Energy Storage Science and Technology ›› 2020, Vol. 9 ›› Issue (6): 1629-1640.doi: 10.19799/j.cnki.2095-4239.2020.0144

• Energy Storage Materials and Devices • Previous Articles     Next Articles

Research progress of electrolyte optimization for lithium metal batteries

Jianwen FENG1(), Shiguang HU1,3, Bing HAN2, Yinglin XIAO2, Yonghong DENG2(), Chaoyang WANG1()   

  1. 1.Research Institute of Materials Science, South China University of Technology, Guangzhou 510640, Guangdong, China
    2.Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, Guangdong, China
    3.Shenzhen Capchem Technology Co. , Ltd. , Shenzhen 518118, Guangdong, China
  • Received:2020-04-15 Revised:2020-04-23 Online:2020-11-05 Published:2020-10-28
  • Contact: Yonghong DENG,Chaoyang WANG E-mail:738326612@qq.com;yhdeng08@163.com;zhywang@scut.edu.cn

Abstract:

As an anode material, the Li metal battery with metallic lithium has attracted tremendous attention for its extremely high-energy density. However, the development of Li metal batteries has been hindered by the parasitic reactions between metallic lithium and organic electrolytes and the uncontrolled growth of dendritic lithium, which brings serious safety hazards to Li metal batteries. The root causes of these challenges are the unstable solid electrolyte interphase (SEI) layer formed on the metallic lithium surface and the inhomogeneous Li deposition. Liquid electrolyte is a key component of a lithium metal battery. The compatibility of the liquid electrolyte with the lithium metal anode and the property of the liquid electrolyte determine the practicality of the lithium metal battery. This review first introduces the function mechanism of the liquid electrolyte in lithium metal batteries and presents recent progress of electrolyte regulation for Li metal batteries from three aspects of additives, conductive lithium salts, and organic solvents. The film-forming additives and those manipulating the lithium deposition behavior for liquid electrolyte additives are highlighted. Three strategies for conductive lithium salts are introduced: novel lithium salts; mixed lithium salts; and regulation of the lithium salt concentration. For organic solvents, the effects of carbonate, phosphate, and ether solvents on lithium metal batteries are introduced. Electrolyte optimization proves its effectiveness in regulating the Li deposition behavior and the SEI layer composition, which is one of the most facile and effective strategies for alleviating the abovementioned issues. Finally, we prospect the future research directions in this field.

Key words: lithium metal battery, lithium metal anode, electrolyte

CLC Number: