The battery builders club

That almost looks cold you didn’t heat/tin the nickel enouth shouldn’t be balling up we’re it connects to the nickle

See how it flows in to the nickle not mataining surface tension

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I tin both sides, then I just added more material on top (it all flowed so a solid connection). It’s easier to get it pretty with smaller wires though

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That hole punch technique looking fineeee :ok_hand:

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You are a genius for that one

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What he :point_up: said.



@Halbj613, re-read this :point_up:

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looking a bit better?

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Maybe it’s just me but those look like they might be missing a bit of solder.

Also remember to tape up the p-groups you aren’t actively working on so nothing accidentally shorts.

This thread might also give you good ideas of what to aim for your pack to be like

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i put a ton of solder on them and it just kept building up on top
the connection is very wet and really tightly bonded

May i ask you regarding a battery i wanna build if this would be ok:
So i wanna make a 16s 4p battery with 27100 cells tht have a discharge current of 45a
When i spot weld the seriel connections with 0.2x20mm nicel strips do you think this would be ok or do i need to add additional copper wires between them?
Thx for your input

  1. Molicel P42a can only do that much current if you monitor their temperature. 25A, or maybe 30A is probably the max you should be running them at per cell.
  2. When choosing Nickel, I like to go buy this chart of data gathered experimentally with nickel welded to cells made by some guy on the e-bike forum.

So if you’re building a 4P battery, and expect 25A per cell max when drawing power continuously, you need the series connection to be good for 100A. From this chart we can estimate that 0.2mm x 20mm nickel should be good for about 36A max. So if your series connections are just pure nickel strip, then you should stack 3-4 layers of it.

This is why for high current packs usually people connect the series connections with regular wires or copper braid, and not just nickel.

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Ok great thx very much then ill definetly need some copper braid

Shua please watch this, I made this especially for you

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The amount we use seems much higher rated, I like using 10A/mm^2 and that seems to be on the very conservative end still

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What a community. People are looking out for you Shua.

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thanks mate gonna watch it later when i get home
thanks man

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Thanks @skyart really useful video
Def will keep that in mind for the future

Think my joints are quite good now but will take more pics and post here to confirm

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Someone get this man a glass of water or something! :rofl:

A+ tutorial, exactly how I do it.

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Don’t’ worry I have a throat clearing tutorial I’ll upload here

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This video is great! What wattage/temperature is that iron? Thermal mass is probably a big part of it too but I’m just curious.

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