Does this affect my battery output or the cells?
Really? The problem is that will break soon, and you'll have no power. Then, yeah... it'll affect your guns' performance. You should solder that ASAP, ONLY if you know what your doing or you'll ruin the battery. Either that or take it to a battery pace and have them do it. I recommend Batteries Plus in Citrus Heights
another issue is if the black wire also split which would lead to a short. Fix asap since shorting is bad :D