Identifying the best carbonate electrolyte solvents for Calcium-ion batteries using computational approaches

Rechargeable lithium-ion batteries (LIBs) are the predominant commercial power sources for mobile phones, laptop computers, portable electronics, electric vehicles, and miscellaneous power devices due to their high energy density, good rechargeability, and long cycle life [۱]. However, concerns surrounding future Li availability, cost, and safety have prompted the search for competitive alternatives to rechargeable LIBs [۲]. Recently, rechargeable batteries based on multivalent ions (Ca۲+, Mg۲+, Al۳+) have garnered significant attention as candidates for replacing Li-ion batteries due to their higher energy density [۳]. This parameter is particularly important as batteries are increasingly used in transportation and the size and mass of the unit can be a limiting factor. Calcium-ion batteries are proposed as particularly promising systems due to their low cost, high natural abundance, easy access, and low reduction potential [۴].In this computational study, we aim to provide theoretical insight to predict the best chemical structure of the carbonate electrolytes using combined molecular dynamics calculations and electronic structure calculations. Moreover, we have investigated the solvation behavior of calcium tetrafluoroborate in both neat carbonates and carbonate mixtures using combined molecular dynamics simulations and quantum mechanical calculations. Our results indicate that both neat ethyl methyl carbonate and a mixture of ethylene carbonate and diethyl carbonate show the highest free energy of solvation for the Ca۲+ ion, making them likely candidates for further focus. This observation should assist in the rational design of next-generation battery materials in the rational selection of additives, counterions, or electrolyte solvents.

کلیدواژه ها:

Calcium Ion Batteries ، Molecular Dynamics ، DFT ، Calcium Tetrafluoroborate.