Transmission Fluid Additive Package for EV Wear and Insulation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Formulating a transmission fluid that meets the competing demands of providing electrical insulation, wear protection, and low viscosity for hybrid and fully electric vehicle transmissions is challenging, as existing solutions often compromise on one or more of these properties.
Innovation Solution
A transmission fluid composition comprising a major amount of lubricating oil basestock, specific additives including a mixture of compounds of structures (I) and (II), a detergent comprising calcium salicylate, and a basic nitrogen-containing ashless dispersant, which collectively provide high volume resistivity and wear protection while maintaining low viscosity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If the viscosity of transmission fluid is reduced to lower drag and friction, then energy efficiency is improved, but wear protection capability deteriorates
Solution Approach 1:
The patent modifies the chemical composition parameters of the transmission fluid by incorporating specific additives (dithioester compound, organometallic compound, and nitrogen-containing compound) in optimized ratios. This allows the fluid to maintain low viscosity for reduced drag while the additives provide enhanced wear protection through chemical film formation on metal surfaces, resolving the contradiction between low viscosity and wear protection.
Solution Approach 2:
The patent creates a composite lubricant formulation by combining multiple functional components: a base oil with specific viscosity characteristics, dithioester compounds for boundary lubrication, organometallic compounds for extreme pressure protection, and nitrogen-containing compounds for corrosion inhibition. This composite approach allows the fluid to simultaneously achieve low viscosity for energy efficiency and comprehensive wear protection through the synergistic effects of different additives.
2Reliability
If conventional additive combinations are used in transmission fluid, then wear protection is provided, but volume resistivity becomes too low for electrical insulation requirements
Solution Approach 1:
The patent carefully selects and optimizes the chemical parameters of the additive package, specifically choosing compounds with low ash content and controlled polarity. The dithioester and organometallic compounds are selected in specific ratios that provide adequate wear protection while minimizing ionic content that would reduce volume resistivity. This parameter optimization allows the fluid to meet both wear protection and electrical insulation requirements.
Solution Approach 2:
The patent uses small concentrations of highly effective additive compounds that provide sufficient wear protection without creating long-term deposits or sludge. These compounds are designed to be consumed or depleted over time, preventing accumulation that would degrade electrical properties. The additive package is formulated to maintain effective concentrations for wear protection while avoiding excessive buildup that would reduce volume resistivity.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The composition achieves enhanced wear protection and volume resistivity, particularly in lower viscosity formulations, thereby effectively addressing the demanding requirements of hybrid and fully electric vehicle transmissions.
Implementation Method 1
the transmission fluid must also provide electrical insulation (or sufficiently high volume resistivity)
Implementation Method 2
The mechanical parts, gears etc., must be adequately protected from wear and corrosion just as in any conventional transmission
Implementation Method 3
the transmission fluid must also provide electrical insulation (or sufficiently high volume resistivity), good compatibility with metals present in electromechanical components (commonly copper), and good cooling ability
Data Source
AI summary
A transmission fluid composition contains a major amount of a lubricating oil basestock, and a minor amount of an additive package comprising: (i) a mixture comprising two or more phosphites and/or phosphates; (ii) one or more thioester compounds; (iii) a detergent comprising calcium salicylate; and (iv) a poly(alkylene amine)-based ashless dispersant endcapped with metallocene-catalyzed PAO arms. Such a transmission fluid may be used for controlling/reducing wear in at least partially electrically-powered transmissions and/or for cooling/insulating electrical/electronic components of at least partially electrically-powered drivetrains.