I have not had batiks bleed, but others say they do.
You simply test your fabrics by tearing off the selvage and putting it in hot water..if it bleeds, then wash it!
I have put up to 30 fabrics in one load with 2 color catchers and they came out fine!
Batiks are a tighter weave, so they do not ravel as much, but I still pink my corners! AND wash a gentle cycle!