Thanks you. I greatly appreciate this. I look forward to seeing the pictures.
Also try to make nice solid spot welds to prevent issues
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yea, those are nice beefy welds, evenly distributed. good point.
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In the meantime you guys have any good local US sources for adhesive backed fishpaper? I’ve found it in amazon but not adhesive backed
Well good on you for taking the hard decision to rebuild the pack. I think the cells will be fine to reuse if your not too rough with disassembly.
The thing that always freaked me out about some peoples packs is how close the nickel is to the - can where it welds to the positive terminal.
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here’s P group, fish paper both ends, then clear pvc shrink:
all cells have insulator caps, cut away pvc shrink, welded with tabs for series connection:
using copper strand for series connections, going to solder tabs to copper strand.
when pack is complete, each 6s6p group will be shrink wrapped again and slots cut through to allow for some amount of flex:
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It that hummie deck? Sweet. The only concern I have is carrying 6 cells worth of current through just 2 nickel strips: it’s probably way fine in real life but I’m super cautious. Would be cool to do this foldover with like a 3 cell wide nickel sheet.
Where did you get that copper strand. Probably more conducive, but do you think it’s as stable as the flat sheets?
my thinking is resistance increases over distance. the tabs you see here are about 3mm so at that length ampacity should be well above average amp draw. i mean, these cell fuses can do 20amp at short lengths so 10mm nickel should be able to handle it. this is without any experimentation though.
i wouldn’t run long lengths of nickel, like when making serial connections.
it’s going to get secured down, insulated with kapton, the whole pack will be pvc shrinked again when it’s complete.
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Does this make sense being rated for 40 amps?
Binge drinking and battery building.
The obvious solution is to switch to the 
's 
technicaly yes, but you’ve got nickel, just use what you’ve got.
if you’re concerned about long lengths of nickel, just double them up, and it doesn’t have to be stacked the whole length either. just double it up like half the length and it should up the ampacity.
parallel lines on the bottom are nickel strips.
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Thank you so much for all the advice and pictures
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I live in California so your suggestion tends to be my oxygen. The drinking is just comes back to bite me every year or so and when it starts it takes a long time to sober back up.
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Does it harm the cells at all if there was like a second long short/spark across two cells not connected in series? Was using scissors to remove some laptop and didn’t realize they had connected two cells. Quick spark. Still good cells? To be honest this happened a few times when I was inebriated as well just for brief seconds.
nah, you’re fine. small sparks, as long as there isn’t damage on the terminals, especially the positive (anode) end, are fine.
i usually have a glass of wine around at all times but maybe not be shitfaced while you work in explosive batteries…
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i hear ya, i’m on about my 5th build and each build is an improvement over the one that came before it.
i think most people’s first build is a bit of a mess then you go from there.
it’s great you’re doing your due diligence but there comes a point where you just have to build it. and it being something you build, you can always improve incrementally going forward.
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“As long as you don’t puncture a positive terminal”. When I was also a little out of it I decided to make a 10s1p, punctured the wrong part of the positive end. Started shootijg our flames. That’s partially why I’m so frightened to make my own stuff.
You can see the spot in the above pic where the problem occurred. Obviously I’ll be scraping this cell.
Grinding down terminals now. Re heat shrinking because most ripped off from the superglue
That whole shooting out flames thing is why I wouldn’t grind down the ends of cells. $160 dollars worth of cells is a hell of alot cheaper than a house fire. If you’ve got the money, let somebody else do the ghetto shit.
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So damn mad. Wasn’t paying attention accidentally stuck a battery facing the wrong way when I was stacking them in a box. Next thing I know the box has erupted in flames