Dr. Martin Webster
Senior Research Associate, Lubricants Technology
ExxonMobil Research and Engineering
Lubrication and Tribology Trends and Challenges in Electric Vehicles
Recent studies such as STLE's Emerging Trends reports confirm the adoption of electric vehicle (EV) technology is increasing and now represents one of the fastest growing passenger vehicle segments. This will have a significant impact on future vehicle fluid requirements, component design and overall vehicle architecture. While at first glance the use of familiar mechanical components might suggest otherwise, EVs will pose some interesting tribological and fluid technology challenges.
This presentation will cover the key drivers behind the vehicle electrification revolution. It will explain why electrification is an increasingly attractive route toward meeting current and projected future emission goals. A brief review of the major components that make up a battery electric vehicle (BEV) will be presented. The operating characteristics of electric motors impacts the design of the gearbox and driveline components. In turn, this impacts future lubrication requirements and introduces some significant opportunities for innovation. In particular, the need to balance supporting high torque loads at low speed versus lubrication at very high motor speeds represents a difficult compromise between antagonistic lubrication requirements.
Thermal management and cooling has emerged as one of the key fluid requirements in EVs. Multiple components such as batteries, motors and electronics have unique thermal management requirements. Currently there is a diversity of approaches being used to achieve effective thermal management, placing different demands on the fluids. One option of combining cooling and lubrication into a single system using the same fluid offers advantageous simplifications. However, the resulting fluid would need to meet a very demanding series of new performance requirements.
Finally, we will highlight the need for the pro-active participation of the tribology community in developing this rapidly developing technology. Previous experience in other areas has shown that tribology can play a key enabling role in early identification of critical challenges and finding appropriate solutions. STLE is responding to this challenge by providing featured content in its publications and a forum for idea exchange.
Martin Webster currently holds the position of senior research associate and program leader at ExxonMobil’s Corporate Strategic Research laboratory in Annandale, New Jersey. He is responsible for a number of the longer range lubrication and tribology research programs. Webster gained his Ph.D. in tribology from Imperial College London, where his work on rough surface contact mechanics resulted in being awarded the Institute of Mechanical Engineers Tribology Bronze Medal in 1986. Following a postdoctoral assignment with Shell Research in the UK, he spent 2 years working on the design and analysis of wind turbine systems with the UKbased Wind Energy Group (WEG). He has since accumulated more than 20 years of experience working with ExxonMobil in both research and product development positions. His research focus has been on the fundamentals of lubricated contacts, including the measurement and characterization of elastohydrodynamic lubrication (EHL) performance, modeling EHL contacts, rolling contact fatigue phenomenon, and the interactions of lubricant components with engineering surfaces. He has published numerous papers and patents in each of these areas. He has been active in various societies and technical committees, including the Gear Research Institute, the ASME Rolling Element Bearing Committee, and the STLE Gears and Gear Lubrication technical committee. In 2006 he was elected to join the STLE Board of Directors which culminated in serving as the STLE President 2015-16.