Meta: If you’re thinking about getting an electric vehicle and have ever wondered how do electric cars work, read this article to learn more about electric cars.
People who have concerns about the environment or who want to avoid paying high fuel costs are turning to alternative means of transportation. While some may downsize to motorcycles or take public transportation, those who need a vehicle are switching to electric cars. Many people have questions about these vehicles, like how do electric cars work?
Types of Electric Cars
Before getting into the mechanics of electric vehicles, it’s important to recognize the different models that are on the road. Four types of electric cars are manufactured by many of the major car companies today. They are:
- Hybrid Electric Vehicles (HEV)
- Extend-Range Electric Vehicles (EREV)
- Battery Electric Vehicles (BEV)
- Fuel Cell Electric Vehicles (FCEV)
Hybrid Electric Vehicles
The most common type of electric vehicle that car manufacturers are putting on the road today is Hybrid Electric Vehicles or HEVs. Some of the best-known HEVs are the Toyota Prius, Ford Fusion Hybrid, and Chevrolet Volt.
Like a conventional car, a hybrid vehicle has an internal combustion engine, but they also have an electric motor and battery for storing power. The engine works the same as they do in conventional vehicles with gasoline, or sometimes diesel, fueling it. The pistons in the engine move up and down, using the energy to combust the fuel.
That provides the car with the power it needs to run and turn the transmission, which turns the wheels. The electric motor in an HEV has batteries that produce electricity for the electric motor under the hood. Then, the motor turns the car’s transmission, which helps turn the wheels.
An electric motor in an HEV uses advanced electronic technology to act as both a motor and generator. Along with drawing energy from the batteries to increase the car’s speed, the motor can also return energy to the batteries as the car slows down. A hybrid vehicle also has a generator that produces electric power, which is stored in the batteries.
Parallel Hybrid Cars
The two sources of energy in an HEV are an electric motor and combustion engine. They can be combined in different ways to run a vehicle. A parallel hybrid vehicle uses both the engine and electric motor to turn the transmission at the same time. The transmission then makes the wheels turn. Along with the engine and electric motor connecting to the transmission, the batteries also connect to it.
Series Hybrid Cars
In a series hybrid car, the gasoline engine doesn’t directly power the vehicle. Instead, the gas engine turns a generator, which then charges the batteries or provides power to an electric motor that turns the transmission.
How Hybrid Electric Vehicles Work
When first getting in an HEV and starting it, the car runs on electricity. Then, as the car accelerates, both the electric motor and gas engine powers the car. If the car is cruising down a highway, then the electric motor stops running and the gas engine powers the car because it runs more efficiently.
When applying the brakes to slow down and stop the vehicle, both the motor and gas engine shut off. This process is called “regenerative braking.” In a conventional vehicle, braking creates friction, which in turn releases the energy as heat. In an HEV, regenerative braking captures the energy from braking and turns it into electricity. The batteries store this electricity for later use.
When idling at a red light, the “idle-off” feature in hybrid vehicles will shut off the gas engine, allowing the electricity to power the accessories that are on, such as the air conditioner and headlights. Then, when the light turns green, and the car accelerates, the gas engine will help power the car if the electric motor needs additional help to get up to speed.
To recharge some HEVs batteries, they need to plug-in to a wall socket or charging point. They are bigger batteries than those that are in hybrids that don’t plug-in. The electric motors in plug-in hybrids (PHEVs) are larger as well, which, along with the batteries, allows these vehicles to drive only on electricity for longer distances, about 10 to 50 miles. The most efficient hybrids have a switch that enables the driver to operate the vehicle on only electricity.
HEVs get excellent gas mileage with many of them getting 50 miles per gallon. A PHEV can go about 100 miles before the batteries need to be recharged, although that range may improve to 200 miles soon. In general, an HEV can go about 300 miles depending on the size of the fuel tank.
While HEVs put out emissions of about 40-75g/km of CO2 due to their internal combustion engines, PHEVs have smaller gas engines and are able to get closer to having a zero-emissions range. The next type of electric vehicle is the extended-range electric vehicles or EREVs.
Extended-Range Electric Vehicles
An extended-range electric vehicle, or EREV, is an electric car that has two or more power sources. Since it has an internal combustion engine and electric motor, it is also a hybrid electric vehicle. However, in addition to the electric motor, it also has a plug-in battery pack.
The main difference between an EREV and PHEV is that the electric motor in the EREV always turns the transmission to drive the wheels. Also, the internal combustion engine performs the duty of a generator by recharging the battery when the energy runs out.
The battery pack also allows an EREV to run longer when the gas runs out of the engine. Most of them can travel for about 40 miles before needing to refuel. The driving range of an EREV is about 125 miles or more due to the generator and a larger electric motor.
The Nissan LEAF is an example of an EREV, as is the Tesla Model S. However, the driving range for these two vehicles is vastly different. The LEAF can go 150 to 225 miles only on battery power. The Tesla Model S can go 235 to 315 miles on battery power.
The tailpipe emissions of an EREV is about 20g/km CO2, which is nearly half or less than that of an HEV. Most of the batteries used in electric vehicles, including EREVs, are lithium-ion batteries, which are recyclable if they can no longer hold a charge or if they sustain damage. Although they are the standard for electric vehicles, lithium-ion batteries are more expensive than other types of batteries.
Some electric vehicles use lead-acid batteries, but automakers tend to shy away from them because they are much heavier than lithium-ion batteries and not as good for the environment. Another rechargeable battery is the nickel-metal hydride battery or NiMH. These batteries have a better energy density, so they are smaller than lead-acid batteries.
Battery Electric Vehicles
Another type of electric vehicle is the battery electric vehicle or BEV. The BEV is a vehicle that only runs on electricity, so they don’t have an internal combustion gas engine, fuel tank, or an exhaust pipe. They are also known as pure electric vehicles and, since they don’t use a gas engine, they put out zero emissions.
Getting rid of the engine, exhaust system, and fuel tank also makes the vehicles much lighter, giving them better mileage range. The average range for a BEV is about 142 miles, which does not include the Tesla electric vehicles, which have ranges of over 300 miles, with the Model S getting 351 miles.
When the battery runs out of energy, then it needs recharging by plugging it into a wall socket or a dedicated charge point. Charging a battery can take 30 minutes to 12 hours. The time depends on the battery’s size and how quickly the charger works. A rapid charger may be able to give a BEV enough power to drive 100 miles in about 35 minutes.
Most charge points found at the homes of electric car owners are 3.7kW, which is a slow charge point, or a 7kW charge point that is faster. The time difference between the two charge points is almost 50 percent as the 7kW charger can fully charge the 40kWh battery of a Nissan LEAF in six hours. It takes the 3.7kW charge point up to 11 hours to fully charge the same battery.
A dedicated charging station isn’t necessary to supply the power BEVs need. A 240-volt outlet, the type that clothes dryers use, will fully charge the battery overnight. As electric vehicles become more popular, stores that sell gas are also installing charging points to recharge them. Some companies are installing them on their properties as well to keep their employees’ cars charged.
How BEVs Works
If you want to know how do electric cars work?, BEVs rely on nothing but electric power to operate. Their batteries supply the energy they’ve stored to allow the car to accelerate, cruise highways or city streets. While the vehicle is in motion, it expends energy, but when it’s idling at a stoplight, it automatically turns off to keep from wasting energy.
Compared to cars with internal combustion engines, BEVs and other electric vehicles accelerate better than gas-powered cars and feel quicker. Their ability to accelerate is because electric cars can produce nearly instant torque when pressing on the accelerator. Cars with internal combustion engines more torque are created as the engine’s revolutions, or RPMs, increase.
Some of the examples of BEVs are:
- Ford Focus Electric
- Chevy Spark
- Nissan LEAF
- Kia Soul
- BMW i-3
- Volkswagen e-Golf
- Toyota Rav4
- Tesla Model S
Fuel Cell Electric Vehicles
The fourth type of electric vehicle on the list is the fuel cell electric vehicle, or FCEV. It is also referred to as a hydrogen fuel cell electric vehicle because it mixes hydrogen and oxygen to produce electricity and power a motor. Even though they are electric vehicles, FCEVs have better mileage and refuel like conventional vehicles.
FCEVs only emit water vapor and heat when the hydrogen gas converts into electricity, so there isn’t any pollution coming out of the tailpipe. The process for producing hydrogen for fuel can lead to pollution, which includes greenhouse gases. However, even with using the worst source for hydrogen, natural gas, emissions can still be cut by 30 percent or more when compared to gasoline-powered vehicles.
Finding a hydrogen fueling station could be challenging for those who buy an FCEV because these cars are just beginning to show up in the United States market. Hyundai is introducing more FCEVs to their KIA and Hyundai models, including those sold in the US.
The Hyundai Nexo is an FCEV crossover that is rated in the US to get 380 miles per tankful of hydrogen. KIA will introduce a fuel cell model by the year 2020. Hyundai will also work with another car marker, Audi, to add more FCEVs to the market.
How FCEVs Work
To power, an FCEV, hydrogen, and oxygen combine in a fuel cell to produce electricity. The most common type of fuel cell used for this purpose is the polymer electrolyte membrane or PEM. In this fuel cell, the electrolyte membrane fits between a cathode, which is a positive electrode, and an anode, which is a negative electrode.
Hydrogen, or hydrogen-rich, fuel goes into the anode and oxygen, from the air, goes into the cathode. Due to the reaction in the catalyst of the fuel cell, the hydrogen molecules break apart into protons and electrons. Then the protons go through the electrolyte membrane to the cathode side of the fuel cell.
In the meantime, the electrons go to work powering the car by traveling through an external circuit. They recombine with the protons on the cathode side of the fuel cell, and they combine with oxygen molecules to produce water. The main difference between an FCEV and other electric vehicles, like BEVs, is the process of converting hydrogen gas to electricity.
When the tank of an FCEV needs replenishing, refueling the car or truck is done in the same fashion as a conventional vehicle. The driver goes to a fueling station that has hydrogen and uses a pump to fill the tank. However, unlike other electric vehicles, there is no long wait time for refueling. Filling the tank of FCEVs only takes about five minutes before the car is ready to drive.
FCEVs have other features to increase their fuel efficiency, like regenerative braking. When the driver slows down the car to come to a stop, the energy from the act of braking is captured and sent to the bank of batteries for storage until it is needed to power the car.
An advantage of using fuel cells is that they can be stacked together to increase power for larger vehicles, like passenger vans and buses. Also, FCEVs run quietly because they don’t have mechanical gears and they don’t use combustion to create electricity.
Another advantage of using hydrogen fuel is that it is available domestically and there is no need to buy it from other countries. Hydrogen fuel is available in the form of natural gas, which is abundant in the US, waste products, biomass, and water via electrolysis.
Biomass fuel is a sustainable and renewable source of energy as it is created from organic materials, which are usually waste. Some of the natural materials used for biomass include:
- Waste residues like scrap wood or the wood shavings from mills
- Forest debris
- Crops like corn, sugar beets, sugar cane or wheat
- Agricultural waste like orchard cuttings, corn stover, and wheat or rice straw
Using these materials and waste products would keep them out of landfills and put them to good use powering both commercial and consumer vehicles.
Maintaining an Electric Vehicle
Even though they have fewer, if any, mechanical parts, electric vehicles still need routine maintenance to ensure they stay running well for a long time. It’s important to have the brake pads checked to ensure the vehicle is safe to drive. However, since most of the energy from regenerative brakes goes back into the car as electricity, the pads last about twice as long as they do on conventional vehicles.
Make sure the tires stay in good shape too and use the manufacturer’s guidelines for rotating them. The tires will last much longer if they are taken care of just as you would on a conventional car. An electric vehicle doesn’t have any advantages or disadvantages when it comes to tire maintenance.
Some electric vehicles have a thermal maintenance system that uses coolant. The coolant level should be checked occasionally and topped off, or the system flushed like you would in a conventional vehicle. Also, electric vehicles use brake fluid and windshield washer fluid, both of which needs checking on occasion.
Reference the owner’s manual regarding brake fluid levels and top the washer fluid off when it gets low. During the winter, consider replacing the windshield washer fluid with a winter blend that has a lower freeze point than standard washer fluid.
Electric Vehicle Battery Costs
Like conventional batteries, electric vehicle batteries last for many years, but they do wear out. The warranties for most electric vehicle batteries are eight years or 100,000 miles, whichever occurs first. However, some manufacturers, like Nissan, offer additional battery coverage for the capacity loss. Nissan offers an additional five years or 60,000 miles.
When batteries need replacing, it can be a costly endeavor. However, battery prices for electric vehicles have dropped about 70 percent since 2010, so they are getting more affordable. In 2010, the cost of battery packs were about $1,000 per kilowatt-hour (kWh). The average price for battery packs now is about $125 to $150 per kWh.
The average size of batteries in electric vehicles are 40kWh, so they will cost about $5,000 to $6,000 to replace whenever they wear out. The cost is another reason why it is crucial to maintain a car or truck, so the batteries last as long as possible.
Insurance Coverage for Electric Vehicles
Although you can save money on vehicle maintenance and fuel costs for electric vehicles, insurance costs are a little higher than they are for conventional cars and trucks. The cost difference between the rates for electric and conventional vehicles run about 19 to 26 percent in California. However, the rates may be higher in other states.
The reason for the cost difference is the higher price of most electric vehicles and the higher cost of replacing damaged parts. If you’re driving an electric car or truck and have an accident that damages the battery, you’re looking at a replacement cost of at least $5,000 for one part.
That price doesn’t include damage to the body of the vehicle or any other parts, like a fuel tank or fuel cell, depending on the vehicle. To get the best rates on insurance for electric vehicles, don’t be afraid to shop around for it. You could save $400 to $500 off the yearly rate.
Federal Tax Credit
If you’re thinking about buying an electric vehicle, learn about the Federal Tax Credit that you may be able to get to ease the differences in costs. In 2019, the tax credit is worth $7,500. Along with using this to offset more expensive insurance costs, it can also help ease the pain of the bad resale values of electric cars.
Even though you may not buy a vehicle to immediately resale it, if you decide in a year or two to trade it in for a newer model, you may be shocked at the resale value. Electric vehicles depreciate at a much higher rate than conventional vehicles, and they can lose an average of about $5,700 per year over the first five years.
So, carefully consider if the extra costs will be worth the fuel and maintenance savings you will get by owning an electric vehicle, and then decide what type to buy. The options for electric vehicles of all kinds are increasing due to more demand for them.
So, now that you know ‘how do electric cars work,’ you may want to wait a year or two to see if the costs come down or go ahead and invest in an efficient model now.