BMW Formula E Geneva 2019
Will tomorrow's battery technology be used today in Formula E?
At the Monteblanco circuit in Spain, behind closed doors and off the press, some of the world's biggest racing teams rolled out a new generation of electric cars for a two-day test.
Behind every driver, wrapped in fiberglass, hid the most advanced battery pack in the world. It was designed to run at high speed on rough roads in the next season of Formula E, a four-year-old all-electric championship that already competes with the Formula 1 as the most intriguing motorsport.
Electric cars are not ideal for racing. Although clean, they lack the roar of F1 engines and sound like a full-spin washer instead. Charging is also less easy than refueling with petrol so that riders get into new cars in the middle of the race.
But the hustle and bustle of electric cars has led the world's largest automakers, including Renault, Audi and Jaguar, to race in the hippest cities in the world, including Rome, New York and Berlin. F1 has a huge fanbase of 1,4 Billions, but has earned a reputation for being a congestion and not an overtaking, while Formula E has improved each season and has increased its audience from 65 to 200 million.
Porsche, Mercedes-Benz and Aston Martin all want to set up new teams. The driving force behind these successes is the battery technology that began in Formula 1. Williams, one of the F1's oldest teams, invented a flywheel system that absorbed the energy of braking and converted it into electric thrust by catapulting cars out of turns into the straights. Williams commercialized the technology before selling it to GKN, a UK-based 11 billion-dollar engineering group.
With wine, linguine and pistachio biscotti in an Italian restaurant in Paris, a group of politicians and motorsport bosses, including former Ferrari boss Jean Todt and European Commissioner Antonio Tajani, meanwhile agreed to introduce an electric version of the Formula 1 and become Williams commissioned with the construction of the batteries.
There were six months for a prototype and only one year for race readiness, but in the first season, each car traveled a distance greater than the Earth's circumference, powered by batteries that could hold an iPhone 13 for years in operation.
The improvements since the launch show the pace of change. Battery design is a compromise between power, range, and fire protection, but in four years, 137mph's Formula E engine speeds have increased to 186mph, while 17's range has more than doubled on 39 laps.
Each team is allowed to build its own engine and transmission, but each car has an identical battery that accounts for a quarter of the weight of the car Williams designed for the first four seasons. Then they lost the bid to McLaren, which had two years; The technology is developing so fast that the organizers of the races have shortened the contracts they award.
From energy availability to power loss, battery technology is an endless baffle on the subject, but the key variable is energy density: how much energy can cell manufacturers pack in a confined space? The technicians then have to compromise between the speed with which the cells release energy (high discharge rates add up to high maximum speeds) and the battery life (total range). Double the one and you halve the other.
Yet McLaren did the impossible by raising both. It has increased the number of cells per car from 165 to 209 and thus exceeded the weight limit, but also almost doubled the energy density. It makes the sport "faster and smoother," says McLaren, "eliminating the need for drivers to change cars during a race". How did it lead to such a big win?
Each battery contains a mixture of liquid metals that are constantly being optimized by cell manufacturers. Lithium and nickel have a high energy density, but heat up quickly and can explode or catch fire. Cobalt has a tight molecular structure so that the batteries can be recharged repeatedly without affecting the performance of the batteries, while manganese keeps the overall temperature low.
The chemical composition of the Formula E batteries is a closely guarded technical secret, but one possibility is that McLaren uses a nickel-containing concept with 811 chemicals, in which eight parts of nickel are used for each part of cobalt and manganese. 811 formulas are known but are considered to be years away from commercial production. An alternative explanation is that McLaren may have added a groundbreaking component: aluminum.
Aluminum batteries have a high energy density and fast charging times and are also not flammable. The disadvantage is the poor battery life, but adding graphite can solve the problem, according to Stanford University scientists. Vanadium batteries could theoretically give similar results, but fewer tests were performed on vanadium.
Does the evidence indicate that Formula E has turned to aluminum? Williams, who is looking for a solution to McLaren's system, told the FIA that the new batteries have had a high level of "degradation" which means they could struggle to maintain performance race after race. That would be the hallmark of an aluminum battery. McLaren says they can solve the problem.
Either way, aluminum could change the global battery market and accelerate the transition to electric vehicles. At today's prices it costs 2.287 dollars per tonne, compared to 15.235 dollars for nickel and 83.250 dollars for cobalt, which is a quarter of the price. It is also light-weight, fuel-efficient and can be sourced reliably from countries such as Canada and Australia, while Cobalt accounts for two thirds of production in the Democratic Republic of the Congo, one of the world's most chaotic countries.
Motorsport has always been a “test field” for new technologies that will be commonplace on motorways in two decades, say racing bosses. Other innovations being driven by Formula E are battery cooling tubes, an engine interference suppression device and brakes that act as chargers that take energy from the wheels and feed it back into the battery and win an additional lap for every four laps driven. The charging times are getting faster and faster: every car can now be charged in less than an hour.
But if aluminum is the unknown metal in Formula E's new batteries, it could be the sport's greatest gift to the automotive market. “It's amazing to see the progress that has been made in just four years,” said Jean Todt. "Doubling the range of the car and increasing the performance is a fantastic achievement."
ISE - September 2019
