DENJIRO: Batteries come in many types, such as lithium and alkaline. But have you ever heard of an “air battery”?
GIRL: Air battery? Never heard of it.
DENJIRO: As the name implies, it uses air to create electricity. Let’s use this high-grade charcoal to create an air battery to see what it does. Inside this tank is salt water and aluminum foil. Let’s put in the charcoal. Now I’ll connect the charcoal and aluminum foil to a motor.
Nothing’s happening. I’m going to try putting in a different piece of charcoal and connecting it to the aluminum foil and motor like before.
GIRL: It’s spinning!
DENJIRO: The motor is spinning this time. They look the same, but one produced electricity while the other didn’t. The difference is the air trapped inside the charcoal. I’ll explain the mechanism.
As the aluminum foil dissolves in the salt water, it releases electrons. The charcoal easily conducts electricity, so the air inside it takes in the electrons. This creates a flow of electricity, making the motor run. Because it is a battery that uses air, it is called an “air battery.”
The piece of charcoal from before didn’t work because it had no air left inside. However, if I take it out of the salt water and dry it for a few minutes with a hair dryer, the air inside will be replenished. Now it can generate electricity again.
Have you ever heard of a charcoal battery? Soak paper in salt water, wrap it around the charcoal, and cover that with aluminum foil. This is also an air battery that generates electricity.
NARRATOR: Air batteries are small and can last a long time, so they’re used for hearing aids. By removing the sticker to let air in, it generates electricity. They’re also used for emergencies during natural disasters.
DENJIRO: I hope energy will bring you all happiness. Our magic word is "Happy Energy!”
24 дек 2020
