erh; i see a 15V dip on a 112A load. for a 6S pack that is hitting bottom (and beyond) 18V should be the CV, at 50A (rather fresh charged) they hit their limit. (18V) 50A is roughly 22C. Good to see they hold up though, but tourturing them like this will shorten their lifespan for sure!
You should def. use them in 2P in your application.