I'm reminded of this every year during Shark Week - in the clip below, Adam West's 1966 Batman fends off an angry about-to-explode shark with a can of shark repellent spray. That scene was actually rather faithful to the early Batman comics, which show that the Dark Knight does, indeed, carry around a can of shark repellent with him at all times. You know, just in case.
So, Batman is hanging from the Bat-copter (on the Bat-ladder) and is attacked by an about-to-explode shark. He wrestles with it for a bit and tries a few ineffectual Bat-punches to the shark’s head and body, then grabs his Bat-radio and asks Robin to throw him down a can of Shark Repellent Bat-Spray. This is stored in the Bat-copter along with three other “Oceanic Repellent Bat Sprays” designed to fend off, in addition to sharks, whales, manta rays and barracudas. Too bad Steve Irwin didn't think to carry those.
There is, of course, a Lego re-enactment:
Kind of related: Mythbusters on Does "Essence of Dead Sharks" Work as Shark Repellent?:
More at Fact Fiend - Batman Really Does Carry Shark Repellent Spray.
Related:
Smithsonian Magazine - Shark Repellent: It’s Not Just For Batman Anymore
It was actually first developed during World War II in an effort to help save the lives of seamen and pilots who had to await rescue in open water
Here's the 1983 episode of The Family Feud: the cast of Gilligan's Island vs the cast of Batman.
Physics of superheroes: Batman's powers questioned by scientists.
Video and infographic: the evolution of the Batmobile and the History of the Batmobile Parachute Pickup Service Van.
The Evolution of Batman in Cinema: From 1939 to Present.