My 4x4 has had flat braid running the length of the deck with 10AWG soldered to the centre of it to run to the battery. It’s in flat heat shrink which passes under the battery box and foam covered grip tape. It’s been running like this for nearly 2 years and has been owned for the last 8 months or so by a guy who rides daily. It has done thousands of miles now, a lot of this off road. It’s taken a hammering and is as good as the day it was installed. Perhaps short runs that have had too much heat and solder wicking up them in an area where they move a lot could be recipe for disaster, the same would be true for silicone wire I would have said though.
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I might be completely missing something here but the video just seemed to show copper being heated up until glowing and then allowed to cool. I didn’t see a before/after demo of it becoming brittle.
Two issues…
Braid in a pack will never come anywhere near the temps required to alter the characteristics of copper. It would take monstrous amounts of current and the cells would go into runaway way before that from the heat transferred into them. Braid is often tin plated but the copper itself is pure.
You can’t harden pure copper with heat, it gets annealed instead, but it easily gets weaker from being flexed/moved.
AliExpress
Thanks for your reply, unfortunately it didn’t work.
I’m gonna connect it to the pc and go from there, but i wanted to see if anyone had similar issues and it there was a simple fix
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I believe @BenjaminF had a similar problem recently. Can’t remember if it was resolved
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Hey All. Planning my first brick pack build and choosing materials. It’s gonna be a 40 amp pack so am I off base in thinking that .015x 30mm nickle will handle that current just fine? If I understand what I’ve read so far, 0.2 x 30mm is good to carry close to 100 amps so I think I should be fine.
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Don’t threaten me with a good time.
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0.15x10mm pure nickel strip is good for between 14 (cool) and 21 (getting toasty) amps, so tripling that would give you between 42 and 63 amps for 0.15x30mm
plain nickel series connections aren’t recommended in flat packs though, due to microflexing causing stress points and failed welds or other issues over time. It’s fine for brick packs that won’t flex, but for everything else, it’s recommended to use something else for the series connections between cell groups. Usually several flexible silicone wires. Three 18AWG or two 16AWG would match nicely with that 40A goal.
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Did you ever work out if the last couple of groups were in trouble as well or if it was just one of them? Those voltages look good and cooked
it was just one of them, after replacing a single (3rd to last) p-group all the voltages started looking good.
Yes, I’ve built 2 other flat packs and both w silicone worm. This is for an e-bike and will be in a brick and in 4p so ampacity should be sufficient. Anyone ever built a brick in triangle formation?
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What fresh hell is this…
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Industrial battry building. The jig clever might inspire others
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This is pretty cool
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I know what it literally is, my comment was about what the person was doing.
Jig is fine. Everything else is unfortunate.
Is this why most factories don’t use fishpaper wraps? To save time?
Depends. Some do isolate between p groups, some use frames. Depends on the factory and what the order is spec’d for. I’ve learned more about factory production recently, as I’ve been working with an engineer for some more high profile battery building. I’ve been the local supplier and they need assembly guidelines for international production.
Anyway, my main issue with that video is the smacking around of the cells and the lack of isolation rings on the cells. And the cells being of mixed nature.
It screams of cheap and deceitful manufacturing that I’ve come to find in bottom of the barrel batteries.
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To be fair, I’m pretty sure the sped up video made the smacking way more intense than it actually was
The point is, you could use a jig like this responsibly. Also, you could easily have fishpaper rings applied to the group before this step, and if these were all in parallel, you wouldn’t need to isolate those cells, just around the entire outside.
Yep, exactly the same issue. @Sebas you need to install a different version of the app. Some versions aimply dont have the pin code screen at all (i know, great security feature 
). If you’re on Android you can get several versions directly from the LLT website. If you’re on apple there are two versions on the app store.
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Thanks!
I’ve seen that there are 2 versions, unfortunately one can’t change the settings
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