LiTFSI Solvation and Transport Properties in Mixed Electrolytes: Impact of Boron‐Based Additives From Computer Simulation

ABSTRACT Extensive molecular dynamics simulations were performed to investigate the structure, solvation, and transport behavior of LiTFSI in solvents; 1,3‐dioxolane (DIO) and dimethyl‐sulfoxide (DMS) in pure form and their binary mixtures with ethylene carbonate (EC) in the presence/absence of boron‐based additives, BC 2 HBNS(NO 2 ) 2 3 (CBSt) and boronic acid (BOH). In DIO‐based electrolytes, although significant ion pairing is observed between Li⁺ and TFSI − , introduction of EC weakens these interactions, and further addition of CBSt disrupts Li⁺–TFSI − coordination, indicating enhanced ion dissociation. Li⁺ shows well‐defined solvation shells dominated by DIO, with EC playing a secondary role. In contrast, DMS‐based electrolytes inherently exhibit weaker Li⁺–TFSI − interactions, characterized by broader g(r) peaks, which promotes ion mobility. CBSt again mitigates the ion pairing effect. Interaction energy analysis confirms that Li⁺–TFSI − pairing is strongest in pure DIO and weakest in DMS, with the inclusion of CBSt decreasing the interaction energy effectively. A similar trend in the solvation of Li + was observed for DMS‐based electrolytes. Interestingly, while DIO‐based electrolytes were less effective in reducing ion‐pair formation, the cation transport numbers were significantly good. In contrast, DMS‐based electrolytes, in the presence of boron‐based additives, improve cation transport and effectively decrease ion pairing, especially in the presence of EC and/or CBSt in the solution.