Mar 31, 2020
Posted by Tom Curtis, President, Lubrizol Additives
The electrified drivetrain brings with it a new set of formulation challenges for lubricants and fluids, and there are two major questions formulators need to grapple with under this continued evolution.
The first: Do we properly understand the challenges posed by electrification and the performance required to meet those challenges?
The second: Do we have the right tools to develop that next generation of fluids?
Answering the first question involves thinking beyond the engine when it comes to the importance of lubes and fluids. Sometimes it seems like the engine may get all the credit, but electrification places increased importance on all systems, specifically transmission technology. Consider that hybridized vehicles combine the performance of an electric motor and an internal combustion engine (ICE) to provide more efficient transportation—and the transmission is where it all comes together.
There’s a lot of work currently happening in the driveline space to determine the best transmission technology for both hybrid vehicles and battery-electric vehicles. As of yet, no one has settled on one answer, and the situation is creating some interesting challenges from the fluid perspective. Certain new transmission designs utilize conventional fluids, but additional work is revealing that as this hardware becomes further refined, more optimized fluids will be required.
For example: Many conventional ICEs operate somewhere between 2–3,000 rpm under regular cruising operation. Rev the engine, and you’ll hit between 5–6,000 rpm under some driving conditions. Under those same driving conditions, electric motors spin somewhere between 10–15,000 rpm. Some concepts have electric motors running at upward of 30,000 rpm.
That is a dramatic difference—and accounting for that difference falls to the transmission. Which ways are best to translate such high rpm to an axle and wheels on the road? There are many considerations to be made here, including the impact significantly higher rpm will have on a transmission fluid. First, high speeds can cause conventional fluids to become foamy and frothy. This compromises thermal properties, leading to temperature—and therefore operational—issues of the transmission. Thus, anti-foaming agents and heightened thermal stability are increasingly important in evolving transmissions fluids.
That leads to our second question: Do formulators have the right tools to develop such solutions?
As regulatory bodies around the world seek to curb emissions and the use of potentially harmful or toxic substances, chemistry that formulators have long relied upon for their performance characteristics have come under question. Europe’s Registration, Evaluation, Authorization and Restriction of Chemicals (REACH) program is one of the most notable examples, which came into effect in 2007 to regulate, evaluate, authorize and restrict chemicals based on their intrinsic properties; per the European Union: “One of the main reasons for developing and adopting the REACH Regulation was that a large number of substances have been manufactured and placed on the market in Europe for many years, sometimes in very high amounts, and yet there is insufficient information on the hazards that they pose to human health and the environment. There is a need to fill these information gaps to ensure that industry is able to assess hazards and risks of the substances, and to identify and implement the risk management measures to protect humans and the environment.”
It's good progress as our global society seeks to become more sustainable—but it also means that workhorse chemistries that have been in use for decades are now in need of replacement. It’s a formulators’ job to find and identify an effective replacement chemistry.
Engines and transmissions will only continue to evolve in the coming years and, in the near term, the ways in which that happens will be increasingly diverse. Meanwhile, regulation of potentially harmful chemistries will continue to grow stricter. It’s a pressing, important challenge for formulators around the world.
New chemistry solutions for an evolving automotive industry are a necessity to enable tomorrow’s technology, and it will require ongoing, continuous investment to make it happen.
At Lubrizol, we’re making that investment. Our teams are continuously working on new chemical technology and innovative formulations. We put those formulations through rigorous testing, and we work hard to bring reliable solutions to market. The evolution of automotive technology and a more sustainable future depend on it.