A new idea came to my head about my same metal water batteries. Since there is water in the air and that water is as pure as distilled water I think there might be a way for me to treat the water in the air like the water in my cups. Sticking two plates in the air and the water thats between could make my same metal water battery. This could be what Tesla was talking about with his electricity from the air, he could have been tapping the water electricity due to the thunder and lighting.

The water in the air could be the reason why we get radio transmissions?

But this all just an idea as of now.