ELI5: Explain Like I'm 5

Thermogalvanic cell

A thermogalvanic cell is a type of device that produces electricity using heat. It works by using two metals that react to heat differently. When one metal gets hot, it reacts with oxygen in the air to produce an electric current, while the other metal stays cool. This causes the two metals to "push" each other, creating an electric current called thermogalvanic power.