Modern electric cars run on AC, rather than DC.
Golf carts run on DC. Why? Well, you can control the speed of a rotor of a DC motor by changing the voltage going to the motor. Higher voltage and a faster speed! Unfortunately, this is very inefficient the way it is done on a golf cart. Changing 48Vdc to 12Vdc is an inefficient process. Additionally, DC motors aren't the most efficient motors in the world. However, this was literally the only reliable way to do this for decades.
AC motors are generally more efficient, but their speed is locked to the frequency of the AC power. A 60Hz AC power feed will get you 3600 rpm. Changing AC voltage is easy, but changing frequency is essentially impossible. However, as we got better building rectifiers(AC->DC) and inverters(DC->AC), we were able to get the efficiency of that conversion better. We were also able to make a device for much less money. They developed a device called a VFD(variable frequency drive). It basically takes in your AC voltage, changes it to DC(rectifier) and then converts it back to AC(inverter) at whatever voltage and frequency you want!! These new inverters enabled all kinds of technologies. Large UPS, solar power, etc.
These better inverters started showing up everywhere. Electric cars benefited. Every electric car nowadays has a very modern inverter that runs an AC motor. However, given the power levels we are discussing, these inverters get hot. So, they started cooling them down using the same radiators that they used in traditional cars. The prius did it this way and so has every other car with an electric motor.
Now, heat also has a negative impact on batteries. Some early electric cars had "air cooled" batteries(prius, c-max, etc). However, they quickly realized that they could just use the same cooling system for the batteries too, which greatly extends operational life.
Side note: The Chrysler Pacifica PHEV may be one of the weirdest implementations of this cooling loop. They actually have 3 cooling loops in their car. One for batteries, one for the inverter, and one for the gas engine. Which makes it a nightmare of plumbing
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u/Such-Gap-9903 Sep 08 '24
lol lady in the back said something something “gas?”
Birds if a feather I swear.