can't really say who wins definitely. If batman has prep and basic knowledge of tony, then he'll know he'll be dealing with a tech war, and he isn't at all at a disadvantage believe it or not. He may not flaunt his ability to access technology by flying around in a suit like stark, but he can and does use tech to address any particular situation that calls for it. The level of the threat pretty much determines the impressiveness of what he takes out of the bin.