构筑高倍率钠离子电池的电解液添加剂研究  

Research on an electrolyte additive to improve rate performance of sodium-ion batteries

作　　者：黄雪纯 陈小娟 肖丹[1] 谭光群[1] HUANG Xue-chun;CHEN Xiao-juan;XIAO Dan;TAN Guang-qun(College of Chemical Engineering,Sichuan University,Chengdu 610064,China)

机构地区：[1]四川大学化学工程学院,四川成都610064

出　　处：《化学研究与应用》2024年第11期2640-2647,共8页Chemical Research and Application

基　　金：国家自然科学基金项目(81927809)资助;四川省教育厅研究基金项目(2023YFG0081)资助。

摘　　要：随着钠离子电池的发展,其安全问题也日益受到关注。影响电池安全性的主要原因在于电解液的易燃性。本文将阻燃溶剂磷酸三(2,2,2-三氟乙基)酯(TFEP)作为电解液添加剂引入常用的商业电解液中,以实现高性能和高安全性共存。结果表明,TFEP不仅能作为阻燃溶剂为电解液带来阻燃特性,还能有效提高硬碳的倍率性能和高倍率下的循环能力,在1 C下循环400圈后仍然能够保持100 mAh·g^(-1)的高比容量。TFEP的存在降低了电荷转移电阻,同时能一定程度上抑制盐和溶剂的分解,减小电池极化,这些都证实了TFEP作为多功能添加剂应用于硬碳负极的可行性。With the development of sodium-ion batteries,their safety are increasingly concerned.The main reason affecting the safety of the battery is the flammability of the electrolyte.In this paper,the non-flammable solvent tri(2,2,2-trifluoroethyl)phosphate(TFEP)was introduced into the common commercial electrolyte as an electrolyte additive to achieve high performance and high safety.The results show that TFEP can not only bring flame retardant properties to the electrolyte,but also effectively improve the rate performance of hard carbon and the cycling stability at high rate.Hard carbon in the electrolyte with TFEP can still maintain a high specific capacity of 100 mAh·g^(-1)after 400 cycles at 1 C.The existence of TFEP can reduce the charge transfer resistance,inhibit the decomposition of salt and solvent to a certain extent,and reduce the polarization of the battery,which confirms the feasibility of TFEP as a multi-functional additive applied to the hard carbon negative electrode.

关 键 词：阻燃电解液 扩散动力学 高倍率 钠离子电池 硬碳 

分 类 号：O614.1[理学—无机化学]