Current time:0:00Total duration:1:11
What's going on: Chemical energy into electrical energy
- [Voiceover] So, how does this battery work? A battery is just a device that converts chemical energy into electrical energy. In each of these four cells, there are two reactions taking place, one that creates electrons and one that uses them, and when those electrons flow, that's what we call electricity. On the surface where the zinc is in contact with the saltwater, there's a reaction that creates electrons, and on the surface where the copper is in contact with the saltwater, there's a reaction that uses electrons. When you connect the top and the bottom of this battery with something that conducts electricity, then those electrons will flow through that object, like this LED. The voltage or electric potential that each cell produces is determined by the chemistry of this battery, and a zinc/copper cell produces a little over half a volt. So four of these cells makes a battery that produces a little over two volts. A red LED requires around 1.7 volts of power to light up. So your two-volt battery is plenty to light your red LED.