For years in Formula 1 there has been a growing collaboration between engine manufacturers and fuel suppliers, synergies that will tighten even more in 2026 with the arrival of E-Fuels and biofuels. In Formula E we are witnessing a very similar dynamic, in which manufacturers are becoming aware of the importance of collaborating with partners specialized in the field of E-Fluids. An example is the collaboration between Shell and the Nissan Formula E team, two entities operating as one team to climb the ranks of the championship.
The importance of E-Fluids
When we talk about E-Fluids we refer to two different types of fluids: the E-Transmission Fluidi.e. the lubricant for the mechanical parts; the thermal fluidnecessary for cooling the electric motor and the inverter. In Formula E, the electric power that can be supplied by the battery is limited by regulation. However, by optimizing lubrication and cooling it is possible to reduce the power lost to friction or heat, with a double benefit. The mechanical power that reaches the wheels increases, but it shouldn’t be overlooked either that, by reducing losses, consumption is also reduced. The result is that with greater efficiency it is possible to maintain a more aggressive race pace.
Leonard Kieckebusch, Shell expert on E-Fluids explains: “In Formula E, every watt of power and every second you can gain from increased efficiency matters. This is why Shell develops bespoke fluids for its customers. The powertrain is different from team to team, as well as the transmission coupled to the electric motor. Therefore, teams need different fluids.” To improve efficiency, the parties involved work both on the powertrain and on the fluids, whose chemical composition is customized according to the characteristics of the hardware.
“It is very important that the development of the hardware goes in parallel with that of the lubricants, which must be specific for what they are applied to”comments Kieckebusch. The development of the package is carried out by both parties. Each new specification of E-Fluid is initially tested by Shell and then evaluated by Nissan in bench tests with the entire powertrain. Trials can reach a mileage of 4000 kilometers, the equivalent of two consecutive seasons.
Based on the performance of the Shell-developed E-Fluids, the Nissan team then evaluates how far to go in the design of the Formula E powertrain. At that point, Shell tailors its fluids according to the design characteristics, resulting in continuous refinement. Explains Vincent Gaillardot, technical director of the Nissan team in Formula E: “AND a technical choice to be made at the beginning of the project, as it affects the entire design of the engine. Shell presents us with a range of products with different characteristics. At that point, based on our thermal simulations, we choose the one that we think is the best in terms of efficiency. Essentially, after choosing between Shell’s different options, they know what area we are working on and can move forward with development.”
Direct cooling
The advent of the Gen3 brought with it an increase in horsepower and speeds, requiring the adjustment of the E-Fluids. Meanwhile, new technologies have become available, such as that of direct cooling. The copper windings of the electric motor, heated by the passage of current, are now immersed directly in the cooling fluid, maximizing the surface from which to disperse heat. By increasing the cooling effectiveness, the electric motor can more easily be kept in the temperature window of maximum efficiency.
“With direct cooling, higher cooling capacities are achieved than with indirect cooling. It’s a new technology.” comments Leonard Kieckebusch. “The coolant is in direct contact with the electrical parts. Because of this a dielectric fluid is usedto avoid a short circuit. It is as if you wanted to cool a bottle of wine: you can put it in the fridge, but if you put it in a container with ice, it cools down much faster”.
The arrival of direct cooling has allowed Nissan to design the motor-inverter package differently than in the past, increasing the density of the copper coils to improve efficiency. Explains Vincent Gaillardot: “At some point, you have to choose which technology to use. This is part of the process of optimizing the package around efficiency. Our partner Shell was able to offer us this direct cooling technology. In the initial phase of the project, we defined in which direction the engine could go. The inverter and electric motor are now designed with new technologies”.
The efficiency gain is doubled. In addition to the possibility of designing more efficient geometries, the engine can easily be kept at the correct temperature. In fact, overheating increases power losses from the engine, especially on Gen3 powertrains where the optimum temperature is lower. “We decided to focus on direct cooling also because we knew that the powertrain had to work at lower temperatures. The choice depends on the usage window of the electric motor and the inverter”.
Lubricate efficiently
The Formula E collaboration between the Nissan team and Shell is not just about cooling. Even in the field of lubrication it is possible to find an advantage over the competition, but a job that requires a lot of experimentation, as Kieckebusch explains: “You don’t wake up in the morning knowing exactly which components to put in the lubricant. We experiment with many different chemical compositions, we create a sort of recipe book. Like chefs, we make adjustments to achieve our goals. One of the key parameters of a lubricant is viscosity”.
“The less viscous a fluid is, the less friction you lose. At the same time though, mechanical parts must be protected. If there is not enough viscosity, there is direct contact between the mechanical parts and this can destroy the transmission. Furthermore, by regulation, this cannot be opened for repairs, it must last the whole season, including tests and free practice. Therefore, the lubricant must ensure both efficiency and reliability. They are two contradictory goals. The more viscous a lubricant, the better it helps protect the hardware, but increases friction losses.”
The lubrication process takes advantage of the oil’s ability to interpose itself between the mechanical parts, creating a sort of bearing that prevents the gears from being in direct contact. It’s about a mechanism similar to aquaplaning, when beyond a certain speed the wheels float on the layer of water, losing grip with the asphalt. What is highly dangerous on the road, inside the transmission instead reduces friction and wear. However, all of this occurs only if the oil has enough viscosity and if the rotation speed of the gears is sufficiently high. Since viscosity brings friction, Shell tailors the composition of the lubricant based on the geometries of the powertrain gears and their speeds. For a manufacturer, being able to count on a partner who customizes lubricants exactly on the characteristics of the powertrain is now essential.
In the specific case of Shell, E-Transmission Fluid now boasts up to 70% components of natural origin, reducing the carbon footprint compared to traditional lubricants. It would hardly have been possible to achieve the same result without the great freedom of experimentation afforded by Formula E. Kieckebusch adds: “In the Formula 1 regulations, there are many restrictions on lubricants. In Formula E instead we are free to choose and it’s exhilarating, because we get to try so many different things. In theory, the composition of the fluids could be changed at each race. Like Shell, however, we don’t do it, because we are very attentive to sustainability and even small volumes are important”.
Continuous development
Formula E regulations allow manufacturers to homologate two powertrains in each technical cycle. Therefore, by 2026, the year in which the Gen3 era will end, the Nissan team will be able to update its powertrain. Just like the first version, its characteristics will depend on the new E-Fluids made available by Shell. “Upgrades will also depend on Shell’s progress on both thermal fluid and lubricant. They could offer us new chemical formulas, which at that point we will have to test to verify its benefits. Surely, however, we need to push on development. This is why the collaboration with Shell is so important”. Gaillardot explains.
As was the case for silicon carbide inverters, the skills gained in Formula E on the E-Fluids front are also applicable to products for production cars. Kieckebusch concludes: “Efficiency is a major focus for road cars. One of the reasons that discourages buying an electric car is recharging anxiety. Through our experiments in Formula E we can develop E-Fluids which, by reducing friction and increasing efficiency, can extend the range of road cars. There is so much to learn”.
#Formula #Extra #Power #EFluids #FormulaPassion