Copper busbar - electrical conductivity

ESK8 Electronics
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Hey!

I’m currently planning a batterybuild where I’ll use a ”Chaka-style” cell level fusing(https://www.electric-skateboard.builders/t/fishpaper-and-cell-level-fusing-use-it/35026)

But instead of a brass busbar I’ll probably use a copper one, and I stumbled across a copper sheet which looks good. But on the product info the electrical conductivity is measured in ohm/mm2.

Does anyone have any input on if this is a good sheet to use for this application? The product info states 0,024ohm/mm2 @ 50 degrees celsius.

I’m guessing it will still be way better than nickel but hey, maybe there’s a copper specialist in house :grinning:

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Oh. And the product info is in german :joy:

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copper is 4 times as conductive as nickel

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Yeah, I’m probably splitting hairs here.

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Not splitting hairs - copper is the metal of choice for conduction due to its low resistance and other physical properties, thats why you find it everywhere in electronics…

You will be fine

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if you want to split hairs go for silver!

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What thickness and width of copper are you considering?

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I usually for gold but in this case that doesn’t make any sense. :smile:

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Actually, gold-plated silver is the best conductor known at room temperature. Silver conducts the best and gold makes the best connections to other things.

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Gold doesn’t tarnish and yes the best conductor too which is why a lot of A/V electronics have a bit of plating

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0.5mm. The length of 3 18650 cells (I’m in bed and I an hesistant to go measure cells atm, my wife is starting to worry about my esk8 addiction) and probably 10mm in width.

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Walt what, I’m 100% sure my ’ol teacher said gold was least conductive between silver gold and copper.

Curse you swedish schoolsystem! Making me look like a fool…

Edit: I misread your whole comment, this I also blaim on the swedish schoolsystem. Makes sense with the gold plating.

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can i ask a question here without derailing the thread…

isn’t a certain level of resistance necessary in the metal of choice for bridging P-groups so that balancing occurs more thoroughly between cells on charge and discharge? i know copper is available, and i know that its far more conductive. That’s literally what coper is known for and we learn that at a very early age.

this question is not motivated by giant spool of nickel i have.

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Gold is the least conductive of the two, but it makes the best connections to other things. No electric can flow through it inless it’s connected in a circuit. So silver in the middle and gold plating works best :stuck_out_tongue:

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partly because it doesn’t corrode at all, making it ideal for permanent connections such as in home theater systems and other areas where signal integrity is paramount.

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Yeah edited my post. Goto stop posting stuff in bed :joy:

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According to some hasty Google-fu, 0.5mm copper has a resistance of 0.000847 ohms/square. For a 10mm wide, 50mm long strip, that would be 5 squares, or 0.000847*5=0.004235 ohms end to end.

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That’s the thought in my head too but I don’t know how to science it to really figure out :yum:

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yeah my artist brain is smart, but not so much science and math smart, just imaging and producing things from nothing kind of smart.

sometimes i wish i could hot swap the kinds of smarts i have, then i could leave myself dtailed notes in plain english when i’ve finished mathing a problem and need to art on it.

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Ideally you want the least resistance because any resistance would mean a voltage differential which would mean uneven discharge and/or balancing. At least that’s what makes sense to me.