No Man's Sky

Encountered my first robot fauna today, and they don’t eat creature pellets, they eat batteries. Like, when I go to my companion registry, there isn’t a creature pellets icon theres an ion battery icon!

Is that only when I’m in proximity to a robot fauna, like it will automatically toggle back and forth? I’ve been running around for like ages on this planet and I haven’t seen it turn back to creature pellets. If I find just one more fauna I’ll have them all for this planet, and so far, all robots. Are worlds all robot or all organic?