In a development that may revolutionise lubrication for electric vehicles (EVs), TotalEnergies has revealed that it has overcome the technical challenges to develop a water-based lubricant (WBL) suitable for direct-cooling electric motors.
WBLs are not new in themselves. TotalEnergies has been selling its Total Folia metalworking for years, with operators benefitting from excellent levels of lubricity and cooling. WBLs have previously not been believed to be a realistic prospect for electric motors, however, because the fluid needs to directly contact components where the electric voltage and current may be high while also needing to provide lubrication, an oil-based lubricant easily satisfies both these essential properties.
Nevertheless, water has some attractive properties compared to oil. Its viscosity is lower, it has twice the heat capacity and its thermal conductivity is four times higher. TotalEnergies therefore set out to find a chemical formulation based on water that could achieve all the desirable properties. The company then tested its WBL against a reference oil-based lubricant and monitored the temperatures of different elements of an e-motor. It found the WBL achieved greater cooling for all components, with the temperature reductions varying from 16% for the windings to 58% for the shaft. It is also expected to have a lower overall environmental impact.
While the new technology promises to revolutionise EV cooling in future, you can benefit from TotalEnergies’ lubrication expertise with their current products. At TrAchem, we can supply products like the Total Multis grease and Total Carter gear oil, so drop us a line to learn more.