The Toyota Mirai hydrogen fuel cell electric vehicle has hardly been an international sales success, thanks to poor hydrogen infrastructure, expense, and polarizing design, but it proved successful to Ukrainian forces which scavenged parts from the hydrogen car to create the world’s smallest hydrogen bomb.
That name is also already taken. An atom bomb usually refers to the first generation of nuclear bombs that use only fission, e.g., those used in WWII. The hydrogen bomb refers to the second generation of nuclear bombs that use a chain reaction of nuclear fission and fusion to create bombs that are orders of magnitude more powerful.
For comparison, Fat Man was ~20 kilotons and the largest ever bomb (Tsar Bomba) was ~50,000 kilotons.