In the movie Batman Begins, there are lots of ways in which it proves to be a superhero film. Firstly, the first half of the movie is based around the origin of batman (where he came from) and how and why he became Batman. The reason for this is to let the audience know what they are watching, so the right people are watching the movie and will enjoy it. Origin stories are mostly about ordinary people suffering some a sort of transformation. Unlike some movies, the superheroes do not choose to become what they do. For example, Spider-man, he gets bitten by a spider which gives him special powers and abilities therefor does not choose to become what he does. But Batman on the other hand, does want to become a hero to save Gotham from evil and stop its corruption and ending.
Secondly, like all Superhero films they have to have an enemy these are called super villains. Batman has the Scarecrow and is typically the binary opposite of the super hero. His aim was to poison Gotham and drown it in the people's own fear. If there was no villain in a superhero movie there would be no point in it, as the main reason that superheroes exist is to fight crime and protect the people. 
Thirdly, Batman wears a cape, mask and a black armored suit. This convention is associated with the superhero genre and the audience would probably only need to look at the hero to know what genre the movie is. Every stereotypical super hero would use a mask to hide and prevent people from knowing their true identity (Bruce Wayne). This is to save and protect the people they love from harm. All superheroes have a theme, this is shown in the name, costume and colors. for example spider-man's costumes is the same color as the spider that bit him, his name comes from how he got his powers ( 'Spider' Man), and his costume resembles a spiders web. Similarly, Bat-Man's costume is black like a bat, his cape and mask have the features of a bat (wings and ears) and his name, Just like spider man's starts with the animal they are resembled too. Also super hero costumes and out of the ordinary and something we do not come across in our everyday lives, therefore they are easily spotted and are only associated with this genre.Lastly, like all superhero films the typical conventions are that they have extraordinary powers, skills, wealth and technology. Bat-man has abilities no other average person has. For instance he is very wealthy, therefor most of his 'powers' where bought. He bought a cape made out of special material that can fly, his suit that a bullet cannot pierce and the bat mobile. All these things added to his strength and ability to defeat the villains and their 'minions'. Without these abilities the hero would be too easily defeated, the same goes for the villain, if they are weak they could be defeated too easily and the film would be boring. So the hero always has to have a weakness to create suspense within the movie.
