Configuration Design and Interface Reconstruction to Realize the Superior High‐Rate Performance for Sodium Layered Oxide Cathodes

Abstract

Abstract Charge transfer at the electrode/electrolyte interface and mass transfer within the electrode are the two main factors affecting the high‐rate performance of O3‐type layered oxide cathodes for sodium‐ion batteries. Here a multidimensional lanthurization strategy is proposed to construct the surface LaCrO 3 heterostructure and create a Cr─O─La configuration for O3‐type NaCrO 2 . The electrified heterogeneous LaCrO 3 induces a built‐in electric field to accelerate charge transfer at the interface. Meanwhile, the Cr─O─La configuration in the transition metal layer leads to local charge aggregation, weakens the interaction force between Na─O, and reduces the Na + migration barrier. This strategy significantly improves the electrochemical reaction kinetics and the structural reversibility of the layered oxide cathode. As a result, the designed stoichiometric ratio Na 0.94 Cr 0.98 La 0.02 O 2 electrode exhibits remarkable rate performance (101.8 mAh g −1 at 40 C) as well as outstanding cycling stability (83.1% capacity retention at 20 C for 2000 cycles) in a half‐cell, along with a competitive full battery performance (89.3% after 500 cycles at 2 C). This study provides a promising route to achieve capacity presentation and retention of layered oxide cathode materials at high‐rate.