How, if possible, can you make a Hydrogen fuel cell from materials you can find around the house? And no, I do not mean something that produces hydrogen, I mean something that combines it with Oxygen to produce Water and Electricity, like the kind in Hydrogen cars. I have looked everywhere and all I can find is how to produce hydrogen and where to buy Hydrogen fuel cells, nothing about how to make them.
This could be fun. Hydrogen fuel is water that has had electrical current run through it. So what you do would have to be fake, a representation. I would use a small fish tank empty but use the thing that makes bubbles. I would put a glow light that shines through water. This would represent the process of making hydrogen (electrifing water). A toy tanker truck that hauls to a toy hydrogen station and a toy car to fill up. Yep, fun.
Practical fuel cells can be pretty high-tech.