One benefit of electric vehicles (EV) is fewer moving parts. That means the need for lubricants is reduced, but not eliminated. EVs still require a level of lubrication, including for gear reducers and engine and battery cooling.
Early electric vehicles – both cars and trucks – have used traditional lubricants to get the job done. But, according to Selda Gunsel, vice president of technology for Shell Lubricants, the old standbys are not up to the task.
“Electric vehicles, whether they are passenger or commercial vehicle, do not use engine oil,” she told FreightWaves. “But these vehicles still have transmissions systems, so they need transmission fluid. When you look at an electric vehicle, the transmissions systems are very different than a combustion transmission system. The fluid needs to act as a coolant and it needs to be compatible with the high-voltage electrical components.”
In 2019, Shell launched E-Fluids – specialized fluids designed to protect components of battery electric and fuel-cell electric automobiles. It has now expanded that line to include commercial trucks and vans.
Gunsel said as more electric vehicles reach roadways in the years ahead, it’s important to have lubricants that offer low conductivity and are compatible with copper – a common material in electric vehicles.
“We feel if you can develop specialized fluids that have good material compatibility … with higher oxidation stability, you can improve the performance and efficiency of the system,” she said. “You never really worry about electrical components [in combustion engines]. Greases are needed to lubricate bearings, e-motor bearings, etc. These greases need to operate in high-voltage environments and electrical charges cause a breakdown of the grease material. So specially formulated greases need to be [available].”
Morgan Stanley is predicting that EV production will surpass combustion engine auto production by 2035, so specialized lubricants will play a key role in optimizing vehicle performance, Gunsel said.
On the commercial vehicle side, a report by Allied Market Research predicted the global electric truck market would grow from $422.5 million in 2019 to $1.89 billion by 2027. Asia currently dominates the electric truck market, but North America and Europe are expected to grow quickly.
California is requiring 75% of Class 8 trucks sold in the state by 2035 to be electric. Most major truck makers are currently working on electric truck projects – either battery-electric or hydrogen-electric – and they are being backed by major fleets.
“Schneider’s commitment to innovation is matched only by our commitment to operating sustainably,” Jake VandeLoo, vice president of equipment engineering at Schneider, said in an August statement announcing Schneider National’s (NYSE: SNDR) participation in a test of Daimler Trucks North America’s eCascadia. “Joining the Freightliner CX Fleet is a great opportunity to flex both of those muscles and help lead the industry in transitioning to more sustainable transportation options.”
Volvo is involved in the California LIGHTS program with the California Air Resources Board (CARB) along with 13 other entities to develop a blueprint for electric truck deployment.
As more commercial electric trucks are developed, the need to expand the E-Fluid portfolio was obvious to Shell.
“Manufacturers were relying on fluids developed for internal combustion engines, so they weren’t optimized for best performance and efficiency,” Gunsel said. “Traditional fluids can be used, [but] especially when it comes to commercial vehicles, reliability, durability and cost of ownership are critical factors. You want to make sure you don’t have downtime.”
Shell has been involved in a hydrogen-electric truck project in California involving Toyota and Kenworth, but Gunsel said the company is working with all the hardware manufacturers because, unfortunately, there is no industry standard as yet for fluids for electric vehicles.
“We are working very closely with the OEMs to core engineer the fluid because every OEM is using different materials and the transmission speed can impact the performance,” Gunsel said.
The Shell E-Fluids line, which is based on Shell’s gas-to-liquid technology, includes e-transmission fluids, e-greases and battery thermal fluids. According to the company, the E-Fluids offer longer lifetime lubrication, eight times lower electric conductivity when cooling the electric motor under typical operating conditions compared to conventional transmission fluids and, when compared to a competitive e-mobility fluid, three times less copper erosion and 9% higher thermal conductivity.
Gunsel said Shell is working to perfect its “emergent cooling” process, which would allow electric vehicle batteries to be dropped directly into an E-Fluid, thereby cooling the battery more effectively.
Gunsel expects the E-Fluids line to expand with products designed for specific vehicles and applications. Here, Shell’s global scale will help it, she said, and the use of the gas-to-liquid technology provides an added benefit.
“Gas-to-liquid technology allows us to start with natural gas and convert it to hydrocarbons,” Gunsel explained. “Starting with natural gas and converting it into long-chain hydrocarbons … allows us to develop a very clear lubricant base oil. We start with a base oil that has the right properties that enable higher efficiency in powertrains, and … depending on the design of the transmission and materials, we work with different additives to tailor the lubricant for the system.”
In 20 years, three-quarters of commercial vehicles sold in California and elsewhere could be electric. The development of fluids specifically for these vehicles could boost their performance and improve vehicle life, a critical measurement for commercial operators.
Shell’s E-Fluids are available now.