Investigating the Correlation of Segmental Dynamics, Free Volume Characteristics, and Ionic Conductivity in Poly(ethylene oxide)-Based Electrolyte: A Broadband Dielectric and Positron Annihilation Spectroscopy Study

被引：35

作者：

Utpalla, P. ^{[1
,2
]}

Sharma, S. K. ^{[1
,2
]}

Sudarshan, K. ^{[1
,2
]}

Deshpande, S. K. ^{[3
]}

Sahu, M. ^{[4
]}

Pujari, P. K. ^{[1
,2
]}

机构：

[1] Bhabha Atom Res Ctr, Radiochem Div, Mumbai 400085, Maharashtra, India

[2] Homi Bhabha Natl Inst, Mumbai 400094, Maharashtra, India

[3] UGC DAE Consortium Sci Res, Mumbai 400085, Maharashtra, India

[4] Bhabha Atom Res Ctr, Radioanalyt Chem Div, Mumbai 400085, Maharashtra, India

来源：

JOURNAL OF PHYSICAL CHEMISTRY C | 2020年 / 124卷 / 08期

关键词：

GLASS-TRANSITION TEMPERATURE; LOCAL FREE-VOLUME; POLYMER ELECTROLYTES; SALT-CONCENTRATION; AC CONDUCTIVITY; ELECTROCHEMICAL PROPERTIES; MECHANICAL-PROPERTIES; LITHIUM BATTERIES; TRANSPORT; RELAXATION;

D O I：

10.1021/acs.jpcc.9b11722

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Poly(ethylene oxide), PEO, based solid polymer electrolyte with different loadings of a lithium salt, lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), has been investigated to study the role of PEO-Li cross-linking on segmental dynamics and free volume structure of PEO which consequently determine thermal, mechanical, and ion conduction properties of the electrolyte. In order to investigate the interrelation between segmental dynamics, free volume structure, and ion conduction mechanism, broadband dielectric spectroscopy and positron annihilation spectroscopy have been employed. The ion conduction process in the polymer electrolyte has been explained according to Almond-West formalism considering two different universalities dominating at different temperature or frequency regimes. Ionic conductivity was observed to increase in a nonlinear trend with salt loading, confirming the additional role of the ion diffusion process. The present study has shown that segmental dynamics and free volume structure of PEO-electrolyte which primarily govern the ion diffusion process are interrelated. These have been invoked to explain the observed variations in ionic conductivity, crystallinity, ductility, and thermal stability of PEO-LiTFSI electrolytes.

引用

页码：4489 / 4501

页数：13

共 94 条

[1] THE EXTRACTION OF IONIC CONDUCTIVITIES AND HOPPING RATES FROM AC CONDUCTIVITY DATA [J].