@bollen do you know how to relate the cross-section to the width? I’ve always seen copper braid sold by width.
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width * thickness, but like you said it’s mostly sold by width.
I got some 11mm x 1.2mm that should be good to 90A so seems to match with the list.
The page has a list with approximate width and thickness for braid made from 0.2mm strands here:
https://www.copperbraid.co.uk/flat-braid/
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What we really need is someone with a primary injection tester who is willing to be the resident tester for all this shit. I would be more than happy to send scraps of nickel and wire to be tested and validated under a real, measured load.
Im considering buying an electronic load myself, but most that I can find that are within my price range (low double digits) only go to 20A max.
Does anyone know of an electronic load that can go up to 30A at least, for testing nickel strip?
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You might be able to use one or more VESC for that, attached to motors.
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Oh shit. Dude. Solid idea. I will investigate!
These numbers were slightly revised upward after seeing this empirical data
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Please also investigate — while you’re at it — is the current capacity of the nickel linearly proportional to the cross-sectional area? Because I’ve assumed it is above, but I have seen some copper charts where it isn’t for wire.
Does 2.4mm² (0.2 x 12) nickel carry twice the current as 1.2mm² (0.15 x 8) nickel? I’ve assumed yes…
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Yes I have been wondering exactly the same thing. I have been using this chart for calculations based on cross sectional area, but Im skeptical of it so I always try to over-estimate how much nickel I use.
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Great demo
None of these charts truly mean anything without a length listed.
But the video is great to show that for the most part, we’re overly conservative.
I’ve been running 12awg motor wires and I’m not quite sure there’s any reason to. 12awg is more than sufficient for battery connections for most street boards
Actually given some of this data, 12 awg is the biggest wire we should have anywhere near a street board by far.
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This is a bona-fide fact.
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The other thing about big wire also is that’s it’s physically stronger especially for motor phase wires that will be flexing a lot.
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IMHO there’s nothing wrong with running overly conservative whenever possible. More copper, less resistance, less heat, less strain. We’re talking electronic bombs carrying our bodies over the mighty ground. While there’s a beauty in having a balanced build, there’s even more beauty nullifying at max any electric risk.
Not saying everyone should run 2awg wires, however even going from 20 to say 50% more headroom is appreciable and not a stunt.
Let’s not get people go 28awg all around because “it’s ok😃” and later eat shit and complain at the hospital. We already have enough with all esc failure shitshow to add wires errors on top…
Ex : 3.5mm phase bullet and tiny cables on Focbox is actually undersized for sake of price and space, even if we’re talking AC currents and not DC albeit very fast switching.
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Plus bigger cables = less resistance = less losses = more range 
Ofc it stops somewhere in thickness though.
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I would agree with that as a rough rule of thum BUT also consider if this is squished inside a battery pack or encloser not open free moving air I would 1/2 the value as a rough rule of thum
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I added some more popular nickel sizes, including these.
@tinp123 Do you think anything should be edited?
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Mooch is receiving multiple samples of nickel in various shapes and sizes so hopefully we can add to this wonderful thread.
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@Battery_Mooch Please, let’s share notes 
I think the chart up top has been edited maybe 10 times now
I just added 25mm, 30mm, 50mm 0.2 nickel but the numbers are math based only on cross-sectional area. I don’t know if there is an exponential component to it…
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Happy to. 
I’ll first be working on setting up a consistent test strategy for wire and strip and then testing a few samples to get some feedback from the community on what tests are really needed.
My biggest concerns right now are about how the test setup itself can affect the results. Ambient airflow, heat conduction into the test table surface, the heat sinking effect of the wires connected to the strip, unknown alloys being substituted without our knowledge, etc., all can affect the results.
Hopefully the methodology I’ve been thinking about works well.
What were the criteria you used to set the Optimal, Acceptable, and Poor ratings? Wherever possible we should use the same power/voltage loss thresholds, current levels, temperature increase limits, etc.
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Yeah; you can get as complicated as you’d like — even as far as adding columns and voltage drops and data and formulas and different temperatures and grades of metals and acceptable failure rates and temperature rises and vibration characteristics and weigh all those data against cost, even adjusting for current metal market prices (and that’s fantastic to have as supporting data 
), and we discussed a little bit above, if the chart has more information than that it seems to become less useful. The green yellow and red are 1/1, 3/2, 2/1 ratios
Really a quick “What size do I need here” chart is the goal. Too much information is actually often times worse than not enough, because it becomes more difficult to action. The goal is to speed up battery making, not slow it down 
But if it’s supported by a much bigger and more comprehensive set of data behind the façade, that would be fantastic, as long as it has a simple red, yellow, green or other easy to use frontend IMHO
The more options that are presented the more confusing it gets for noobs also.
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Agreed, I do not want anything much beyond Good/Bad. I make the same types of decisions for my battery testing. Comprehensive test reports are always available but all those are boiled down to my Recommended Batteries table for easy selection of a good battery without needing to deal with the technical stuff. 
I wanted to know more about how you set your thresholds to see how much our testing can be overlapped.
What are they ratios of?