Tailoring Local Superstructure Units to Mitigate Voltage Decay in Na‐Ion Batteries
Abstract
ABSTRACT The practical application of high‐energy‐density P2‐type cathodes is hindered by severe voltage decay upon high‐potential cycling. This voltage decay primarily originates from irreversible interlayer cation migration and detrimental structural degradation, which can be notably suppressed by regulating the arrangement of superstructure units. Herein, we incorporate LiTiMn 5 superstructure units in P2‐Na 0.7 K 0.04 Li 0.1 Ni 0.22 Mn 0.6 Ti 0.08 O 2 (NaKLNMT) to construct the long‐range in‐plane ordered arrangement within transition metal slabs, creating a stable oxygen coordination environment and high energy barriers along the migration path. Furthermore, the circumscribed P‐type to O‐type stacking evolution and restricted Li/TM migration restrain the formation of vacancy clusters, prohibiting consequential overoxidation of lattice oxygen and inhomogeneous lattice strain accumulation under high‐voltage. Therefore, the target NaKLNMT compound exhibits a negligible voltage decay of 0.15 mV/cycle and 96.3% capacity retention over 100 cycles at 1 C. Our findings demonstrate that regulating cation migration through local superstructure control helps steer strategies to address the issues of voltage decay in sodium‐layered oxide cathodes.
Article Details
Authors (15)
Haojie Dong
Xu Zhu
Center of Nanomaterials for Renewable Energy, State Key Laboratory of Electrical Insulation and Power Equipment, School of Electrical Engineering
Si‐Fan Chen
Center of Nanomaterials for Renewable Energy State Key Laboratory of Electrical Insulation and Power Equipment School of Electrical Engineering Xi'an Jiaotong University Xi'an Shaanxi P. R. China
Haoliang Liu
Chao Li
Shao‐Wen Xu
Center of Nanomaterials for Renewable Energy State Key Laboratory of Electrical Insulation and Power Equipment School of Electrical Engineering Xi'an Jiaotong University Xi'an Shaanxi P. R. China
Guang‐Xu Wei
Center of Nanomaterials for Renewable Energy State Key Laboratory of Electrical Insulation and Power Equipment School of Electrical Engineering Xi'an Jiaotong University Xi'an Shaanxi P. R. China
Yuanguang Xia
Institute of High Energy Physics, Chinese Academy of Sciences
Yongwei Tang
Center of Nanomaterials for Renewable Energy, State Key Laboratory of Electrical Insulation and Power Equipment, School of Electrical Engineering
Yi‐Hu Feng
Center of Nanomaterials for Renewable Energy State Key Laboratory of Electrical Insulation and Power Equipment School of Electrical Engineering Xi'an Jiaotong University Xi'an Shaanxi P. R. China
Mengting Liu
Center of Nanomaterials for Renewable Energy, State Key Laboratory of Electrical Insulation and Power Equipment, School of Electrical Engineering
Kai Chen
Bing Xiao
Department of Orthopaedics
Yonghong Cheng
Peng‐Fei Wang
Center of Nanomaterials for Renewable Energy State Key Laboratory of Electrical Insulation and Power Equipment School of Electrical Engineering Xi'an Jiaotong University Xi'an Shaanxi P.R. China