储能科学与技术 ›› 2016, Vol. 5 ›› Issue (5): 713-718.doi: 10.12028/j.issn.2095-4239.2016.0021

• 研究开发 • 上一篇    下一篇

新型固态聚合物电解质在锂硫电池中的研究

马  强1,2,戚兴国1,容晓晖1,胡勇胜1,周志彬2,李  泓1,陈立泉1,黄学杰1   

  1. 1中国科学院物理研究所,北京 100190;2华中科技大学,武汉 430074
  • 收稿日期:2016-06-02 修回日期:2016-06-12 出版日期:2016-09-01 发布日期:2016-09-01
  • 通讯作者: 胡勇胜,研究员,研究方向为新能源材料及其相关基础科学问题,E-mail:yshu@iphy.ac.cn;周志彬,教授,研究方向为锂离子电解质材料,E-mail:zb-zhou@mail.hust.edu.cn。
  • 作者简介:马强(1989—),男,博士研究生,研究方向为锂电池电解质以及器件的研究,E-mail:D201477090@hust.edu.cn;
  • 基金资助:
    国家自然科学基金(51222210,51472268),科技部高科技研究发展计划(863计划)(2009AA033101)及中国科学院“百人计划”项目。

Novel solid polymer electrolytes for all-solid-state lithium-sulfur batteries#br#

MA Qiang1,2, QI Xinguo1, RONG Xiaohui1, HU Yongsheng1, ZHOU Zhibin2, LI Hong1, CHEN Liquan1, HUANG Xuejie1   

  1. 1Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China; 2 Huazhong University of Science and Technology, Wuhan 430074, Hubei, China
  • Received:2016-06-02 Revised:2016-06-12 Online:2016-09-01 Published:2016-09-01

摘要: 本工作采用(氟磺酰)(三氟甲基磺酰)亚胺锂{Li[(FSO2)(CF3SO2)N],LiFTFSI}和聚氧乙烯(PEO)分别作为导电锂盐和聚合物主链,通过简单的溶液浇铸法制备了新型固态聚合物电解质(SPEs),并采取示差扫描量热(DSC)、热重(TGA)、线性扫描伏安(LSV)、交流阻抗(EIS)和恒电位直流(DC)极化等方法研究了LiFTFSI/PEO (EO/Li+摩尔比为16)电解质的理化性质和电化学性质。结果表明,LiFTFSI/PEO电解质具有较高的室温离子电导率(σ ≈10−5 S/cm),较高的氧化电位(4.63 V vs. Li/Li+),并且耐热温度高达256 ℃。锂硫电池测试结果表明,该类SPEs展现出相对高的首周放电比容量(881 mA•h/g),有效地抑制了多硫离子的“穿梭效应”,表现出良好的电池循环性能。

关键词: (氟磺酰)(三氟甲基磺酰)亚胺锂, 固态聚合物电解质, 聚氧乙烯, 锂硫电池

Abstract: Novel solid polymer electrolytes, composed of lithium (fluorosulfonyl)(trifluoromethanesulfonyl) imide {Li[(FSO2)(CF3SO2)N], LiFTFSI} and poly(ethylene oxide) (PEO), are prepared by solution casting method. The physicochemical and electrochemical properties of LiFTFSI/PEO [n(EO)∶n(Li+)=16] electrolyte are investigated by the differential scanning calorimeter (DSC), thermogravimetric analysis (TGA), linear sweep voltammogram (LSV), electrochemical  impedance  spectroscopy (EIS), and potentiostatic direct current (DC) polarization. It is demonstrated that LiFTFSI/PEO electrolyte exhibits a relatively high ionic conductivity (σ≈10−5 S/cm) at 25 ℃, sufficient electrochemical stability (4.63 V vs. Li/Li+), and is thermally stable up to 256 ℃. More importantly, the complex of LiFTFSI/PEO displays a relatively high initial discharge capacity (881 mA•h/g) and effectively inhibits the shuttle effect arising from dissolved polysulfides in lithium-sulfur (Li-S) batteries, and exhibits a good cycling performance of Li-S batteries.

Key words: lithium (fluorosulfonyl)(trifluoromethanesulfonyl) imide, solid polymer electrolytes, poly (ethylene oxide), lithium-sulfur batteries