Enhanced ionic conductivity and interface stability of hybrid solid-state polymer electrolyte for rechargeable lithium metal batteries
Journal article, 2019

Compared to conventional organic liquid electrolyte, solid-state polymer electrolytes are extensively considered as an alternative candidate for next generation high-energy batteries because of their high safety, non-leakage and electrochemical stability with the metallic lithium (Li) anode. However, solid-state polymer electrolytes generally show low ionic conductivity and high interfacial impedance to electrodes. Here we report a hybrid solid-state electrolyte, presenting an ultra-high ionic conductivity of 3.27 mS cm −1 at room temperature, a wide electrochemical stability window of 4.9 V, and non-flammability. This electrolyte consists of a polymer blend matrix (polyethylene oxide and poly (vinylidene fluoride-co-hexafluoropropylene)), Li + conductive ceramic filler (Li 1.5 Al 0.5 Ge 1.5 (PO 4 ) 3 ) and a solvate ionic liquid (LiFSI in tetra ethylene glycol dimethyl ether, 1:1 in molar ratio) as plasticizer. The introduction of the solvate ionic liquid to the solid-state electrolyte not only improves its ionic conductivity but also remarkably enhances the stability of the interface with Li anode. When applied in Li metal batteries, a Li|Li symmetric cell can operate stably over 800 h with a minimal polarization of 25 mV and a full Li|LiFePO 4 cell delivers a high specific capacity of 158 mAh g −1 after 100 cycles at room temperature.

Interface

Lithium metal anode

High safety

Solid polymer electrolyte

LAGP

Author

Qiao Liu

Xi'an Jiaotong University

Yangyang Liu

Xi'an Jiaotong University

Xingxing Jiao

Xi'an Jiaotong University

Zhongxiao Song

Xi'an Jiaotong University

Matthew Sadd

Xiaoxiong Xu

Zhejiang Funlithium New Energy Technology Co., Ltd.

Aleksandar Matic

Chalmers, Physics, Condensed Matter Physics

Shizhao Xiong

Xi'an Jiaotong University

Chalmers, Physics, Condensed Matter Physics

Jiangxuan Song

Xi'an Jiaotong University

Energy Storage Materials

2405-8297 (eISSN)

Vol. 23 105-111

Subject Categories

Ceramics

Materials Chemistry

Other Chemical Engineering

DOI

10.1016/j.ensm.2019.05.023

More information

Latest update

11/11/2019