not just described, Explained


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How a battery works

Batteries are all about chemical reactions

Batteries work because chemical reactions inside the battery cause electrons to be pushed and pulled round a circuit.  When all the chemicals have been used up then the battery is dead.

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The chemicals are normally two different metals which are immersed in an alkaline solution.  One of the metals tends to draw electrons from the other metal and this is what causes the electrons in the outside circuit to move.

It's important to remember that the electrons in the circuit are already there in the wires and don't basically come from the battery.

The battery is part of the circuit

The circuit runs all the way through the battery. But instead of free electrons flowing through the battery there are negative ions, which move in the same direction as the electrons, and positive ions, which move in the opposite direction.

back to Lesson 1: Electrical Energy