A Study on the Performance of Lubricating Greases for Electric and Hybrid Vehicle Applications

The automotive sector has always been closely connected with the lubricants industry, with the latter continuously developing new technologies, specs and products in order to address the evolution in this segment. Electrification represents a significant change in the major powertrains and, thus, it will inevitably affect the selection, development and market share of several types of lubricants, such as lubricating greases. The evolution of the EV/HV segment will increase the demand and the importance of lubricating greases for electric motors. New challenges for grease formulation may arise from the neighboring electric currents and electromagnetic fields and higher energy efficiency requirements. In this paper, the perspectives and the projected evolution of automotive e-mobility is reported and the subsequent influence on the main grease performance requirements are analyzed. Moreover, the alteration in the applications are examined. A series of lubricating grease formulations are prepared, based on polyurea thickener type without additives, and a number of technical properties and parameters are determined in order to evaluate their performance with regards to current requirements and future development trends for greases intended for lubrication in vehicles with electric and/or hybrid powertrains.