I agree with Doc, however it is always a good idea to go with the larger cable. I have found for relocating the battery in the trunk marine grade cable works very well. It is very flexible like welding cable and can be had in various AWG sizes and colors. I got mine from McMaster Carr
www.mcmaster.com When I located my battery in the trunk, went with 1/0 AWG catalog #6948K75.
Vince