After quite a bit of thinking and research, I used aluminum baubars in my 3P8S 840 AH build.
Couple of things, though - it is a stationary application, and I decided to not compress the cells.
Accordingly, the need for flexibility is gone - I spaced the cells so that the busbars won't ever see any stress.
Your cell terminals are definitely aluminum.
I think NoAlOx is a good idea - I cleaned both the terminal and the busbar with a flap wheel and NoAlOx, wiped it off to get rid of any grit, then wiped on a fresh coat od the goop.
My objective was to have some squeeze out to provide a seal around the busbar-terminal joint to prevent air ingress.
It uses 6101, which is hard to find. I used 6061, which has 1/3 higher resistivity, but at 200A, 1/4 x 1 would do - although you should have that area at the bolt hole.
BTW, I annealed the 6061 to soften it to provide a better opportunity for the busbar and the terminal to conform.