SCIENCE4 - The Promise of Electric Vehicles

Electric Vehicles (EVs) are of great interest today because of concerns about climate change, and the fact that gasoline-powered vehicle emissions are one of the largest contributors of greenhouse gasses that many people feel are causing global warming - thus the desire to make the vehicles on our roads as clean as possible.  Lower cost transportation and reducing our reliance on costly and limited oil are also of concern.  Some experts think that we are in the middle of a technology revolution, and in fact may already have reached a “tipping point,” in our capability to produce clean, cost-effective EVs.

I wanted take a snapshot of where we’ve been, where we are today, and what the future looks like.

Principle sources for this article include “Why Should I Care about EVs?” and “The Shape of Things to Come,” Car and Driver July/August 2021; “How do Electric Vehicles Work?”, Alternative Fuels Data Center; “Why Battery EVs have Raced Ahead of Hydrogen Fuel Cell Vehicles,” Automotive World, June 30, 2020; “Owning an Electric Car Really Does Save Money,” Consumer Reports, October, 2010; “Future of Electric Vehicles:  Why Electric Cars Will Take Over Sooner Than You Think,” BBC News, June 1, 2021; “Gas Engines and the People Behind Them, are Cast Aside for Electric Vehicles,” Wall Street Journal, July 23, 2021; plus numerous other online sources.

I’ll start with a brief review of the history of EVs and then discuss today’s EV vehicle types and how they work, an EV development timeline, issues and challenges, other considerations, and finally I’ll offer my conclusions.

Early History

Experiments and early prototypes of EVs began in 1828 when Hungarian priest and physicist Ányos Jedlik invented an early electric motor and created a model car.  This evolved to crude electric carriages, small-scale electric cars, and locomotives powered by non-rechargeable batteries, designed to be used once and discarded.

Rechargeable batteries, that provided a viable means for storing electricity on board a vehicle, did not come into being until 1859, with the invention of the lead-acid battery by French physicist Gaston Planté.  Camille Alphonse Faure, another French scientist, significantly improved the design of the battery in 1881; his improvements greatly increased the capacity of such batteries and led directly to their manufacture on an industrial scale.

What is likely the first human-carrying EV, with its own power source, was tested along a Paris Street in April 1881 by French inventor Gustave Trouvé.

English inventor Thomas Parker built the first production electric car in 1884.  This electric vehicle predates the first internal combustion car by two years.  Parker along, with Paul Bedford Elwell, founded the Elwell-Parker Company and went into the business of producing electric cars and trams for the city of London.

Electric car built in England by Thomas Parker, photo from 1895.

 

The first electric car in the United States was developed in 1890-91 by William Morrison of Des Moines, Iowa; the vehicle was a six-passenger wagon capable of reaching a speed of 14 mph.

There was huge interest in electric vehicles all over the world, as they were easier to operate than gasoline engines of the time.  They also didn’t have the exhaust fumes and vibration of gas-powered engines, and didn’t need gears and shifters. The electric car was also easier to start, as gasoline engines used hand cranks to fire up.

The decline of the electric car started when there were massive road expansions.  With more roads, people wanted to travel farther and faster than before. The disadvantages of the early electric cars - limited range, refueling time (charging), and top speed - were its downfall.  Gasoline became a lot cheaper too, with the discovery of large oil fields. This meant that it was more practical to travel in gasoline-powered cars than electric ones.  Electric cars simply didn’t have the range to compete with gasoline cars.

The early electric car manufacturers stopped making cars in the 1910s.  It was also at this time that Henry Ford’s mass production Model T took over much of the market share that the electric cars left behind.

Renewed Interest in EVs                                            

Between 1968-1973, gasoline prices soared, renewing interest in EVs.  Lower cost transportation and reducing our reliance of foreign oil were the motivators.  Automakers began exploring options.  In 1974-1977, Florida’s Sebring-Vanguard company produced 2,000 tiny all-electric CitiCars, inspired by electric golf carts and eventually used as postal delivery vehicles. 

 

The CitiCar had a range of up to 40 miles per charge and a top speed of 30 mph.

Interest in EVs faded again until 1990-1992, when federal and state regulations incentivized more fuel-efficient vehicles.  Automakers began converting some gasoline cars to electric.

EV development started to accelerate.  In 1996, GM released the EV1, an all-electric car.  In 2000, Toyota started mass producing the Prius hybrid EV automobile, where the battery was charged through the internal combustion engine and regenerative braking. 

In a traditional gasoline car, when the driver applies the brakes, the kinetic energy from the vehicle’s forward motion converts into heat through the friction of the brake pads against a disc or a drum. That heat dissipates into the air, a waste of otherwise useful energy.  A regenerative braking system is designed to capture the kinetic energy traditionally lost during coasting and braking, and convert it into electricity.

In 2006, Tesla announced that it would produce a luxury EV sportscar.  In 2009-2013, the Energy Department started developing a nation-wide EV vehicle charging infrastructure, involving thousands of charging stations.  In 2010, both the Chevy Volt (the first plug-in hybrid) and the Nissan Leaf (all-electric) were introduced.  By 2015, there were multiple EV choices available to consumers.  There are currently about 40 different EVs available, from about 20 different electric car manufacturers.

In 2020, world-wide EV sales had risen to about 3.2 million vehicles, about 5% of all automobile sales.  Tesla is the worldwide leader in EV sales and has sold nearly half a million EVs so far.

Global sales of EVs from 2010-2020.

 

Car and Driver magazine's EV car of the year, the 2021 all-electric Ford Mustang Mach E.

Today’s EV Types and How They Work

Today’s explosion of interest in EVs includes automobiles, trucks, buses, motorcycles, and more.  There are four basic EV types under development:  all-electric, hybrid electric, plug-in hybrid electric, and fuel cell electric. 

All-electric, hybrid, and plug-in hybrid EVs are on the road today.  They are powered by so-called traction batteries that store electrical energy to drove an electric motor.  They are designed to provide that power over a sustained period of time.  The most common battery type in today’s EVs is a lithium-ion battery, because of its high energy density compared to its weight.  Fuel cell EVs are only in an early stage of development.

The figure below is a schematic of an all-electric vehicle, showing its major components.  The table that follows the figure compares the distinctive components of three EV types to gasoline vehicles using an internal combustion engine (ICE).

Schematic drawing of an all-electric vehicle.

Distinctive components of representative EV types.

Component	Gasoline	All-Electric	Plug-in Hybrid Electric	Fuel Cell Electric
Primary Propulsion	Spark-ignited ICE.	Battery-powered electric motor.	Both ICE and battery-powered electric motor.	Electric motor powered by hydrogen fuel cell.
Fuel/Power Source	Gasoline tank filled from external fuel dispenser.	Plugged into external battery charger.	Gasoline tank filled from external fuel dispenser and plug for external charger for battery.	Hydrogen tank filled from external fuel dispenser.
Battery	Provides electricity to start engine and power vehicle electronics, accessories.	Traction battery pack for motor power. Auxiliary battery to power vehicle accessories.	Auxiliary battery to start vehicle, before traction battery is engaged.	Auxiliary battery to start vehicle, before traction battery is engaged to supply supplemental power to electric motor.
Electric Generator	None	(Some vehicles)	Generates electricity from rotating wheels while braking; transfers it to battery pack.	(Some vehicles)
DC/DC Converter	None	Converts high- voltage DC power from traction battery to low-voltage DC power for accessories and auxiliary battery.	Converts high- voltage DC power from traction battery to low-voltage DC power for accessories and auxiliary battery.	Converts high voltage DC power from traction battery to low-voltage DC power for accessories and auxiliary battery.
Onboard Charger	None	Converts AC power from external charger to DC power to charge traction battery.	Converts AC power from external charger to DC power to charge traction battery.	Converts AC power from external charger to DC power to charge traction battery.
Other Components	Cooling system, transmission, exhaust system, fuel injection system, fuel pump, fuel line.	Cooling system and transmission.	Cooling system, transmission, exhaust system, fuel injection system, fuel pump, fuel line.	Cooling system and transmission.
Exhaust Gasses	Yes	No	Much reduced.	No

  

EV Development Timeline

Many auto industry observers believe that we are in the middle of the biggest revolution in motoring since Henry Ford's first production line started running back in 1913.  And it is likely to happen much more quickly than we thought just a few years ago.  Some believe we have already passed the tipping point where sales of EVs will very rapidly overwhelm gasoline cars.

The world’s biggest car makers certainly believe in the near-term future of EVs. General Motors says it will make only electric vehicles by 2035.  Ford says all vehicles sold in Europe will be electric by 2030 and VW says 70% of its sales will be electric by 2030.  Jaguar plans to sell only electric cars from 2025, Volvo from 2030, the British sportscar company Lotus said it would follow suit, selling only electric models from 2028.  Mercedes-Benz expects plug in hybrids to account for 50% of volume by 2025, and by 2030, will switch to all-electric EVs. 

The United Kingdom has announced it will stop selling new gasoline cars in 2030.

These mind-boggling transitions are planned over the next 4 to 14 years!

We are experiencing a technological revolution, and technological revolutions tend to happen very quickly.  Justin Rowlatt, Chief Environment Correspondent for the BBC, compare the EV revolution to that of the internet:

“By my reckoning, the EV market is about where the internet was around the late 1990s or early 2000s.  Back then, there was a big buzz about this new thing with computers talking to each other. … For those who hadn't yet logged on it all seemed exciting and interesting but irrelevant - how useful could communicating by computer be? After all, we've got phones!  But the internet, like all successful new technologies, did not follow a linear path to world domination.  It didn't gradually evolve, giving us all time to plan ahead.  Its growth was explosive and disruptive, crushing existing businesses and changing the way we do almost everything.  And it followed a familiar pattern, known to technologists as an S-curve.”

 

Typical successful new product market share growth.

“In the 1990s the more tech-savvy started buying personal computers.  As the market grew, prices fell rapidly and performance improved in leaps and bounds - encouraging more and more people to log on to the internet.”

“The S is beginning to sweep upwards here; growth is becoming exponential.  By 1995 there were some 16 million people online.  By 2001, there were 513 million people.  Now there are more than three billion.  What happens next is our S begins to slope back towards the horizontal.  The rate of growth slows as virtually everybody who wants to be is now online.”

“We saw the same pattern of a slow start, exponential growth and then a slowdown to a mature market with smartphones, photography, even antibiotics.  The internal combustion engine at the turn of the last century followed the same trajectory.  So did steam engines and printing presses. And electric vehicles will do the same.”

EV sales are expected to rise dramatically.  By 2025, 20% of all new cars sold globally will be electric, according to the latest forecast by the London investment bank UBS.  That will leap to 40% by 2030, and by 2040, virtually every new car sold globally will be electric, says UBS.

The reason is thanks to another curve - what manufacturers call the "learning curve."  The more we make something, the better we get at making it, and the cheaper it is to make. That's why PCs, kitchen appliances, and gasoline cars became so affordable.

Issues and Challenges

Despite the optimistic plans and forecasts discussed above, there are many issues and challenges facing EVs before they can “drive gasoline-powered vehicles off the road.”  The primary challenges include EV driving range, electric battery capacity and charging time, and the supporting infrastructure of charging stations. 

Driving Range. The best of today’s EVs can go about 300 miles on a single battery charge.  People are used to gasoline vehicles going much farther than that on a single tank of gas, so increased range is the first challenge.

Moreover, the efficiency and driving range of EVs also varies substantially based on driving conditions.  Extreme outside temperatures tend to reduce range, because more energy must be used to heat or cool the cabin.  EVs are more efficient under city driving than highway travel.  City driving conditions have more frequent stops, which maximize the benefits of regenerative braking, while highway travel typically requires more energy to overcome the increased drag at higher speeds. Compared with gradual acceleration, rapid acceleration reduces vehicle range.  Hauling heavy loads, or driving up significant inclines, also reduces range.

Batteries.  Battery capacity (the amount of electric energy that a battery can store) is dependent on the type of battery and its physical size.  Today’s lithium-ion technology is reaching its limit. The next generation of batteries, made with lithium-iron phosphate and other chemistries, are in development now. They will extend vehicle ranges to 400 miles or more between charges, and enable batteries to last as long as 1 million miles.  In particular, the extremely long life of batteries soon to hit the market are likely to mean the batteries hold their value well enough to be resold when owners trade in their cars.  And the next-gen batteries’ long lives may let them be used in ridesharing businesses that demand cars that can take the pounding of near-continuous use.

Analysts warn that rising battery demand will constrain the supply of lithium.  There is plenty of lithium left to mine, but miners need to accelerate current mining plans.

To achieve even longer driving ranges, EV manufacturers use packs of batteries to attain sufficient energy.  The total battery pack is limited by the available EV volume and the mass of the pack.  There is a certain size where it’s not feasible to make it any bigger, because we run out of room, or are adding so much mass to the vehicle that other performance metrics begin to suffer.  Mass is the enemy of handling, acceleration and braking. The greater the mass, the harder it is to achieve good results on those performance metrics.

The time required to charge EV batteries is certainly a challenge.  For EVs, there are three levels of charging.  In Level 1, the car is charged by plugging the vehicle into a 120-volt AC home outlet via an on-board charger.  On average, this takes 17 hours to charge a car.  In Level 2, the vehicle is plugged into a 240-volt power source at home or an outside charging station.  This takes 3.5 to 7 hours.  Level 3 involves a standalone DC fast-charging unit based on a 480-volt system.  Charge times are 40 to 60 minutes, but these charging units are not geared for home installation.  Instead, consumers must take the vehicle to a standalone charging station, much like taking a car to a gas station.

Charging Station Infrastructure.  The importance of availability and type of EV-charging stations depends on your driving habits.  It’s less problematic around town in some cities, where perhaps 60% of the population with EVs travel within 15 miles every day.  You can get to work and back every day, perhaps several days, with a charge from a Level 1 or Level 2 station with no problem.  

Note:  The Tucson City Council has just adopted an ordinance to require new construction of one- and two-family dwellings to have a designated parking space with one 40-amp power outlet (Level 2) installed to charge EVs.

The big issue is long-distance travel, where charging stations are not always available.  Non-direct route planning, accounting for lengthy charging stops, and possibly waiting in line to charge are significant issues.  To say nothing about “anxiety mileage range,” the paranoia that the battery is going to run out while you’re on the road.

In March 2021, there were about 41,400 EV charging stations in the U.S., according to the Department of Energy.  Fewer than 5,000 are fast-chargers.  That compares with more than 136,400 gas stations.  Multiply the number of gas stations by the average number of pumps per station (you guess) and the inadequacy of the current EV charging infrastructure is painfully apparent.

In response, private companies and consortiums are installing fast charging stations throughout the U.S. This, of course, takes massive investments.  Utilities in California are investing more than $1 billion to build the charging infrastructure necessary for electric cars, trucks, and buses throughout the state. These kinds of infrastructure investments will become increasingly important for public transit agencies, businesses, and people who want to purchase an electric car but are unable to install a charger at home.

 

EV fast-charging stations in Pasadena, California, February 2020.

President Joe Biden is prioritizing a national EV charging network under his $2 trillion infrastructure bill, promising to have at least 500,000 of the devices installed across the U.S. by 2030. (The Biden administration has proposed a $174 billion plan to spur the development and adoption of EVs that includes money to retool factories and boost domestic supply of materials, tax incentives for EV buyers, and grant and incentive programs for charging infrastructure.)

Achieving an adequate EV charging infrastructure will take a mix of government and private-public partnerships that can involve local municipalities, businesses, and utility companies, as well as automakers and an emerging group of EV charging companies.

Other Considerations

Here are several other points to consider in evaluating the promise of EVs.

Cost. The cost of complex lithium-ion battery packs has caused current EV sticker prices to be meaningfully higher than traditional ICE-powered counterparts.  However, battery cell costs have fallen from $1,000/kWh in 2010 to $200/kWh in 2018.  New generation lithium-iron phosphate batteries should be even less expensive.  The expectation is that when batteries can provide pricing near the $100/kWh pack threshold, the EV market share will grow quickly.

Meanwhile there are numerous federal and state tax credits, rebates, and incentives available to make it easier for the consumer to buy an EV.

Besides the sticker price, operating costs are important to consider for EVs.  In a 2020 study, Consumer Reports found that much lower maintenance costs and the lower price of electricity compared to gasoline more than offsets the higher purchase price of a new EV compared to an ICE.  Most EVs are $6,000-$10,000 cheaper to operate over the lifetime of the vehicle than an equivalent ICE vehicle.

Another cost consideration is EV resale value.  Today, the average resale value of EVs and plug-in hybrids is less than 40% of the original purchase price, versus 50% to 70% on conventional gasoline cars.  Improved battery technology is lowering costs, leaving existing owners with overly expensive models that few people will want secondhand.

Performance Pluses.  EVs are whisper quiet compared to heavily muffled gasoline cars.  An electric engine generates instant torque, which means that EVs zoom off starting lines (much quicker that gasoline cars) and provide smooth, responsive acceleration and deceleration.  EVs also have a low center of gravity, which improves handling, responsiveness, and ride comfort.

Reliability.  EVs are simpler mechanically than gas-powered automobiles.  Their drive trains employ fewer than 20 moving parts, compared with hundreds for the gas-powered version.  And auto makers can use essentially the same layout of battery cells and motors to power a range of electric models.  This should lead to simpler manufacturing and higher reliability for EVs.

Safety.  For any electric car to be sold, manufacturers have to comply with specific design regulations that ensure that their vehicle is safe enough for drivers.  Evidence is growing that EVs are at least as safe as gas-powered cars.

The chief safety concern for current EVs is the lithium-ion battery, a potential source of fire.  Manufacturers are developing the corresponding safety features to lessen this risk.  EV batteries are mounted on EVs after passing severe safety verification tests such as crash test, watertight test, immersion test, and combustion test, and verification that it’s protected from physical shock.

Today’s lithium-ion battery is combustible and can catch fire; it has power cells that can cause short-circuiting if it is damaged.  However, lithium-ion batteries have a much lower risk of fire explosions than gasoline in conventional vehicles. To prevent external damage or short circuit, EV batteries are usually surrounded by a protective cooling shroud filled with coolant liquid.  In addition, to external cooling, all EV batteries are installed in an array of battery packs, rather than one huge battery to prevent damage from malfunction.

Tomorrow’s lithium-iron phosphate batteries are the safest type of lithium batteries as they will not overheat, and even if punctured they will not catch on fire.  The cathode material in lithium-Iron phosphate batteries is not hazardous, and so poses no negative health hazards or environmental hazards.  There is no danger of the battery erupting into flames like there is with lithium-ion.

Fuel cell EVs powered by hydrogen are still experimental and only being tested in low numbers on public roadways, with many issues of performance, cost, and safety yet to be resolved.  The two prime dangers from fuel cell and hydrogen-powered vehicles are the danger of electrical shock and the flammability of the fuel.  These concerns translate into design needs for the vehicle itself as well as the requirements for structures intended for the storage, refueling and repair of these vehicles.

Overall Auto Design Flexibility.  One of the greatest benefits of EVs is that EVs could revolutionize the way cars are built.  Automakers are expanding wheelbases and pushing cabins forward since EVs don’t need to be designed around a front-mounted engine.  That means roomier interiors and increased storage space compared with gas vehicles the same size.  Electric power trains need cooling, but don’t generate nearly as much heat as ICE, so large (cooling system) grilles are not required.

The EV of tomorrow could be just a giant skateboard. With tiny motors placed inside the wheels, the car could assume any form imaginable; any sort of seating or storage arrangement could be built right on top of this flat base.

Conceptual "skateboard" architecture for future EV's could include a flat floor.

 

Conclusions

EVs have made steady progress over the last ten years or so.  The commitment of purpose and money from auto companies and national/state/city governments to the future of EVs (literally replacing gasoline-powered vehicles) is particularly impressive.  Technology and engineering solutions in work give confidence to achieving satisfactory driving range; high capacity, safe batteries; and low cost.

All-electric EVs will emerge as the dominant EV type, but hybrids will be competitive near term.

The time required to charge EV batteries seems to be a “show stopper” in the sense that current long times (and the required charging equipment) imply a horrendously extensive and costly charging station infrastructure.  Perhaps we need a “Manhattan Project” to improve battery charging times.

With current planning, the supporting EV charging infrastructure is of major concern.  How long and how much money is it going to take to replace 136,400 gas stations?

Fuel cell EVs may turn out to be the “best” EV type.  But when will we figure that out, and would we scrap all those battery charging stations for an entirely different support infrastructure, hydrogen pumps?

A full transition to EVs will be costly.  A Morgan Stanley report in 2019 estimated that it could lead to three million lost automotive jobs and cost automakers tens of billions of dollars in restructuring costs.  Labor unions are calling for government-sponsored retraining programs to help auto-factory workers land jobs in the new EV world. Manufactures say that some jobs will change as companies bring more work in-house, such as building motors and battery components, and that there will be new work opportunities during this transformation.

 

Bottom Line: The promise of EVs is enormous:  long-driving-range, quick acceleration, whisper quiet, reliable, safe, low-cost automobiles that do not require fossil fuels or adversely affect the Earth’s atmosphere.  Let’s keep the momentum going; it’s worth it!