately removed it and started swearing for good two minutes what an idiot I am. Then I went to assess the damage caused. There was a lot of smoke so I was almost sure I will need to replace all the balance leads.
The short seems to have happened between the cells 7 and 9. The balance leads got so hot that it melted the shrink tubing:
I first unplugged the balance leads from the BMS and inspected the connectors. Nothing looked burned. Good. I then measured the voltages at the end of the balance leads. Surprisingly, the readings were as expected. None of the wires has burned.
I removed the shrink tubing to inspect one of the balance leads:
I can’t see any damage on the insulation. These are silicon insulated wires, which has probably saved me from making much more damage. Still, there was significant smoke and the tubing melted despite there was silicon insulation and kapton tape between the wire and the tubing. Could it be that I managed to get out without having to replace the balance leads?
It’s likely that the wires got damaged but what’s the worst thing that could happen? If the wires break completely, this will be immediately apparent on the cell voltage readings, at which point I’ll have to replace them. Is there any other risk? If the insulation got damaged, the wire could potentially short out with the neighbour balance leads but I can’t see the slightest signs of damage anywhere. Any thoughts?
The balance leads are 26 AWG silicon insulated wires. The short lasted a fews seconds. Maybe 3-4 secs. The parallel packs are 2P Samsung 40T, i.e. 70A max discharge.
BTW, following this incident I implemented a major upgrade to my DieBieMS. 
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that balance lead was acting as a fuse and burning.
right now that burned wire’s resistance is greater than the non-burned ones.
but since very little current (< 100mA) is being pushed through the balance leads, you may be ok.
but…i’d replace that balancing wire if able.
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It’s not terribly complicated to replace the balance wire but it’s still some hassle. The main problem is that I don’t know if I can unpin the crimp from the connector that came with DieBieMS. I could always cut the wire and replace the major part of it (only keep the few cm of the original one near the connector).
I wonder what could go wrong if I don’t do that though. I can get individual cell voltage readings anytime from the DieBieMS via Metr. As long as I keep an eye on it, I can’t see any risk.
true, if that balancing wire doesn’t rust off and you can sense it when it does, you should be ok. just stay on top of the health of the battery overall.
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I really like the DieBieBMS and the functions, Im also anticipating the Flexi BMS lite will bring the size and function for direct t discharge.
We just completed the 3rd evo falcon with the DieBieBMS. Silicone covered balance wires are a must, being mindful of the materials used in the construction of the pack will help. We discovered that a lot of material can protect the cells and groups and balance wires, etc. We also realized its bulky and traps heat. Putting the material where it’s needed and not everywhere makes a difference in the performance of the pack. We also know there are many ways to build a battery pack and really like the innovations and forward-thinking that the community thrives on.
Our 3rd evo falcon belonging to @Tello1969
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I always use nickel strips and also solder them to increase the mass and/or add copper jumper wires… Only the strips alone are just too risky in my humble opinion
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You are correct good sir, now a days nickel strip is no longer enough. If you combine it with a flat braided copper wire the current capacity is increased dramatically and heat (source of shorts) is less likely to occur and the nature of the build (bare bones) becomes apparent. The minimal use of bulky materials, the proper use of silicone covered wire and the additional copper braided wire in the construction results in a battery pack that delivers in performance and longevity.
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Torque board DD 4WD build? Awesome!
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Yes! With a touch from sender
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