Configuration Design and Interface Reconstruction to Realize the Superior High‐Rate Performance for Sodium Layered Oxide Cathodes
Jiandong Zhang, Zhaoshi Yu, Yanbin Zhu, Jingyao Cai, Muqin Wang, Muqin Wang, Pengkun Gao, Yali Zhang, Naiqing Zhang, Deyu Wang, Yan Shen, Mingkui Wang, Mingkui Wang
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.