Haghkhah Hasty, Ghalami Choobar Behnam, Amjad-Iranagh Sepideh
Department of Chemical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran.
J Mol Model. 2020 Aug 1;26(8):220. doi: 10.1007/s00894-020-04464-8.
In this work, a computational framework is proposed by utilizing molecular dynamics simulation to explore the existing relation between molecular structure and ionic conductivity of the electrolyte system [LiPF+(EC+DMC 1:1)] consisting of a mixture of cyclic ethylene carbonate (EC) and acyclic dimethyl carbonate (DMC) solvents and lithium hexafluorophosphate (LiPF) salt to propose as a novel mixed organic solvent-based electrolytes to promote the performance of lithium-ion batteries (LIBs). To acquire a clear understanding of the structural and transport properties of the designed electrolytes, quantum chemistry (QC) calculations and molecular dynamics (MD) simulation are used. In the first step, the accurate molecular structures of the studied electrolytes in addition to their corresponding atomic partial charges are evaluated. The MD simulations are performed at 330 K varying the LiPF concentration (0.5 M to 2.2 M). Analysis of the obtained results indicated that ionic diffusivity and conductivity of the electrolytes are dependent on the structure of solvated ions and lithium salt (LiPF) concentration. It is found that the obtained MD simulation results are in reasonable agreement with experimental results. Graphical abstract A representation of dependence of transport properties of electrolyte system [LiPF6 +(EC+DMC 1:1)] as function of salt concentration to be used in Lithium-ion batteries (LIBs).
在这项工作中,通过利用分子动力学模拟提出了一个计算框架,以探索由环状碳酸亚乙酯(EC)和无环碳酸二甲酯(DMC)溶剂以及六氟磷酸锂(LiPF)盐组成的电解质体系[LiPF+(EC+DMC 1:1)]的分子结构与离子电导率之间的现有关系,从而提出一种新型的基于混合有机溶剂的电解质,以提升锂离子电池(LIBs)的性能。为了清晰了解所设计电解质的结构和传输性质,使用了量子化学(QC)计算和分子动力学(MD)模拟。第一步,除了研究电解质的相应原子部分电荷外,还评估了其精确的分子结构。MD模拟在330 K下进行,改变LiPF浓度(0.5 M至2.2 M)。对所得结果的分析表明,电解质的离子扩散率和电导率取决于溶剂化离子的结构和锂盐(LiPF)浓度。发现所得的MD模拟结果与实验结果合理吻合。图形摘要 电解质体系[LiPF6 +(EC+DMC 1:1)]的传输性质随盐浓度变化的关系图,用于锂离子电池(LIBs)。