It’s better if the balance wires don’t cross until they exit the pack. They can all cross right there at the balance connector.
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With the way he has the balance cables organized its really hard to keep them from overlapping without a space in between, especially the ones in the middle.
I will sometimes do one side in the middle cover it with fish paper and then do the other.
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Exactly what @yelnats8j said. Also if i wanted to separate every balance lead wires would also need to be extended and that would just lead to a bigger mess of wires.
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Looks ok. Do you have any clearer pictures showing the spot welds?
Also I take it the side without the fishpaper under the fold is the negative pole. If yes then you are good. If it is the positive, you may have a problem.
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You want the area shown with the red arrows to be covered with fish paper. If the strips ever cut through the shrink wrap you will have a short.
It should be like this:
You welds look a little cold too.
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Ok will fix that when I get home
I usualy test the welds to see if I can pull then off and it wasnt possible.
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If the welds hold you are good, they just appeared a little cold to me but I could be wrong. I also uploaded a picture of what I meant with the fish paper
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Hmm welds are really hard to judge usually, all of the welds on my boss welder don’t look like their welded but when I try to pull them off most of the time it lifts the negative terminal of the battery
My settings are 2x 2 7ms
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Hello, I am at the stage of building batteria for my project. I would ask for criticism or catching errors that I could make during the design. I will use the Samsung 30t battery. I want to create 10s2p which will give me a total of 70A and 6Ah. I will use a spot welder and nickel 10mm x 0.15 for serial and parallel connections. In addition, the series wants to connect with a 10awg silicone cable or a 6 mm copper (pvc) cable.
I am still waiting for fish paper to reach me to perform the isolation of groups P. On the positive and negative sides will be insulated (in the local store I have access to 18650, will it be ok or better to get bigger?).
I will use BMS bestech 80a.
I would like to put the batteries in printed ABS handles (the pet will be better despite the lower resistance to temperature?)
Thanks for your help!I
What about this pack?
Not built by me btw 
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eskating? I have such a pack laying at home for a repair. Each serie has copper braided over the nickel. The only thing I am missing is heatshrink around the pack
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Yes it is. In my newbie eyes it looks well built. This is a friend of mines pack (heatshrink was removed to check bms) but i have the exact same pack on my esk8 with about 15 cycles so far, works great.
Copper braided over the nickel? Could you explain more?
to handle more current 
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It shouldn’t be running over a corner of nickel. The nickel could pierce the wire causing a short
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Kapton/polyimide tape is not as good as fishpaper, especially for abrasion on the edge of metal
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How did you attach the P-Groups together These dont seem good?