摘要
The anion storage behavior of graphite positive electrode in a dual-ion battery is closely related to the solvation of anion in the corresponding electrolyte solution.The classical electrolyte solutions of Li BF_(4)^(-)sulfolane(SL)have long been recognized in the community of lithium batteries and still appear promising in dual-ion batteries.Nevertheless,the solvation of BF_(4)^(-)by SL has seldom been addressed before.In this study,the solvation states of SL-BF_(4)^(-)are adjusted by varying LiBF_(4)concentration or introducing auxiliary salts of LiPF_6or SBPBF_(4)(SBP:spiro-(1,1')-bipyrrolidinium)in the electrolyte solutions of Li/graphite dualion cells.The electrochemical storage processes of SL-BF_(4)^(-)anions in graphite electrodes are investigated through in situ X-ray diffraction measurements.Two kinds of graphite intercalation compounds(GICs)with contrastive intercalation gallery heights(IGHs)have been discovered,which are ascribed to the storage of different kinds of SL-BF_(4)^(-)anions in graphite electrode.The interactions between ions and SL in the electrolyte solutions are characterized by Fourier transform infrared spectroscopy and then correlated with the performance of Li/graphite cells.
基金
financially supported by the National Natural Science Foundation of China,China(21975251)。
作者简介
Corresponding author:Hongyu Wang.E-mail address:hongyuwang@ciac.ac.cn。
