Researchers at Argonne National Laboratory have proposed a new fluoride-based solvent that maintains a robust protective layer for hundreds of cycles in lithium metal anode batteries.

One of the contenders as an anode to the current graphite and graphite-silicon formulation in current lithium-ion battery technologies is lithium metal. However, while the lithium metal anode battery has the potential to more than double the energy density of a lithium-ion battery, the battery capacity is rapidly eroded within less than a hundred charge-discharge cycles using conventional electrolytes. The research team at ANL substituted a fluorine solvent into the electrolyte that has maintained higher battery performance in lithium metal anode batteries over several hundred cycles in a test cell.

Fluorine is already gaining rapid exposure in the lithium-ion battery narrative. The electrolyte solution in Li-ion batteries is typically based on fluorine-containing lithium salts. In addition, hydrofluoric acid (HF) is used in the chemical processing of natural graphite to enable the production of spherical graphite for use in Li-ion battery anodes. This compounded demand growth has already resulted in a staggering growth forecast for acidspar – the main raw material for producing fluorine chemicals.

Project Blue forecasts acidspar market to double by 2037. There is increasingly less downside in fluorine demand, if the element and its compounds remain key ingredients in unlocking improved performance of current battery technologies, such as cold-climate driving (read more here), and also accelerate competing battery technologies. OEMs are already acutely aware of the exposure to rapid-growth and China-dominated fluorine market and several projects are already in place in Europe and the USA to start diversification of this critical material for electric vehicle supply chains.