Study of In-Plane and Interlayer Interactions During Aluminum Fluoride Intercalation in Graphite: Implications for the Development of Rechargeable Batteries

Abstract

The electrolyte intercalation mechanism facilitates the insertion and extraction of charge into the electrode material in rechargeable batteries. Aluminum fluoride (AlF3) has been used as an electrolyte in rechargeable aluminum batteries with graphite electrodes, demonstrating improved reversibility of battery charging and discharging processes; however, the intercalation mechanism of this neutral molecule in graphite is so far unknown. In this work, we combine scanning tunneling microscopy (STM) in ultrahigh vacuum conditions, calculations based on density functional theory, and large-scale molecular dynamics simulations to reveal the mechanism of AlF3 intercalation in highly oriented pyrolytic graphite (HOPG). We report the formation of AlF3 molecule clusters between graphite layers and their self-assembly by graphene buckling-mediated interactions and explain the origin and distribution of superficial blisters in the material. Our findings have implications for understanding the relationship between the mobility and clustering of molecules and the expansion of the anode material. This, in turn, paves the way for future enhancements in the performance of energy storage systems.

Optimization of Lithium Metal Anode Performance: Investigating the Interfacial Dynamics and Reductive Mechanism of Asymmetric Sulfonylimide Salts

“…The asymmetric structure of LiDFTFSI and the high reactivity of the -CF2H group rapidly dissociate to form AlF3, which then protects the anode. This protective layer helps in passivating the Al 0 current collector, which is crucial for the battery's stability and longevity [61].…”

Functionalized Non-Glass Fiber Nanoporous Separator for High-Performance Aqueous Zinc Ion Batteries

“…However, conventional nonrenewable energy sources, including various fossil fuels, crude oil, and raw coal, are depleting rapidly, exacerbating the issue of energy scarcity. − This concern is further compounded by the environmental pollution resulting from fossil fuel usage, adversely affecting human health and the Earth’s ecological balance. The pressing need to address growing energy demand and escalating environmental pollution has propelled the development of renewable energy technologies. − Key to the transition to green energy and carbon neutrality is large-scale energy storage technology, which has become a focal point of research and development. − The current prominence of mature lithium-ion batteries, with their high operating voltage, impressive theoretical capacity and energy density, and excellent electrochemical performance, has led to widespread use in electric vehicles, electric bicycles, and various other applications. − However, lithium-ion batteries still present noteworthy drawbacks, including potential safety issues arising from the leakage of toxic organic electrolytes and the high cost associated with the scarcity of lithium resources. − In light of these challenges, there is an urgent need to explore the next generation of energy storage systems that prioritize high safety and low cost . Such advancements will represent a significant stride toward the future of energy storage.…”