高等学校化学学报Issue(2)：306-315,10.DOI:10.7503/cjcu20150704
Li1.5Al0.5Ge1.5（PO4）3基固体复合电解质的制备及锂离子导电行为
Preparation and Lithium Ion Transport Behavior for Li1. 5 Al0. 5 Ge1. 5(PO4) 3 Based Solid Composite Electrolyte
余涛 1韩喻 1王珲 1熊仕昭 1谢凯 1郭青鹏1
作者信息
- 1. 国防科学技术大学航天科学与工程学院材料科学与工程系，长沙 410073
- 折叠
摘要
Abstract
LAGP-PEO ( LiTFSI) solid composite electrolyte were prepared with Li1. 5 Al0. 5 Ge1. 5 ( PO4 ) 3 (LAGP) and LiN( CF3 SO2 ) 2 ( LiTFSI) as conductive components and poly( ethylene oxide) ( PEO) as the binder using solution casting method. The molar ratio of EO/ Li was 13 when the ratio of PEO to LAGP was varied. The role of LAGP and the transport mechanism of Li-ion in solid composite electrolyte were analyzed using electrochemical impedance spectroscopy and morphology techniques. The results showed that LAGP partially interacted to PEO(LiTFSI) and uniformly distributed in the electrolyte. With the increase of LAGP content, amorphous regions of PEO rises up to a maximum value due to the coordination interactions between LAGP and PEO(LiTFSI). Three phases are generally present, namely a pure crystalline LAGP phase, all amorphous complexion PEO( LiTFSI) phase and a transition phase consisting of lithium salt particles and amorphous PEO(LiTFSI). The electrochemical impedance spectroscopy(EIS) showed that Li+ ions can go through the interface between ceramic particles and polymer. Compared with other ceramic fillers ( SiO2 , Al2 O3 ), the addition of Li+conducting LAGP improves the ionic conductivity and electrochemical stability of PEO-based solid composite electrolyte. LAGP glass-ceramic improves solid composite electrolyte conductivity not only by enhancing the amorphous PEO phase, but also via its intrinsic conductivity. The highest ionic con-ductivity and the processability of LAGP-PEO(LiTFSI) solid electrolyte were obtained when the mass ratio of LAGP to PEO was fixed at 6 : 4. The optimal ionic conductivity can reach 2. 57×10-5 S / cm at room tempera-ture which is close to that of LAGP. In addition, LAGP-PEO(LiTFSI) solid composite electrolyte shows an enlarged electrochemical stability window( >5 V) in comparison to the PEO( LiTFSI) polymer electrolyte. Solid composite electrolyte based on LAGP-PEO(LiX) has a great prospect in application due to the combina-tion of the fast ion conductor LAGP with high ionic conductivity and the PEO-based polymer electrolyte with good processability.关键词
固体复合电解质/Li1.5Al0.5Ge1.5(PO4)3/聚氧化乙烯/离子电导率Key words
Solid composite electrolyte/Li1. 5 Al0. 5 Ge1. 5(PO4 ) 3(LAGP)/Poly(ethylene oxide)(PEO)/Ionic conductivity分类
化学化工引用本文复制引用
余涛,韩喻,王珲,熊仕昭,谢凯,郭青鹏..Li1.5Al0.5Ge1.5（PO4）3基固体复合电解质的制备及锂离子导电行为[J].高等学校化学学报,2016,(2):306-315,10.
