Need more info.
- What’s the orientation and design of the pack?
- What’s the purpose of adding copper versus stacking nickel?
- Have you done the maths and come up short with the current carrying capacity of a shingle sheet of nickel?
I’ve not done the nickel-copper sandwich myself but imo it’s typically unnecessary as it doesn’t afford any advantages over stacking nickel that are well-demonstrated. There are, however, several drawbacks. Your Kweld will be taxed and at full jules in order to get good welds. This obviously will make things much more laborious. Lots of heat, stress on components and your lipos. It also remains to be seen how the welds will hold up long term.
This might give some ideas but tbh, I think nickel is the way to go until we have evidence that copper is worth the trouble.