PRODUCTS & SERVICES | AFTON
High-efficiency, low-risk electrified transmission fluid Afton shares independent research into efficiency gains and highlights the advantages of applying fluid expertise during eAxle development The right electrified transmission fluid (ETF) can deliver significant efficiency gains of up to 1.5% without impacting durability, using optimized formulation based on tailored additive technology with a base oil. SwARC, a joint venture between China Automotive Technology & Research Center and US-based Southwest Research Institute, has progressed ETF testing with the most common eAxles, comparing the performance of 11 candidate fluids from different suppliers. Four different OEM platforms were tested through four eAxle efficiency test procedures, at up to three different coolant temperatures, using the factory fill fluid as the reference oil. The four efficiency procedures were CLTC (China Light Vehicle Test Cycle), used to measure passenger EV energy consumption and driving range for certification in China, steady state testing, the typical working conditions test to assess different driving scenarios, and rapid acceleration (0-100 km/h) to examine efficiency under more extreme conditions. The rapid acceleration test is designed to mimic the impact of frequent start-stop driving on power performance. Owing to its tailored additive technology, carefully balanced viscometrics, and enhanced traction performance, the Afton candidate fluid delivered the most significant efficiency increases across all test procedures and eAxle platforms. In the CLTC test conducted with the coolant at 200C,
Figure 1: SwARC CLTC 2023: Afton fluid technology delivers 1.5% efficiency gain
Afton’s fluid technology increased eAxle efficiency by 1.5% over the reference oil, which will translate to longer driving distances over spring, autumn and even winter, especially useful for EVs which face range challenges in cooler climates. Electric oil pump power usage was also measured during testing, and Afton’s candidate fluid enabled the pump to work at 40% less
current than the reference fluid. Although pump operation is not a main influencing factor in overall eAxle efficiency, using an advanced fluid can help reduce oil pump size and cost. Viscosity, cooling and traction are the three inter-related lubricant levers that influence eAxle efficiency,and balancing them in a high-efficiency ETF is a complex
Figure 2: SwARC CLTC 2023: Afton fluid technology reduces EOP power draw by 40%
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process. Simply using the lowest viscosity fluids has the potential to reduce mechanical protection and increase compatibility issues with seal and insulation materials. Finished fluids must also accommodate divergent OEM approaches to eAxle design through additive componentry, varying molecular structures, and degree of uniformity of different base oils. Afton’s approach brings together its additive expertise with insights from modeling and simulation to create a low-viscosity fluid with low traction properties. This SwARC research demonstrates the clear role high-efficiency ETF can play in helping OEMs to meet increasing power density targets without compromising mechanical protection, compatibility, or durability. www.aftonchemical.com