储能科学与技术 ›› 2016, Vol. 5 ›› Issue (5): 719-724.doi: 10.12028/j.issn.2095-4239.2016.0034

• 研究开发 • 上一篇    下一篇

基于LLZO的复合电解质对Li-S电池穿梭效应的抑制

郑鸿鹏1,陈  挺1,徐比翼1,田  然1,刘河洲1,段华南1,王  可2,吴勇民2   

  1. 1上海交通大学材料科学与工程学院,金属基复合材料国家重点实验室,上海 200240;2上海空间电源研究所,空间电源技术国家重点实验室,上海 200245
  • 收稿日期:2016-07-01 修回日期:2016-07-06 出版日期:2016-09-01 发布日期:2016-09-01
  • 通讯作者: 段华南,副教授,研究方向为储能材料、薄膜材料、高通量实验,E-mail:hd1@sjtu.edu.cn;吴勇民,工程师,研究方向为全固态锂电池、固态电解质、正极材料,E-mail:wuym2014@126.com。
  • 作者简介:郑鸿鹏(1993—),男,本科在读,研究方向为固态电解质,新型锂电池,E-mail:1186356597@qq.com;
  • 基金资助:
    国家自然科学基金项目(11304198),航天先进技术联合研究中心技术创新项目(USCAST-2015-40),上海交通大学材料基因组联合研究中心项目(15X190030002)。

LLZO-based hybrid electrolyte to suppress the shuttle effect of Li-S battery

LLZO-based hybrid electrolyte to suppress the shuttle effect of Li-S battery#br#   

  1. 1State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China; 2State Key Laboratory of Spcae Power Technology, Shanghai Institute of Space Power-Sources, Shanghai 200245, China
  • Received:2016-07-01 Revised:2016-07-06 Online:2016-09-01 Published:2016-09-01

摘要: 相对于传统锂离子电池,锂硫电池具有高比容量、高能量密度、环境友好等特点,因而在作为未来的动力电池和储能电池上被寄予厚望。但是,目前的锂硫电池存在穿梭效应、硫利用率低、充放电体积变化大等问题。本工作主要针对硫的穿梭效应、硫在负极材料沉积等问题开展研究。首先制备出室温离子传导率为6.4×10-4 S/cm的含锂石榴石(LLZO)固态电解质;再引入LLZO固态电解质作为隔膜,使用石墨烯气凝胶复合硫正极组装电池进行测试。充放电循环测试结果表明,该电池结构可以解决锂硫电池难以有效充电的问题,获得了接近100%的库仑效率。此外,采用XRD、SEM等检测手段分析了充放电循环后LLZO隔膜的微观物相结构,证明了LLZO能够有效阻挡多硫化物,抑制穿梭效应。

关键词: LLZO, 锂硫电池, 氧化石墨烯, 穿梭效应, 库仑效率

Abstract: Compared with traditional lithium-ion batteries, lithium-sulfur (Li-S) batteries have many advantages such as high specific capacity, high energy density and environment-friendly characteristic, which makes them a promising system for electric vehicles and energy storage. However, the Li-S batteries have been facing problems, such as the shuttle effect, low efficiency, and volume change during cycling. In this paper, we try to suppress the shuttle effect by introducing a LLZO-based hybrid electrolyte. Firstly, we prepare the dense LLZO solid electrolyte with the ionic conductivity of 6.4×104 S/cm; then we use the LLZO as the separator, Li anode, and S-C composite cathode to assemble Li-S test cells. The electrochemical test results indicate that the cell can obtain a Coulomb efficiency closely to 100%. The post-test examination shows that element S can only be found on the side of LLZO facing the S-C cathode, not on the side facing the Li anode, suggesting that the LLZO can effectively block the transport of the dissolved polysulfides.

Key words: LLZO, Li-S battery, oxidized graphene, the shuttle effect, coulomb efficiency