Fascinating technology

New car shows Formula E technology reaching critical mass

The FIA ​​Formula E racing series has unveiled the third generation of its battery-electric racing car, which will be used next season. This new car will offer substantial improvements in performance and efficiency over the current second-generation cars used by the series.

An often stated goal of racing is to develop technology for use in production vehicles. We can see evidence of this in vehicles like the new Mercedes-AMG C 43, whose electric turbocharger technology is a direct descendant of those used in Formula 1 racing.

Promoting electric vehicles and pioneering electric vehicle technology was a stated goal for the Formula E racing series, but the initial effort probably did more to highlight the shortcomings of electric vehicles than to promote them.

With just 150 kilowatts of power, the first-generation Formula E cars in 2014 were barely faster than the entry-level junior series where aspiring racers start their careers, not rivals at world shows like Indy cars. or Formula 1. Worse still, they lacked the battery life to complete a race. Recharging them or swapping charged batteries was not practical, so the solution was to have the drivers stop mid-race to change cars with fully charged batteries!

Naturally, that did nothing to convince viewers that battery electric vehicles were a practical solution for their own driving needs. Mid-life upgrades increased power to 170kW and improved regeneration efficiency by 50%. For its fourth and final season, Gen 1 car power has increased to 180kW. All of this underscored the series’ success in developing EV technology, despite the cars’ obvious shortcomings.

The 2018 racing debut of the second-generation cars saw them boost to 250kW and a top speed of 174mph. More importantly, the Gen 2 car battery could last an entire 45-minute run without shutting down. The Gen 3 car will deliver real performance gains for the 2023 season, with 350kW of power and a top speed of 200mph.

The new car, built by Spark Racing Technologies with batteries from Williams Advanced Engineering, includes many exciting new details. For example, there’s a generator on the front axle that contributes 250kW of regenerative braking to help keep the car’s battery charged. The car has only small front brakes and no friction brakes on the rear axle, where the drive motor provides 350 kW of regenerative braking power.

As a result, 40% of the energy used by the car during a race will be power recovered from braking. That compares to 25% for Gen 2 cars. The Gen 3 car’s combined 600kW of regenerative charging is a big number. That’s because these cars can be recharged during pit stops, and their DC fast chargers are designed to pump electrons at that same 600kW rate. This compares to peak power for 350kW commercial DC fast chargers.

Another problem facing both modern production cars and racing cars is a seemingly inexorable increase in size and mass. The Gen 3 Formula E car bucks this trend, being shorter, lower, narrower and lighter than the Gen 2 car it replaces. It goes from 5200 mm to 5016.2 mm long, from 1063.5 mm high to 1023.4 mm and from 1800 mm wide to 1700 mm. The minimum weight, driver included, increases from 900 kg to 840 kg.

The changes produce a car that will be between 2 and 5 seconds per lap faster than current cars, depending on the track.

“Gen3 is the pinnacle of electric technology for motorsport applications and provides a laboratory for future mobility,” boasted Alessandra Ciliberti, FIA Formula E technical manager and Gen3 project manager. “We see it throughout the car with the improvements we’ve made over this generational leap,” she continued.

Ciliberti particularly highlights the advances in car batteries. “The state-of-the-art front drivetrain kit and battery cells capable of faster discharge with greater capacity than the current battery but with a smaller footprint,” she said. “It is much smaller and lighter than on-road equivalents and there is potential for this technology to be transferred and for manufacturers to apply it to their consumer vehicles.”

While the prototypes have so far only undergone limited testing, test pilot Benoit Treluyer was able to make a few observations. As a driver who has raced all three generations of Formula E cars, he recognized the improvements made by the current cars over the originals. “Gen2 was a good step. It was more powerful, no car swapping like with Gen1 with the bigger battery capacity and the handling is good,” he said. “It wasn’t a big leap forward in ride feel – mainly in terms of power and design – but Gen3 for me is where that very big step comes in.”

This is exactly what fans and riders are hoping for. “Forward traction and grip are key when racing the streets and that’s great. The downforce is also very good – you could really feel what was missing when we tested without various body parts.

Brakes are an often overlooked aspect of race cars, but the emphasis on electric regenerative braking in the Gen 3 car makes it a new area of ​​customization, Treluyer predicts. “You can play with the software to balance the braking feel. It gives riders more options and it will be really interesting for riders to try some unique things with the brakes – directional braking and more stopping power on certain corners of the car, for example,” he said.

An important factor to consider when relying on regenerative braking is that cars with fully charged batteries have no place to put that power, and so they can’t brake as hard as they can. can once the batteries have been discharged a little. “Batteries are full at the start and regeneration is harder after that, so the strategies will be completely different and the teams will go in different directions,” Treluyer said. “Some riders might start off hard and others might try to be more conservative.”

Anyone studying the transmission setup of the Gen 3 car, with its rear motor-generator and front generator, is surely thinking about the possibility of using that front motor to power the road. Ciliberti recognizes this as a planned development path for the Gen 3 car. Gen 4, we need to make sure Formula E stays at the forefront as a laboratory of future mobility.”

All of these changes mean that Formula E cars are no longer too slow and impractical to wow race spectators, and the cars are proving their worth as testbeds for improved EV technology. The Gen 3 cars look set to put on a good show for fans and impress engineers evaluating their technology for use in production vehicles.