Im in the process of building my pack for a segmented enclosure and thats going to be my first build. Going to connect serial packs with a silicone cable. Right now experimenting with solder joints and found out if you try to peel the nickel from the opposite direction joint is not really strong but if you pull from each end its virtually impossible to break with brute force. yes, i roughed up the nickel, used flux and tinned both ends before joining them. a short demostration
another option i found is wrapping the nickel around the cable and soldering it that way, similar to soldering bullet connectors. it seems to be very strong when i pull from left or right side of it. am i being too obsessive about this i dont know open to suggestions.