Evolution of the electrochemical interface in sodium ion batteries with ether electrolytes

Ether based electrolytes have surfaced as alternatives to conventional carbonates allowing for enhanced electrochemical performance of sodium-ion batteries; however, the primary source of the improvement remains poorly understood. Here we show that coupling titanium dioxide and other anode materials with diglyme does enable higher efficiency and reversible capacity than those for the combination involving ester electrolytes. Importantly, the electrolyte dependent performance is revealed to be the result of the different structural evolution induced by a varied sodiation depth. A suit of characterizations show that the energy barrier to charge transfer at the interface between electrolyte and electrode is the…

• NN
  National Natural Science Foundation of China

  Awards: U1601206, U1710256, D16002, 51772164, 51525204
• SA
  State Administration of Foreign Experts Affairs

  Award: D16002
• HE
  Higher Education Discipline Innovation Project

  Award: D16002
• GP
  Guangdong Provincial Pearl River Talents Program

  Award: 2017BT01N111
• NS
  National Science Fund for Distinguished Young Scholars

  Awards: U1710256, 51525204