The reports I've heard are:
The grooves in the base of the e-bow do not align with bass strings, thus it is more difficult (though not impossible) to get a steady, consistent placement of the bow at the right location over the string.
Due to their thickness, it is more difficult for the ebow to activate the strings; thus you are more likely to need to start off the note by a hammer on.
Despite these, it is possible to use an ebow on a bass, e.g. this video, however I'd expect there to be a more difficult learning curve in getting to use it relative to getting it to work well on a guitar, which itself requires dedicated technique practice.
I haven't tried it out myself (maybe the next time I'm with my bass).