Page 173 - 《精细化工》2021年第10期

第 38 卷第 10 期 精 细 化 工 Vol.38, No.10
2021 年 10 月 FINE CHEMICALS Oct. 2021

有机电化学与工业
一种能够抑制锂枝晶的锂金属电池

电解液润湿性添加剂

*
徐继开，刘元生，单忠强
（天津大学 化工学院，天津 300350）

摘要：将氟代有机溶剂 2,2,3,3-四氟丙基甲基丙烯酸酯（TFPMA）作为双功能添加剂引入碳酸酯电解液体系，考
察了 TFPMA 质量分数对增大润湿性的影响。采用交流阻抗、恒流充放电等测试了添加 TFPMA 后的锂金属电池
性能。采用 SEM 和 XPS 表征了循环后的锂金属电极表面。结果表明，1.0%（质量分数，下同）TFPMA 的添加
使电解液与隔膜间的接触角从 54°降至 44°，内阻从 6.15 Ω降至 1.94 Ω，Li-LiFePO 4 电池在 5 C 电流密度下的
比容量从 66 mA·h/g 提升至 80 mA·h/g，1 C 电流密度下的恒电流循环在 100 圈时还保持 99%以上的库仑效率。
+
TFPMA 还促进了 Li 的均匀沉积和优良固体电解质界面膜的形成，抑制了锂枝晶，电解液添加了 1.0% TFPMA
后，Li-Cu 电池可以循环 100 圈以上，而库仑效率没有发生较大下降。循环后电极的 SEM 图表明，添加了 1.0%
TFPMA 电解液的锂金属负极表面沉积更加平整，有较少的锂枝晶生成。
关键词：锂金属电池；电解液；润湿性；氟代有机溶剂添加剂；锂枝晶抑制；有机电化学
中图分类号：TM912 文献标识码：A 文章编号：1003-5214 (2021) 10-2103-09

A dual-function electrolyte additive for wettability improvement and
dendrites suppression in lithium metal batteries

*
XU Jikai, LIU Yuansheng, SHAN Zhongqiang
（School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China）

Abstract: Fluorinated organic solvent 2,2,3,3-tetrafluoropropyl methacrylate (TFPMA) as a dual-function
additive was introduced into the carbonate electrolyte system, and the effect of TFPMA mass fraction on
increasing wettability was investigated. The performance of lithium metal battery after adding TFPMA was
tested by using AC impedance and constant current constant current charge and discharge. The surface of
the lithium metal electrode after cycling was characterized by SEM and XPS. The results showed that after
adding 1.0% (mass fraction, the same below) TFPMA, the contact angle between electrolyte and diaphragm
decreased from 54° to 44°, the internal resistance decreased from 6.15 Ω to 1.94 Ω, the specific capacity of
Li-LiFePO 4 battery at a current density of 5 C increase from 66 mA·h/g to 80 mA·h/g, and the coulombic
efficiency of more than 99% maintained after 100 cycles at a current density of 1 C. TFPMA also promoted
+
the uniform deposition of Li and the formation of excellent solid electrolyte interface film, and inhibited
lithium dendrites. After adding 1.0% TFPMA, Li-Cu battery could circulate more than 100 cycles without
significant drop in coulombic efficiency. SEM images of the electrode after circulating indicated that the
lithium metal negative electrode added with 1.0% TFPMA electrolyte had a smoother surface deposition
and less lithium dendrites.
Key words: lithium metal batteries; electrolyte; wettability; fluorinated organic solvent additives; lithium
dendrites suppression; electro-organic chemistry

收稿日期：2021-05-18; 定用日期：2021-07-26; DOI: 10.13550/j.jxhg.20210508
基金项目：国家重点研发计划（2016YFB0100511）
作者简介：徐继开（1996—），男，硕士生，E-mail：xujikailemon@163.com。联系人：单忠强（1957—），男，教授，E-mail：shanzq@
tju.edu.cn。