According to Heroic Hollywood, he’ll be acting like Batman as well:
Batman has a bone to pick with Waller.
You see Batman is totally against the concept behind the Suicide Squad, in fact he warns Waller that he will hold her personally responsible for any innocents The Joker & the rest of the Suicide Squad kill. A warning so stern that he has to visit Waller personally to deliver the message.
There will also apparently be scenes with Bruce Wayne, but those details haven’t come out yet. So it sounds like Batman’s role in Suicide Squad will be quite a bit more than just a glorified cameo.