Constructive criticism welcome 
Edit: more pics
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Make the copper connect to the nickel in the space between the cells, then weld it. That way you have better current distribution and you do not have to solder on the cells
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Use the correct size insulation ring. With how the copper braid folds over the side of the can, you are in danger of a shoulder short.
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I slid some adhesive fish paper in there. What do y’all think? Will the folder nickel cause the same problem? I swore I bought 21700 specific isolator rings…
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So I have been recording the voltages of my suspicious cells and it turns out that I’ve had at most 0.002v self discharge over the past 3 days. Most cells have only self discharged around 0-0.001v. It’s probably so little that my multimeter can’t accurately measure it. I’ll continue the test probably until I get my NESE hardware but I think so far they are good 
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Probably good. I can throw some 21700 rings in with trucks. I have mailing label printed and box ready fur AM.
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That’s well within the range of the BMS. Sounds fine
Hi guys I’m new here but been building batteries for a long time at savemybattery.fr
I find nickel is too resistive for the power we requiere on some batteries.
Do you guys have some advice on making packs using copper spot weld ?
I have a few spot welders, ranging from suncko to big industrial ones.
considering buying tungsten electrodes and .1mm copper to give a try.
I use boss spot welder for copper.
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I read your thread and watched your youtube demo ! looks great
What electrodes are you using ?
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Custom mostly. I have a sunkko as well
okay, I also have a boss spot.
what would be your advice on making my own electrodes ? ( if you don’t mind sharing your tips, could be usefull to others ! )
I am guessing tungsten and 60 degres angle ?
That’s really nice of you dude, but don’t bother. I already ordered some haha.
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i tested tungsten with no success. Copper tips are good enough.
All the info is at the sphere https://endless-sphere.com/forums/viewtopic.php?t=89076
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@Arzamenable I was just notified by Battery clearing house that the HG2 cells they were selling may be counterfeit and they are offering full or partial refunds.
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spot welding requires resistance. Thats why copper becomes more challenging to weld.
Nickel can definitely handle the currents, especially 0.2 and 0.3 thickness and the proper width strip. Layered nickel is worse than properly sized. We also have the ability to use stranded copper wire, copper weave strip and bus bars for series connections where most of the current exists
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What a bummer.
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Did you ever do a capacity test on your HG2’s?
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No, damnit. I was relaxing.
gets up irritated, to burn some cells in the garage
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