It's probably a Red-bellied Black Snake but there's no red visible whatsoever and the image is not clear enough when blown up to clearly see any other distinguishing features. Whilst the solid black colour and body form strongly suggest a 'Red-belly', colour is not a reliable identifying feature, as some brown snakes and tiger snakes can be black and melanic forms occur in many species. Do you have any other photos you could add?
Thanks Nick. The addition photo helps and is actually better than the first shot, as I can see the head in profile. There's something distinctively Red-belly about the form of the head in that shot and there's a very subtle indication of a brown snout that's characteristic of RBB's.