Why do cars operate on 12V?

Question

So why 12V and not 18V? What’s with the different levels for cordless tools 12/18/24.

In: 4

Answer 1

With basic chemistry, it is pretty simple to create a 1.5V battery. So you will see many batteries operate on integer multiples of this.

AA/AAA batteries are 1.5V. 1.5*6 = 9V batteries (those big square ones). 1.5*8 = 12V (car batteries and other larger batteries).

12V is just a good medium between “useful” and “low enough power to not have the potential to kill”. It’s also nice to have a low voltage, as you can keep wires (and therefore cost and weight) smaller.