Enabling Fast Discharge Li-Ion Batteries Via Electrolyte Formulations for Urban Air Mobility Applications

Abstract

High-power discharge requirements are critical for lithium-ion batteries (LIBs) used in electric Vertical Takeoff and Landing (eVTOL) vehicles that are increasingly considered in urban mobility. This investigation places a particular emphasis on understanding the impact of electrolytes on discharge processes and rate capability. We aim to compare the discharge behavior of LiBs using a conventional electrolyte (Gen 2: 1.2 M LiPF6 in EC:EMC) and the dual salt LiTFSI-LiBOB-based electrolyte. We carefully examine the profiles of charging and discharging, the behavior during extended cycles, impedance spectroscopy results, and the characteristics of the electrode surface. Our research findings demonstrate the complex relationship between the composition of electrolytes and the specific high-power discharge requirements of electric vertical takeoff and landing (eVTOL) systems. This research highlights the importance of customizing electrolyte compositions to optimize energy storage density while simultaneously enabling higher power extraction to enhance performance in short-range electric aviation.

Keywords: Urban air mobility, Lithium-ion batteries, Fast discharge, Rate capability, eVTOL, Electrolyte formulations