Regulation of anion-Na+ coordination chemistry in electrolyte solvates for low-temperature sodium-ion batteries

• 成果类型: Article
• 署名作者: Zhou, Xunzhu; Huang, Yaohui; Wen, Bo; Yang, Zhuo; Hao, Zhiqiang; Li, Lin; Chou, Shu-Lei; Li, Fujun
• 署名单位: Nankai University; Wenzhou University; Nankai University; Haihe Laboratory of Sustainable Chemical Transformations
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-9367
• DOI: 10.1073/pnas.2316914121
• 发表日期: 2024-01-30

摘要

High- performance sodium storage at low temperature is urgent with the increasingly stringent demand for energy storage systems. However, the aggravated capacity loss is induced by the sluggish interfacial kinetics, which originates from the interfacial Na+ desolvation. Herein, all- fluorinated anions with ultrahigh electron donicity, trifluoroacetate (TFA-), are introduced into the diglyme (G2) - based electrolyte for the anion- reinforced solvates in a wide temperature range. The unique solvation structure with TFA- anions and decreased G2 molecules occupying the inner sheath accelerates desolvation of Na+ to exhibit decreased desolvation energy from 4.16 to 3.49 kJ mol-1 and 24.74 to 16.55 kJ mol-1 beyond and below -20 degrees C, respectively, compared with that in 1.0 M NaPF6-G2. These enable the cell of Na||Na3V2(PO4)3 to deliver 60.2% of its room- temperature capacity and high capacity retention of 99.2% after 100 cycles at -40 degrees C. This work highlights regulation of solvation chemistry for highly stable sodium - ion batteries at low temperature.