Not all welding cables are created equal.
Yes, I have used welding wire for rear mounted batteries with great success. Just a couple of things to consider:
-Make sure the insulation is oil resistant and heat resistant up to 275 degrees.
-Be sure to increase the size due to the long run. As minimum use #1 although I used single O or better yet double OO in the racecars.
-Of course it must be multi-strand.
Scott
Fab Manager
Welders360