高等学校化学学报 ›› 2011, Vol. 32 ›› Issue (11): 2645.

• 研究论文 • 上一篇    下一篇

硝酸锂作添加剂对锂硫电池电化学性能的影响

熊仕昭, 谢凯, 洪晓斌   

  1. 国防科学技术大学航天与材料工程学院材料工程与应用化学系, 长沙 410073
  • 收稿日期:2010-12-01 修回日期:2011-03-30 出版日期:2011-11-10 发布日期:2011-10-14
  • 通讯作者: 谢凯 E-mail:xie_kai@hotmail.com

Effect of LiNO3 as Additive on Electrochemical Properties of Lithium\|sulfur Batteries

XIONG Shi-Zhao, XIE Kai*, HONG Xiao-Bin   

  1. Department of Material Engineering and Applied Chemistry, College of Aerospace and Material Engineering, National University of Defense Technology, Changsha 410073, China
  • Received:2010-12-01 Revised:2011-03-30 Online:2011-11-10 Published:2011-10-14
  • Contact: XIE Kai E-mail:xie_kai@hotmail.com

摘要: 采用充放电测试和交流阻抗测试研究了硝酸锂作电解液添加剂对锂硫电池电化学性能的影响. 采用电子扫描显微镜观察分析了添加剂对锂负极的影响, 探讨了硝酸锂的作用机理.  结果表明, 采用硝酸锂作为锂硫电池电解液的添加剂, 可以在锂负极表面形成具有钝化负极活性表面及保护锂负极的界面膜.  该膜可以抑制电解液中高价态聚硫离子与锂负极的副反应, 避免在锂负极表面形成不可逆的硫化锂, 从而提高锂硫电池的循环性能和放电容量. 采用硝酸锂作添加剂的锂硫电池首次放电比容量达1172 mA?h/g, 循环100次比容量保持为629 mA?h/g.

关键词: 硝酸锂, 添加剂, 锂负极, 界面膜, 锂硫电池

Abstract: The effect of LiNO3 as additive on electrochemical properties of lithium-sulfur batteries was investigated by charge-discharge and electrochemical impedance spectroscopy(EIS). The effect of LiNO3 on lithium anode was investigated by scanning electron microscope(SEM) and the interacting mechanisms of LiNO3 was discussed. It was found that LiNO3 adopted as additive of electrolyte formed protective surface film on lithium electrode. The film resulted in passivation at the surface of the electrode and prevented the parasitic reaction between higher-order polysulfide and lithium electrode. Cycle life and capacity of lithium-sulfur batteries were improved because the film prevented the formation of irreversible Li2S on lithium electrode. The initial discharge capacity of lithium sulfurbatteries with LiNO3 is 1172 mA·h/g. A reversible capacity of 629 mA·h/g  after 100 cycles was obtained.

Key words: LiNO3, Additive, Lithium anode, Interface film, Lithium-sulfur battery

TrendMD: