Most of them do not fade. I don't prewash batiks, but I do wash the finished quilt in Synthrapol so that any unset dye gets rinsed away rather than bleeding into other fabrics.
If you are unsure, you can pretest a small piece of each fabric. Drop it into clear water, or wet and place on white fabric to see if anything bleeds. You can prewash anything that is suspicious.
All of this applies to batiks the same way as other fabrics.