Abstract
Titanates have been widely reported as anode materials for sodium‐ion batteries (SIBs). However, their wide temperature suitability and cycle life remain fundamental issues that hinder their practical application. Herein, a novel hollow Na2Ti3O7 microsphere (H‐NTO) with a unique chemically bonded NTO/C(N) interface is reported. Theoretical calculations demonstrated that the NTO/C(N) interface stabilizes the crystal structure, and the optimized interface enables the H‐NTO anode to stably operate for 80 000 cycles in a conventional ester electrolyte with negligible capacity loss. Optimizing the electrolyte allows the H‐NTO electrode to cycle stably for 200 calendar days without capacity degradation at −40 °C. The excellent cycling stability is attributed to the NTO/C(N) interface and the stable solid electrolyte interphase formed by the highly adaptable electrolyte/electrode interface. Titanate exhibits solvent co‐intercalation behavior in ether‐based electrolytes, and its robust structure ensures that it can adapt to large volume changes at low temperatures. This study provides a unique perspective on the long‐cycle mechanism of titanate anodes and highlights the critical importance of manipulating the interfacial chemistry in SIBs, including the material and electrode/electrolyte interfaces.
Funding Information
  • National Natural Science Foundation of China (11872087)
  • Natural Science Foundation of Beijing Municipality (2182033)
  • Aeronautical Science Foundation of China (2016ZF51054)
  • Higher Education Discipline Innovation Project (B14009)
  • Fundamental Research Funds for the Central Universities (YWF‐19‐BJ‐J‐55)

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