No, this isn't a fighting thing. It's what people do sometimes when they're excited or pumped up.
9 seconds sound clip from the Big Hero 6 movie soundboard.
You can hear this line at 00:43:51 in the Blu-ray version of the movie.
Quote context
[...]
- Yes!
- Fist bump is not in my fighting database.
- No, this isn't a fighting thing. It's what people do sometimes when they're excited or pumped up.
- I will add fist bump to my care-giving matrix.
- All right. Let's go get that guy.
[...]