Boron-containing fullerene-based salts with cyclic carbonate solvents as electrolytes for Li-ion batteries and beyond

Abstract

Replacement of carbon atoms by a heteroatom in fullerene is a promising route that enhances the electronic properties of fullerenes and results in hetero fullerene-based effective agents ensuring applications in vivid fields of the solar cell, cathode materials for batteries, etc. Towards the development of new electrolyte salts, attention has been paid to facilitating ion mobility in particular and moderate stability of the anions in addition. From the atomistic molecular dynamics simulation studies, for the first time, we uncover that the boron-containing hetero fullerene, C₅₉B⁻ anion-based LiC₅₉B, and NaC₅₉B salts in cyclic carbonate solvents can act as efficient electrolytes by improving the transport phenomenon of the metal ions in solution, importantly for Li⁺ and satisfactorily for Na⁺ as compared to their commonly used BF₄⁻ anion based salts. Additionally, our study revealed that apart from LiC₅₉B, and NaC₅₉B salts, C₅₈B₂²⁻ based MgC₅₈B₂ salt can facilitate the ionic conductivity of the electrolyte. The properties of the proposed electrolyte under an electric field and different temperatures were investigated. Some of the bulk properties of the used electrolytes to some extent were found to be improved in the presence of these salts. The first principle-based electrochemical calculations further justify the stability of the proposed anions. The initial investigation from the Reactive force-field (ReaxFF) based atomistic simulations study elucidates that LiC₅₉B reduces the decomposition of the EC solvent compared to LiBF₄ and facilitates solvent stability.