As mentioned already, the list is a pretty difficult one, as it does rely a lot on who is writing, but also on the current imagining of the character. For instance, if I recall correctly, at the time when Bronze Tiger beat Batman that easily, Bruce wasn't internally ranked as high in the martial arts within DC as he is currently, so that fight wouldn't happen anywhere near like that currently. Not to say that Bruce would automatically be the winner, but it would be a lot tougher fight.
By the way, I love the idea of the week and already have figured out a couple of posts I want to do. Batman related, I admit, but he has had some spectacular fights these past few decades.