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I don't see it as especially wiki-worthy.

The sizing is based entirely on steady-state convective cooling rates of fixed installation. None of the conditions apply in an EV, where bus bars are cooling the attached components and the environmental conditions vary widely.

Sure, the table is useful as a general guideline, but there are many other tables for general sizing. And most of the sizes listed on this table aren't likely to be encountered.
 

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Why do you feel that multiple thinner strips will carry more current? The EV battery pack doesn't have a significant AC component to it so skin effect shouldn't need to be considered.

I generally just grab this chart to figure out bus bar size or convert from metric wire size to wire gauge.
 

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Why do you feel that multiple thinner strips will carry more current? The EV battery pack doesn't have a significant AC component to it so skin effect shouldn't need to be considered.

I generally just grab this chart to figure out bus bar size or convert from metric wire size to wire gauge.
I am just going by empirical observation in that the welding cables (DC) have more and thinner strands, but maybe that is just for flex. I also note that the bus bars from TS and CALB are typically several thin strips held together with shrinkwrap... I am assuming there is a reason they do that rather than one thick bar.

I'm not an EE, so thats only my observation, no technical backup on this one.
 

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There isn't a fixed ampacity, per se, for copper busbars as it depends on way too many variables (as peggus just pointed out).

Of course, currents in both the motor and battery loop vary wildly in EV applications, even during highway driving, which makes it even harder to nail down the required cross-sectional area for the conductors.

That said, the (extremely conservative) rule from the NEC is 1.55A/mm² (1000A/in²) for pure copper busbar. This rule results in a rather low 30C rise above ambient, when a 60C or even a 90C rise might be perfectly acceptable in a given (non-NEC) application.

That said, this is a good sizing rule for the expected continuous current (e.g. - 300A on the motor side with the typical 9" advanced timing motor), as relatively long overloads of twice that will be perfectly acceptable (causing a 60C rise) while briefer overloads of 10x or even 20x that amount will be ok, too.

The ampacity of a busbar is ultimately limited by the allowable temperature rise (which can't be any higher than the melting point of copper). Consequently, a wider but thinner bus bar will have a higher ampacity than a thicker bus bar with the same cross-sectional area because the former has more surface area to shed heat.
 

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Yes, but the multiple thinner straps used on the bus bars from TS and CALB are stacked directly on top of one another and covered in heat shrink, negating any increase in ampacity.

I've built a few 120 volt EVs. I generally use 1/0 cable or 50mm^2 bus bar for the battery side and 2/0 cable for the motor loop. I've never had any problems with wire heating.
 

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I also note that the bus bars from TS and CALB are typically several thin strips held together with shrinkwrap... I am assuming there is a reason they do that rather than one thick bar.
Yep, but the reason is because it is more flexible/compliant than a single thick copper strap, not because it has lower AC impedance or anything.
 

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... I also note that the bus bars from TS and CALB are typically several thin strips held together with shrinkwrap...
This is to allow the bus bar to flex easily and not put strain on the battery terminals. Even when the battery cells are tightly bound together there is still some relative movement between cells. Especially in and automotive environment…
 
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