The vehicles of the future are going to run on motors and batteries, this is the promise car manufacturers are giving us. A new generation of vehicles have been unveiled, hailed as eco-friendly and efficient energy consumers. On the surface, it seems like a great choice; we will worry a bit less about our carbon footprint, no periodic fuel station trips, and almost no noise pollution, all the attributes associated with internal combustion engines (ICE). It is a pretty good choice, maybe a bit too good.
History of the competition between EV and ICE
Before the dirty and grimy fossil fuel cars, we had the clean and aristocratic battery-powered vehicles. In the 1830s, Robert Anderson introduced the first battery-powered electric vehicle. The battery was a large stack of voltaic cells, a zinc plate and a copper plate with an acidic solution between them and this reaction converted chemical energy into electrical energy. They were non-rechargeable and very bulky. The electric vehicle was more of a demonstration than a viable product in that period.
In 1859, Gaston Plante invented the world’s first lead acid battery. The biggest feature was its ability to recharge. Electric vehicles grew in promise as an alternative to animal-drawn carts. Many modifications and advancements later, the lead acid battery was finally commercialized in 1886 by Luxembourg scientist Henri Tudor. Electric vehicles at last had momentum behind them as the ‘carriage for the future’ with patents from Thomas Parker, William Morrison, Andreas Flocken and companies such as Detroit Electric and Baker Motor Vehicle Company.
The year 1886 was the beginning for ICE vehicles due to the first patent awarded to Carl Benz for his gas powered vehicle. Both of these technologies saw rapid improvements in the late 1880s to early 1910s. ICE vehicles were loud, smelly, and starting the engine was a stunt in and of itself, the engine’s crankshaft needed to be manually rotated to start combustion. This process is called hand cranking. Hand cranking was dangerous because the engine could suddenly kick back, causing the crank handle to violently spin backward and injure the operator’s hand or arm.
The two thrived in parallel, with EVs having a bit of an edge, all the way up until 1912, Charles Kettering invented the electric starter. The crankshaft could be rotated using an electric motor. Ironic isn’t it? The electric vehicle was sent into a coma due to a small electric motor, that is why when your car battery is low, your engine doesn’t start.
Figure 5: Timeline of EV and ICE competition.
Henry T. Ford’s famous moving assembly line completely sealed the deal for electric vehicles. Massive commercialization of ICE vehicles meant no market share for electric vehicles, and so it was sent into a deep slumber.
As the saying goes, when America sneezes the whole world catches a cold. In 1973, the OPEC oil crisis began. It exposed the dependence Americans had on foreign oil, oil that ran their entire economy. Electric vehicles were brought out from coma and research began anew.
Zero emission vehicle mandate
The largest turning point for EVs came in 1990, the California Air Resources Board (CARB) introduced the zero emission vehicle (ZEV) mandate. A brief summary of its features are as follows:
- Large automakers had to sell a percentage of their vehicles as ZEVs. Inital targets:
- 1998: 2%
- 2001: 5%
- 2003: 10%
- Large automakers were defined as companies selling 35,000 cars per year in California. Companies like General Motors, Honda, Toyota, Ford, Chrysler, Nissan, Mazda fit the bill.
- Vehicles qualifying as ZEVs had to produce zero tailpipe pollutants and zero exhaust emissions.
- Manufacturers had to meet a minimum number of credits to continue selling cars in California. Credits could be earned by how well a vehicle performed. Parameters like range, charging capability, emissions performance were taken into consideration while handing credits.
The credit system was the single biggest feature pushing automakers toward spending on research. California could get away with this mandate due to the large market share they had over vehicle purchases. There were more than 25 million registered cars in 1990 located in California alone. The credit system was designed to push research into electric vehicle technology. A company had to earn a minimum number of credits to be allowed to sell in California. The most important feature was that credits could be bought and sold between companies. A company ‘X’ has 100 credits to their name, meanwhile the minimum amount is 120. A company ‘Y’ has 150 credits in their account. ‘Y’ could sell 20 credits to ‘X’ which will allow ‘X’ to keep selling cars in California and give them more time to research on newer technologies. Many companies opted for this method to generate profits. Tesla made a fortune using this strategy since they only sold electric vehicles, allowing them to amass an excess of credits.
Companies pushed back against this mandate but they had a very big market share to worry about. States like New York, Massachusets, Oregon, and Washington also adopted these standards with time, making innovation necessary. Limitations can produce great solutions, the General Motors EV1, Toyota RAV4 EV, Honda EV plus, were some of the solutions given.
Modern resurgence of electric vehicles
The biggest barrier to EV adoption was the fact that lead-acid batteries were very poor in energy density, with a value of 30-50 Wh/kg. Using some quick calculations, we can determine the mass used for an electric motor. A small 1990 motor of say, 20 kW needs to run uninterrupted for 2 hours. The total energy required is the product of power and time. Total energy becomes 40 kWh. Dividing this with the energy density of lead-acid battery, lets say 40 Wh/kg, gives me 1000kg. 1 ton just for batteries is insanely excessive. For comparison, 1990 Toyota Corolla had a curb weight of 1019 kg. Your car would weigh as much as your battery pack. Incorporation of lead-acid batteries was impossible for cars acting as average city vehicles due to their inaccessibility.
Nickel metal hydride (Ni-MH) and nickel/cadmium (Ni/Cd) batteries were popular due to their higher energy density of 75-80 Wh/kg and 30-70 Wh/kg. They were slight improvements over lead-acid but not the solution to the weight problem. The Toyota Prius, the defining hybrid vehicle for generations to come, utilized Ni-MH batteries to great effect. The Prius made the public trust electric motors in vehicles.
It’s a good thing that the solution for pure EVs was around the corner.
In the 1970s, Stanley Wittingham had invented the first rechargeable lithium ion battery. It used a lithium metal anode and a titanium disulphide cathode. It was unstable and posed a fire risk. This version of the battery could not be sold, but it laid the foundation for further developments.
The 1980s brought a new advancement, John Goodenough had proposed using lithium cobalt oxide as a cathode instead of titanium disulphide. This increased energy density gave another boost to lithiumn ion batteries, but they were still unstable, lithium metal is very reactive and can be a huge risk to public safety.
1985 saw the safety issue being solved with Akira Yoshino’s carbon anode. Shifting away from lithium metal opened the gateway to commercialization starting with the Sony Group launching the first lithium ion commercial battery. After this milestone, electric vehicle research was taken seriously bringing in the Nissan Altra in 1998, the first EV to use Li-ion batteries exclusively.
Li-ion boasted 100 Wh/kg energy density in 1991. Li-ion was in its infancy stage during this time. The technology was not trusted. Ni-MH had decades of research before and was chosen as the battery as it was more mature and far safer. Lithium ion still faced overheating, recharging, and economical issues. Lithium ion was too expensive for the average consumer. The cars utilizing Ni-MH batteries were getting outperformed by far cheaper and efficient gasoline cars. The only upside EVs had were quiet operation, lower maintenance, and zero emissions at a far higher price tag.
Table 1: Toyota RAV4 EV v/s ICE
| Specification | Toyota RAV4 EV (2002) | Toyota RAV4 II 2.0 16v VVT-i (2002) |
| Powertrain | Electric | 2.0L Transverse |
| Battery Type | Ni-MH | – |
| Battery Capacity | 27.36 kWh | – |
| Range | ~150-190 km | 647 km |
| Power | 68 hp | 148 hp |
| Top Speed | 125 kmph | 185 kmph |
| Weight | ~1400-1500 kg | 1220 kg |
| MSRP | ~42,000 USD | ~20,000 USD |
| CO2 emissions | ~60 g/km | 211 g/km |
A small company known as Tesla (okay, maybe not that small) unveiled the Tesla Roadster in 2008. This brought a big turning point (what is it, the fifth one by now?) in modern EV adoption. The Roadster unveiled itself as a serious luxury sports car. Tesla treated its car as an electronic item and not as a car, working on improving on-board electronics like battery monitoring systems, cell balancing algorithms, thermal management, incorporation of advanced power converters, etc. It took a lotus elise chassis and fitted it with their proprietary EV drivetrain. This approach allowed them to focus on electronics more than aerodynamics. Li-ion energy density had been increased to 180-200 Wh/kg.
Table 2: Comparison of Tesla v/s other sports cars in its price range. (Reference: Ultimate Specs)
Present day market share
Since the Tesla Roadster we have got many cars for each market segment.
The boom in the electronics sector has a massive contribution to the widespread adoption of EVs. Advances in power transistors (remember when this blog talked about semiconductor devices?), power electronics, control systems, memory modules and energy storage devices have allowed EVs to be welcomed with open arms. New companies are giving competition to a space dominated by household names. Sports and hypercars have Rimac Nevera, Pininfarina Battista, Longbow Roadster, Nio EP9 competing with Maserati GranTurismo Fulgore, Lotus Evija, Porsche Taycan and the like. SUVs have their own flagship models, especially the Indian market with Mahindra BE 6, XEV 9e, Tata Nexon, Tata Harrier, Kia EV6 among others. All of these cars boast the idea that luxury and power is green and accessible. Li-ion energy density has reached 250-300+ Wh/kg.
EVs make up 1 in 4 cars sold globally. Considering the amount of times EVs were sent spiralling into irrelevance, it is impressive how they emerged to compete with ICE vehicles which dominated for decades. This shows that the green and clean slogans and messages are working correctly. The idea that EVs are a better alternative compared to the heavy pollution generating ICE vehicle has penetrated deep into our collective mentality. Is this really the case? There must be some cost to all of this. Let us find out in the next part.
Frequently Asked Questions (FAQ)
Ques: What is the relation between advancements in batteries and adoption of EVs?
The energy stored in batteries is akin to your fuel tank. Battery energy density allows us to calculate the number of batteries required for an electric vehicle to operate in an adequate fashion. Old batteries had low energy density, more of them had to be used to give out sufficient energy which increased the weight of the car. New lithium ion batteries have high energy density allowing us to put in less number of batteries for the same operation.
Ques: What is the Zero Emission Vehicle Mandate?
The California Air Resources Board introduced the Zero Emission Vehicle (ZEV) mandate in 1990 to reduce air pollution and encourage the development of cleaner vehicles. The policy required major automakers selling cars in California to ensure that a certain percentage of their vehicles produced zero tailpipe emissions. Manufacturers earned “credits” for producing EVs, with more advanced vehicles receiving more credits. The mandate pushed companies such as General Motors and Toyota to develop early modern EVs like the General Motors EV1 and Toyota RAV4 EV.
Ques: Why do EVs have CO2 emissions?
Electric vehicles produce zero tailpipe emissions, but they can still be associated with CO₂ emissions because the electricity used to charge them is often generated using fossil fuels such as coal or natural gas. These are called “well-to-wheel” emissions because they include the entire energy supply chain rather than only the vehicle itself. EV emissions therefore depend heavily on the electricity grid of a country or region.
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