How do electric cars work? By harnessing the magic of magnetism.

From the battery system to regenerative braking, these are the basic technologies that power EVs.
a Ford Mach-E electric car parked in front of the woods in autumn
A Ford Mach-E electric car. Rob Verger

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To understand how electric cars work, it helps to keep in mind the ways in which they’re similar to regular gas-burning vehicles. They’re cousins from different generations, not machines from different universes. If you drive, you know the drill: Press down on the pedal with your right foot to get moving, point the vehicle where you want to go, maybe put on some music, and try not to crash. 

“An EV has four wheels,” says Chad Kirchner, the founder of evpulse.com, a news and information site about electric vehicles. “There’s a start button, there’s an accelerator pedal, there’s a brake. In a lot of ways, an EV—and the EV driving experience—is identical to a gas-powered experience.” 

That said, there are key differences in engineering, design, maintenance, and performance between electric cars and internal combustion engine (ICE) vehicles.   

Electric car battery system 101

To begin with, an ICE vehicle relies on a tank of gasoline or diesel to get the energy it needs. An EV, on the other hand, requires a battery system, which consists of a multitude of individual cells. And just like a gas tank, the battery cells store energy. 

“But [a battery cell] also produces power—and the power is a result of the voltage of that particular cell, and the current it’s able to output,” says Charles Poon, the global director of Electrified Systems Engineering at Ford, which makes the Mach-E, the F-150 Lightning, and the E-Transit electric vehicles. He describes the battery as the car’s heart.

Battery design in EVs will differ between automakers, and one of the main ways is the shape of their cells. To make things a bit more tangible, consider the Mach-E, an electric car that descends from a famous line of gas-burning vehicles that gave birth to the term “pony car.” The cells in the Mach-E are in pouch form, whereas other batteries in the market have cylindrical cells (Tesla uses those) or prismatic cells. A Mach-E battery system has hundreds of cells. 

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The lithium-ion-based electric car batteries can also have slightly different chemistries. For example, a Mach-E can come with nickel, cobalt, and manganese (NCM) batteries or lithium iron phosphate (LFP) batteries. The former are known for being able to hold power for longer and performing well in cold temperatures, while LFP batteries are less expensive and can charge up faster. 

How do electric motors work? 

The term AC/DC is not only the name of an Australian rock band, but also describes two forms of electricity: alternating current (AC) and direct current (DC). Both types of power are important for electric cars to work.

The electricity coming out of your wall outlet at home is in AC form, but batteries store their energy in DC form. Because of this, electric cars have a component known as a charger that takes the AC power flowing into the vehicle and switches it to the more battery-friendly DC. A quicker way to charge up one of these cars is by using a DC fast charger, which provides the car with juice in DC form, so the car doesn’t have to convert it. 

“It bypasses the AC charger [in the car], and goes directly into the battery,” Poon explains. 

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So the batteries store power in DC form, but there’s a twist: electric motors work with AC power. This means the vehicle has to transform electricity yet again, which it does using a traction inverter that converts the DC back into AC. “And then that is what actually ends up spinning the electric motor, producing power,” Poon adds.  

There are two key components in an electric motor: a stator and a rotor. The rotor sits inside the stator and rotates using the wonders of magnetism that kick in when AC power hits the motor. 

“We send what we call three phases of alternating current through a stator that has wires that are wound radially, sequentially, around the stator,” he explains. “And we are able to create a rotating magnetic field—so the magnetic field rotates, and it pulls the rotor along with it.” 

And voilá! After passing through some gearing, that rotation turns the wheels on your electric vehicle. 

While an ICE car has one engine, Kirchner, from evpulse.com, notes that electric vehicles in the market can have as many as four motors. For example, the rear-wheel drive version of a Mach-E uses one motor, while the all-wheel drive version uses two—one for the front and one for the back. At the other end of the spectrum, a Rivian R1T can have as many as one motor per wheel. 

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The pros and cons of driving an electric vehicle

Could you imagine if taking your foot off the gas pedal in an ICE vehicle magically made more gasoline appear in the tank? Something like that happens in an EV.

This cool trick is called regenerative braking, and allows drivers to start slowing down not by pushing the brake pedal as in regular cars, but by taking their foot off the accelerator. Don’t worry—that brake pedal is still there when you need it. In one-pedal or regen mode, things happen in reverse: the wheels turn the motors so they act like generators and send power back to the batteries. 

“You are actually taking the vehicle momentum and putting it back in as chemical energy into the battery,” Poon says.

Mach-E Chief Engineer Donna Dickson says one-pedal driving still remains an unfamiliar technique for drivers, but notes that it helps prevent wear on the brakes while also adding battery charge.

The power source is not the only difference between electric cars and ICE vehicles. There are other details that set the two apart. For example, Kirchner says that while combustion engines have to rev a little to make torque, EV motors make all of their torque from a complete standstill. This results in great acceleration. “Around town, even electric cars that you would not consider sporty by looking at them feel very quick, which makes them excellent city cars,” he continues. 

Another benefit of driving an electric vehicle is that they need less maintenance. There’s no need for an oil change, although their heavier weight means their tires experience more wear and tear. 

On the downside, you can’t charge up the batteries as rapidly or as easily as gasoline goes into a tank, but if you can charge at home, you have a unique perk: “You start every morning with a full tank,” says Kirchner. But that doesn’t always come as easy as it sounds. 

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“If you are an EV owner, it’s pretty much imperative at this point to have someplace to plug in and charge overnight,” says Paul Waatti, manager of industry analysis for AutoPacific. However, “there’s a good portion of America that doesn’t live in a single-family home.” People residing in condos, apartments, and other residential setups will have a more challenging time finding a charger to plug in their cars overnight. As for public chargers, Waatti says those networks are “very far off from being seamless at this point,” meaning there are too few and many don’t work properly.