Wrap Positive Cable w/ Battery Relocation?

I don't put anything over the cable inside the car except where it passes through a firewall or at the edge of cover panel that is under your door sill plate. I sometimes zip tie a set of cables together.

If I need to put anything on the cable, I'll split a piece of hose a zip tie it to the cable for abrasion protection.

Inspect the route for any sharp edges, IMO, that's where you need to focus attention.

Shrink tube would provide an additional layer of protection. I don't do that either except at pass through points.