The Fluorine Toolbox: from Molecular Design to Advanced Batteries

The increasing demand for high-performance rechargeable batteries, particularly in energy storage applications such as electric vehicles, has driven the development of advanced battery technologies with improved energy density, safety, and cycling stability. In this regard, fluorine has emerged as a crucial element in achieving these goals with fluorinated materials being employed in a wide range of battery applications, including solid and liquid electrolytes, electrolyte additives, solvents, binders, and protective layers for electrodes. This review explores the design and utilization of fluorine-containing materials in advanced batteries, focusing on the significance of controlling their chemical structure and understanding their impact on battery performance. A key aspect is the role of fluorinated materials in facilitating the formation of a thin, protective film of corrosion products at the metal-electrolyte interface, which serves as a barrier against further chemical reactions with the electrolyte. The electron-withdrawing property of fluorine endows these fluorinated materials with high oxidative stability at high voltages. Moreover, the non-flammable nature of fluorinated compounds contributes to the design of batteries with enhanced safety and prolonged lifespan. Additionally, we discuss the current challenges and future directions in harnessing the battery-related aspects of fluorinated materials, with a focus on the regulatory landscape surrounding the use of fluorinated compounds.