Do you mean the straps or the heavy gauge cables?
If your doing anything with the terminals, I would replace them entirely. I prefer the "Car Audio" style replacements as they have better retention than the "parts store" Universals.
Something similar to this.
http://www.amazon.com/Link-BTN1-Neg...1392733654&sr=8-11&keywords=battery+terminals
You will also find a good selection of heavy gauge wire at your local Car Audio Shop. Just be careful, they have some powerful marketing strategies that make people think $3 a foot cable should be sold for $7-12. They will also have the proper terminals for the size wire you may need.