Water-based Lubricant (WBL) Innovations for Electric Vehicle

Abstract Electric vehicle (EV) technology has matured over time, improving in some performance areas against traditional internal combustion engine (ICE) vehicles. Despite advancement, there is considerable opportunities for further improvements, particularly in the broader field of lubrication, including areas like grease. As in any mechanical system, greases and lubricants play a significant role in the component life of EV power plants and drivetrains. Moreover, they can significantly contribute to vehicle efficiency, energy savings, and overall driving experience. Since the lubricants in EVs work under harsh thermal and electrical environments, designing an ideal high performance and stable lubricant can be challenging. This paper evaluates the industry's progress on EV lubrication including analyzing existing lithium-based lubricants and spotlighting advanced material additives such as graphene, boron nitride, or cutting-edge ionic liquids. It also discusses optimizing base stock selection, with a focus on Polyalphaolefin (PAO) molecules and designing various additives to enhanc... Read More

Source

Aqueous lubricant composition for hot forging comprising water, graphite, a thickener, and an alkylated diphenyl oxide sulfonate dispersant. The composition maintains 90% or greater graphite dispersion after 30 days, passing a sedimentation test. The dispersant is a molecule with a specific structure, comprising a diphenyl oxide sulfonate group and an alkylated chain.

Source

It is well known that lubricating oils reduce the friction coefficient between two surfaces in contact. Since petroleum lubricants are toxic and have a low biodegradability, they are typically not appropriate for the environment. As a result, as public worries about a pollution-free environment grow, so does the demand for lubricants that are acceptable to the environment. The primary rationale for utilizing vegetable oils in forthcoming bio-lubricant formulations is their high lubricating performance, low toxicity, sustainable, and biodegradability. Plant oils hold great potential as a foundational fluid for bio-lubricants, since their synthetic and vegetable oil-based esters provide the most environmentally friendly option for creating lubricants. In this study, Jatropha and Jojoba raw oil were chemically modified via epoxidation followed by transesterification to produce bio-lubricants. Thus, the aim of this work is to develop a bio-lubricant from jatropha and jojoba methyl ester, further adding nanoparticles multiwalled nanotubes and titanium dioxide for improvement of tribologic... Read More

Source

Electric vehicle transmission fluid formulation designed to meet the unique demands of EV drive systems, providing improved lubrication, wear protection, and compatibility with yellow metals and electrical components. The formulation includes oxidation inhibitors, anti-wear additives, and copper corrosion protection, while maintaining low electrical conductivity and thermal stability. The fluid is engineered to withstand extreme power and torque fluctuations, and is designed to be compatible with a wide range of EV transmission materials.

Source

A lubricating fluid for electric motor systems in hybrid and electric vehicles, comprising a base oil of lubricating viscosity, a high molecular weight succinimide dispersant, an amine salt of a phosphoric acid ester, an ashless dialkyl dithiophosphate, and a sulfur-providing additive. The fluid has a kinematic viscosity of 4.5 cSt or less, 150-250 ppm total phosphorus, and an electrical conductivity of 37 nS/m or less. The succinimide dispersant is derived from a polyisobutylene with a number average molecular weight of 2000 or greater, and is post-treated with a phosphorus and boron containing compound.

Source

Lubricant composition for electric vehicle propulsion systems that improves antiwear and anticorrosion properties by combining triazole corrosion inhibitors with amine- and sulfur-based antiwear additives. The triazole compounds like tolyltriazole prevent corrosion of metal components while the amine-sulfur additives like dimercaptothiadiazoles reduce wear. This combination provides simultaneous wear and corrosion protection for electric vehicle motors, bearings, and transmissions.

Source

A lubricant composition for electric and hybrid vehicle motors, comprising a base oil blend of polyalkylene glycol (PAG), poly-alpha-olefin (PAO), and ester, with an additive package including a sulfur-based extreme pressure agent. The PAG provides thermal stability and low viscosity, while the PAO and ester enhance solubility and compatibility with the extreme pressure agent. The composition is optimized for electric motor applications, avoiding additives typically used in conventional lubricants that can degrade performance.

Source

Electric potential controlled lubrication, also known as triboelectrochemistry or electrotunable tribology, is an emerging field to regulate the friction, wear, and lubrication performance under charge distribution on the solidliquid interfaces through an applied electric potential, allowing to achieve superlubrication. Electric potential controlled lubrication is of great significance for smart tunable lubrication, micro-electro-mechanical systems (MEMS), and key components in high-end mechanical equipment such as gears and bearings, etc. However, there needs to be a more theoretical understanding of the electric potential controlled lubrication between micro- and macro-scale conditions. For example, the synergistic contribution of the adsorption/desorption process and the electrochemical reaction process has not been well understood, and there exists a significant gap between the theoretical research and applications of electric potential controlled lubrication. Here, we provide an overview of this emerging field, from introducing its theoretical background to the advantages and c... Read More

Source

Base oil for automotive transmission and gear systems that provides superior traction and thermal management properties in electric vehicles. The base oil comprises a unique blend of compounds optimized for electric vehicle powertrains, featuring improved oxidation stability, thermal conductivity, and viscosity characteristics. The formulation enables enhanced traction performance in electric vehicles, particularly in the high-temperature regions of the powertrain, while maintaining reliable low-friction operation in the low-temperature conditions of the battery pack and other components.

Source

A lubricating fluid for electric motor systems in hybrid and electric vehicles, comprising a lubricating oil and additives, including a succinimide dispersant, a sulfur-providing additive, and a detergent system, that provides improved wear protection, oxidative stability, and electrical conductivity while maintaining low viscosity. The fluid is formulated with a specific combination of additives that balance antiwear, friction, and corrosion performance while minimizing electrical conductivity.

Source

A lubricating composition for electric and hybrid vehicles, comprising a bio-based oil derived from decarboxylated rosin acid, a base oil, and optional additives. The bio-based oil exhibits improved wear prevention, thermal conductivity, and electrical conductivity properties, while maintaining compatibility with conventional lubricant additives. The composition can be used in various applications, including engine oils, gear oils, hydraulic fluids, and transmission fluids, and demonstrates enhanced performance in electric and hybrid vehicles.

Source

Electric Motors (EMs) containing lubricated bearings must adhere to a variety of operational specifications and related microenvironments.Lubricate products need to perform under these circumstances.The wear and friction of silicon nitride (Si_3 N_4) sliding over toughened chrome steel (52100) were used to measure the tribological effectiveness of three commercially available EM lubricates.The EM lubricates that were examined and comparable viscosity ratings; however, they differed in the proportions of lithium or poly-urea thickener to mineral or synthetic base oil (BO).A variety of surface roughness (SR) levels and temperatures were measured to observe behaviour under various lubrication regimes.The results made possible to compare commercially available solutions directly across a range of application-relevant standards and the analysis techniques created as a foundation for upcoming research on the efficiency of EM lubricate.

Source

Aqueous lubricant composition for mechanical systems comprising water, glycerol, and hypericin, a natural pigment with biological activities. The composition exhibits excellent tribological properties, including wear resistance and friction reduction, making it suitable for lubricating moving parts in mechanical systems, particularly in vehicle propulsion systems.

Source

A transmission fluid composition for hybrid and fully electric vehicles that provides lubrication, cooling, and electrical insulation. The composition comprises a major amount of a lubricating oil basestock and a minor amount of an additive package containing a phosphorus-containing compound, a calcium salicylate detergent, and a non-calcium-salicylate detergent. The additive package enables the fluid to balance competing demands of electrical insulation, wear protection, and low viscosity, while also providing cooling and energy efficiency benefits.

Source

Electric and magnetic fields have been used in various ways to enhance the performance of lubrication systems. The presence of these fields can significantly change the properties of lubricants. The rapid adoption of electric vehicles (EVs) has presented new lubrication-related challenges due to the presence of electric current. There is an urgent need for an in-depth study of lubrication systems subjected to such fields. This paper highlights recent research works on several key areas of lubrication involving electric or magnetic fields, which are:1) electric double layer in lubrication, 2) electrorheological fluids, 3) magnetorheological fluids, 4) ferrofluids, and 5) typical fluids used in the current EVs and typical surface failures of bearing components in EVs. Commonly used lubricants in each area are reviewed; lubrication mechanisms and related mathematical models are summarized; methods for and results from numerical analyses and experimental explorations are discussed; and common features of lubrications in different fields are explored. Based on the current research progres... Read More

Source

Electric vehicles (EVs) have gained increased attention in recent years owing to their excellent performance and emission of less hazardous products to the surroundings. The varied design of EVs compared to the internal combustion engine vehicles has created new requirements in lubricants and fluids for their operation. The increasing electrification of vehicle drivetrains has led to lubricants being in contact with more electrical components, such as motors, sensors, battery modules, and power electronics. This has led to different operating conditions, such as being subjected to an electric field, higher rpm, and higher thermal stress, affecting the electrical properties of lubricants, especially for electrified transmission fluid. The electrical properties of lubricants play a vital role in preventing corona discharge and arc absorbance, which can cause premature failure and electromagnetic interference problems in motors, leading to bearing instability, excessive vibrations, and noise. Understanding the interactions of lubricants with the electric field is crucial for optimizing ... Read More

Source

To increase the driving range of electric vehicles (EVs) and to make them less dependent on fossil-based technology, it is important to switch to new types of lubricants with low friction and renewable origin. During the past couple of decades, researchers found that glycerol, which is biodegradable and nontoxic, can provide superlubricity even under high contact pressure with rough surfaces. Glycerol can also be used as a coolant for EVs to increase the efficiency of the electric motors. This chapter gives a summary of the tribological performance of different contacts, i.e., steel-steel, steel-diamond-like carbon (DLC), DLC-DLC, steel-self-lubricating materials, and steel-ceramic, which are lubricated by glycerol.

Source

Friction and lubrication are ubiquitous in all kinds of movements and play a vital role in the smooth operation of production machinery. Water is indispensable both in the lubrication systems of natural organisms and in hydration lubrication systems. There exists a high degree of similarity between these systems, which has driven the development of hydration lubrication from biomimetic to artificial manufacturing. In particular, significant advancements have been made in the understanding of the mechanisms of hydration lubrication over the past 30 years. This enhanced understanding has further stimulated the exploration of biomimetic inspiration from natural hydration lubrication systems, to develop novel artificial hydration lubrication systems that are cost-effective, easily transportable, and possess excellent capability. This review summarizes the recent experimental and theoretical advances in the understanding of hydration-lubrication processes. The entire paper is divided into three parts. Firstly, surface interactions relevant to hydration lubrication are discussed, encompass... Read More

Source

The understanding of the lubrication properties under electrical conditions, in order to achieve the suppression of electrical damage and even use the electrical environment to promote lubrication, is highly relevant to the bearings used in electric cars. In this chapter, important research progress on lubrication as well as the premature failure of bearings under electrical conditions in the past decades will be briefly reviewed. The basic research on dry friction under electrical conditions and then the molecular adsorption and orientation at the lubricated interface under electrical conditions will be discussed. Subsequently, microbubble behaviors in thin lubrication films under electrical conditions will be introduced. The electrodamage in bearings under electrical conditions and the protection technology are discussed in the final part.

Source

Extending the driving range of battery-based electric vehicles is one of the many challenges that need to be overcome before mass adaptation by the public. One of the ways to improve the driving range is to make the power unit more efficient. Currently, ultralow viscosity lubricant is used in power units. The fluid was developed for automatic transmissions and, therefore, not optimized for power unit applications. Before developing an optimized fluid, it is critical to understand the lubrication regimes in power units and quantify the amount of boundary, mixed, and hydrodynamic regimes. Once the relative proportions of boundary, mixed, and hydrodynamic regimes are known, lubricant formulators can select appropriate additive components for the reduction of power losses in those regimes while maintaining component durability (mechanical wear, corrosion, material compatibility, etc.) and lubricant life (oxidation). Understanding the lubrication regimes required an evaluation of power unit efficiency using a production unit under a broad range of speeds and torques. The efficiency data w... Read More

Source