Ordered a couple cells today for some new packs.
Hope this box looks impressive enough to help me forget about the state of my bank account.
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I don’t have any way to check for capacity but so far over the past 24 hours they haven’t changed at all. I’m probably gonna give them a week to check for self discharge.
Definitely evenly distribute the off cells
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Its pretty impressive 
but mine usualy come in 2 boxes
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Next time you’re using heat sink glue. I learned something.
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Evolve 30Q mod, LHB style:
Every piece of nickel or solder next to balance wires isolated with hot glue + kapton, my favourite combo 
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Kapton tape
no i suck i haven’t figured out how to get it to talk to me over uart or usb yet
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you have the packs wrapped in insulation but you run balance wires across bare terminals?
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There is kapton between balance wires on sides and cells. I know kapton is not meant for insulation, but there won’t be any hard forces on sides of battery.
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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