Batman is not beating Black Panther in a straight fight. He wouldn't beat him in a fight where they both have prep, as T'Challa is at least equally intelligent with greater resources. The only way Batman wins is with one-sided prep.
Tower of Babel involves Ra's stealing Batman's contingency plans and using them to take down the League.
Him standing up to Darkseid either involves using Radion (New God Kryptonite), the Hell Bat Armor (that he needed the rest of the League to help create), or rigging Apokolip's nukes to detonate. All of those are really impressive uses of one-sided prep, but he ain't beating any of those folks straight up.