During the Civil War, Batman was called in by Captain America to try and knock out Iron Man for the final battle. After studying a history of Iron Man armors for about 5 days, Batman attacks the Ironfuher with all he has, surprising him at night in New York City in his Tower after disabling security and alarms, so Iron Man can not get help from She-Hulk. Ms .Marvel or another Pro hero.
Iron Man, however, has a stash of his old armors around, capable of automated deployment and a fully functional suit at the beginning of the battle. He also is willing to use lethal force on Batman, because he is not Captain America or another hero whose death would be a public relations nightmare