Badgers keep there living area very clean, where as foxes dont, so if you see a lot of old bedding outside it more likely to be a badgers set, you can always check for footprints thats a sure sign of whos at home, after all the rain yesterday should find good tracks.
But Badgers and foxes can live in the same set if its a large one, i know of one where this has been going on for years, 9 that i am aware of, it is monitored though so i dont go near it to often , have the odd look now and again, where is the one you have seen i might know of it as i live not far from you.
Regards hiluxmk