Electrode–Electrolyte Interfacial Chemistry Modulation for Ultra‐High Rate Sodium‐Ion Batteries

Abstract Sodium‐ion batteries capable of operating at rate and temperature extremes are highly desirable, but elusive due to the dynamics and thermodynamics limitations. Herein, a strategy of electrode–electrolyte interfacial chemistry modulation is proposed. The commercial hard carbon demonstrates superior rate performance with 212 mAh g −1 at an ultra‐high current density of 5 A g −1 in the electrolyte with weak ion solvation/desolvation, which is much higher than those in common electrolytes (nearly no capacity in carbonate‐based electrolytes). Even at −20 °C, a high capacity of 175 mAh g −1 (74 % of its room‐temperature capacity) can be maintained at 2 A g −1 . Such an electrode retains 90 % of its initial…

• NN
  National Natural Science Foundation of China

  Award: 21905306, 21975289, and U19A2019