Highly Concentrated NaN(SO2F)2/3-Methylsulfolane Electrolyte Solution Showing High Na-Ion Transference Number under Anion-Blocking Conditions

被引：9

作者：

Tatara, Ryoichi ^{[1
,4
]}

Okamoto, Yukihiro ^{[1
]}

Ugata, Yosuke ^{[1
]}

Ueno, Kazuhide ^{[1
,2
]}

Watanabe, Masayoshi ^{[1
,2
]}

Dokko, Kaoru ^{[1
,2
,3
]}

机构：

[1] Yokohama Natl Univ, Dept Chem & Life Sci, Hodogaya Ku, 79-5 Tokiwadai, Yokohama, Kanagawa 2408501, Japan

[2] Yokohama Natl Univ, Adv Chem Energy Res Ctr ACERC, Inst Adv Sci, Hodogaya Ku, 79-5 Tokiwadai, Yokohama, Kanagawa 2408501, Japan

[3] Kyoto Univ, Unit Elements Strategy Initiat Catalysts & Batter, Nishikyo Ku, Goryo Ohara, Kyoto 6158245, Japan

[4] Tokyo Univ Sci, Dept Appl Chem, Shinjuku Ku, 1-3 Kagurazaka, Tokyo 1628601, Japan

来源：

ELECTROCHEMISTRY | 2021年 / 89卷 / 06期

基金：

日本学术振兴会;

关键词：

Sodium Batteries; Ligand Exchange; Transference Number; Concentration Polarization; SUPERCONCENTRATED ELECTROLYTES; NEGATIVE ELECTRODES; SODIUM; SOLVATION;

D O I：

10.5796/electrochemistry.21-00095

中图分类号：

O646 [电化学、电解、磁化学];

学科分类号：

081704 ;

摘要：

The performance of a sodium-ion (Na) battery is significantly influenced by its electrolyte characteristics. In particular, the transport properties of the electrolyte have considerable effects on the discharge rate capability. During discharging of a Na battery at high current densities, a concentration gradient of Na salt develops because both cations and anions are mobile in the liquid electrolyte. Concentration polarization can be suppressed by increasing the Na+ transference number (t(Na+)) of the electrolyte. This study demonstrates that highly concentrated NaN(SO2F)(2) dissolved in 3-methylsulfolane (MSL) exhibits a high t(Na+) value of >0.6 under anion-blocking conditions. Raman spectroscopy revealed that Na+ ions formed complexes with MSL and anions in the electrolyte. Na+ ions exchange ligands dynamically and move faster than the ligands, resulting in a high t(Na+). The high t(Na+ )enables a high-rate discharge of the Na battery, despite the low ionic conductivity of the highly concentrated electrolyte. (C) The Author(s) 2021. Published by ECSJ.

引用

页码：590 / 596

页数：7