Almost every scorpion species is capable of eating a smaller specimen. Almost every species is also capable of consuming a molting tank mate.
The only specie I've heard (only once nonetheless!) of that will is okay in multi-age, molting communals, is T. stigmurus. I CAN NOT verify this information. I'm looking to do a communal 3 T. stigmurus after Halloween I think. And should have birthings happening shortly after Halloween. I will then observe and see what happens.
Other than T. stigmurus, you will possibly see cannibalism. The best thing to do imo, is to add lots of plants (fake or real), rocks, and bark. The more nooks, territory, etc., you provide, the less of it you will see. Oh, and keep them well fed. But always be prepared to loose one or two. If you are especially concerned about loosing any, avoid it in the first place.
Chaerilus celebensis is not communal at all i believe. I have also read that other Lychas sp will canabalize each other during molting. Basically everything nomad said was right on. There is always a chance of some one getting eaten. In some species it's much less than in others. C nitidus is another species that should be communal at all instars. Even in multi instar tanks.