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design bars that are wide enough to maximize contact(surface area), just long enough to connect the battery terminals( you don’t want extra material swinging around; risks causing a short), and thick enough to support the amount of current that will be flowing through these batteries[5].
brass busbars are sometimes used, but they are much less conductive than copper and the EMS sigma 60 is probably a much better bet
Interesting stuff to read:
https://interplex.com/busbar-guide/
Questions
What is laser welding vs spot welding that we do - lots of websites mentioned laser welding to minimize contact resistance
Sources:
[1] Battery Module Concept Rev 1
[2] Battery Module Concept Rev 2
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