Research on modification of layered oxide cathode materials for sodium-ion battery driven by high-entropy strategy: progress, mechanism, and future

doi:10.11949/0438-1157.20250511

Abstract

Abstract:

In recent years, sodium-ion batteries (SIB) have received more and more attention due to its cost advantage and potential as an alternative to lithium-ion batteries (LIB). Layered oxide cathodes, as the most promising sodium-ion cathode materials, offer advantages such as high theoretical specific capacity and simple synthesis processes. However, they also suffer from drawbacks such as irreversible phase transitions, structural degradation, and voltage decay, which hinder the commercial development and large-scale application of SIBs. The high-entropy strategy is a comprehensive modification strategy that combines multiple methods, including multi-element doping and bulk structure design, to effectively improve electrode material performance indicators such as energy density, long-term cycle stability, and ion transport kinetics. This review systematically summarizes recent achievement in high-entropy strategies for modification of layered oxide cathode materials for SIB. The intrinsic correlation and modification mechanism between high-entropy effect and improved electrochemical performance are analyzed. Furthermore, future directions for high-entropy strategy are prospected, providing new insight for the design and synthesis of high-performance layered cathode material for future sodium-ion batteries.

Key words: sodium-ion battery, layered oxide materials, entropy, phase change, electrochemistry

摘要：

近年来，钠离子电池（SIB）因其成本优势和对锂离子电池的替代作用而受到了越来越多的关注。层状氧化物正极作为最有潜力的钠电正极材料，具有理论比容量高、合成工艺简单等优势，但也存在着不可逆相变、结构退化以及电压衰减等缺陷，这些因素阻碍了SIB的商业化发展与大规模应用。高熵策略是一种结合了多元素掺杂、体相结构设计等多种手段的综合改性策略，可以有效提高电极材料的能量密度、长循环稳定性以及离子传输动力学等性能指标。总结了近年来高熵策略在钠离子电池层状氧化物材料改性研究领域的前沿成果，探讨了高熵效应与层状氧化物材料电化学性能之间的内在联系与作用机理，并展望了高熵策略未来的发展方向，为未来高性能钠离子电池层状正极材料的设计与合成提供新的见解。

关键词: 钠离子电池, 层状氧化物, 熵, 相变, 电化学

CLC Number:

TM 912

Yifan TONG, Ningshuang ZHANG, Xingpeng CAI, Chengyu LI, Shiyou LI. Research on modification of layered oxide cathode materials for sodium-ion battery driven by high-entropy strategy: progress, mechanism, and future[J]. CIESC Journal, 2025, 76(12): 6218-6235.

童逸凡, 张宁霜, 蔡星鹏, 李成煜, 李世友. 高熵策略驱动下的钠离子电池层状氧化物正极材料改性研究：进展、机理与展望[J]. 化工学报, 2025, 76(12): 6218-6235.

Figures/Tables 12

Table 1 Summary of advantages and disadvantages of mainstream SIB cathode materials

材料	优势	劣势
聚阴离子型材料^[9]	结构稳定性强、工作电压高	电子电导率低，能量密度低，合成成本高昂
普鲁士蓝材料^[10]	合成工艺简单、快速充放电能力强	循环寿命较短、工作温度范围较窄
过渡金属氧化物材料^[11]	合成工艺简单、可逆比容量高、储钠能力强	充放电过程中易发生不可逆相变、空气稳定性差

Table 2 Summary of layered cathodes with high-entropy configurations in SIBs

正极材料	放电比容量/(mAh·g^-1)	电压范围/V	循环稳定性	倍率性能/(mAh·g^-1)	文献
Na_0.83Li_0.1Ni_0.25Co_0.2Mn_0.15Ti_0.15Sn_0.15O_2-_δ	109.4	2.0~4.2	87.2%/200次循环/2.0C	83.3 /10C	[35]
NaCu_0.1Ni_0.25Co_0.15Mn_0.35Li_0.05Ti_0.05Sn_0.05O₂	144.5	2.2~4.4	90.1%/100次循环/1.0C	76.7/5.0C	[36]
NaNi_0.3Cu_0.1Fe_0.2Mn_0.3Ti_0.1O₂	141.5	2.0~4.0	85%/500次循环/1.0C	120/5.0C	[37]
NaNi_0.2Fe_0.2Mn_0.35Cu_0.05Zn_0.1Sn_0.1O₂	128	2.0~4.0	87%/500次循环/3.0C	64.3/2.0C	[38]
Na_2/3Li_1/6Fe_1/6Co_1/6Ni_1/6Mn_1/3O₂	171.2	2.0~4.5	90%/30次/0.3C	78.2/10C	[39]
[Na_0.67Zn_0.05]Ni_0.22Cu_0.06Mn_0.66Ti_0.01O₂	146.1	2.0~4.3	92.7%/100次循环/1.0C	91.54/10C	[40]
Na_0.67Mn_0.6Cu_0.08Ni_0.09Fe_0.18Ti_0.05O₂	150.3	2.0~4.5	100%/500次循环/10C	62.5/10C	[41]
Na[FeCoNiTi]_1/6Mn_1/4Zn_1/12O₂	127.3	2.0~4.1	88%/1000次循环/1.0C	30.7/10C	[42]
Na_0.9Ni_0.2Fe_0.2Co_0.2Mn_0.2Ti_0.15Cu_0.05O₂	117.8	2.2~4.1	70.7%/1000次循环/1.0C	98.6/10C	[43]
Na(Fe_0.2Co_0.15Cu_0.05Ni_0.2Mn_0.2Ti_0.2)B_0.02O₂	120.5	2.0~4.1	95%/100次循环/1.0C	103.3/2.0C	[44]
Na_0.95Li_0.06Ni_0.25Cu_0.05Fe_0.15Mn_0.49O₂	141.2	2.0~4.2	83.2/500次循环/8.0C	83.5/20C	[45]
Na_0.89Li_0.05Cu_0.11Ni_0.11Fe_0.3Mn_0.43O_1.97F_0.03	145	1.5~4.0	80%/300次循环/1.0C	109/10C	[46]
Na_0.85Li_0.05Ni_0.25Cu_0.025Mg_0.025Fe_0.05Al_0.05Mn_0.5Ti_0.05O₂	122	2.0~4.3	89%/1000次循环/10C	81.8/10C	[47]
Na_0.85Li_0.05Ni_0.3Fe_0.1Mn_0.5Ti_0.05O₂	182.2	1.5~4.3	94.3/10次循环/10C	68.4/10C	[48]

Fig.1 Entropy-optimized structural evolution during Na+ extraction/insertion[35]

Fig.2 Schematic diagram of stabilizing lattice oxygen through high-entropy modification[36]

Fig.3 The structural evolution and density functional theory (DFT) calculations of HE and NFM cathode materials[38]

Fig.4 (a) Schematic illustration of charge/discharge behaviors for high-entropy and superlattice-stabilized O3-type cathodes proposed in this work,where the O3-P3 phase transition at the low-voltage region is facilitated and the P3-O3 phase transition at the high-voltage region is suppressed; (b) Electrochemical performance comparison between NaLFCNM and previously reported O3/P3-type cathodes, in which all cathodes havebeen cycled for more than 50 cycles[39]

Fig.5 (a) The optimized structures of entropy-tuned NZNCMTO; (b) Comparison of COHP values of Ni—O and Mn—O bonds in NZNCMTO and NNMO; (c) COHP results of entropy-tuned NZNCMTO; (d)—(g) Schematic diagram of the migration paths and migration energy barrier of sodium ions through Ni/Mn, Ti, and Cu in NNMO and entropy-tuned NZNCMTO; (h) Total density of states (DOS) of NNMO and (i) entropy-tuned NZNCMTO of the initial state[40]

Fig.6 Charge compensation mechanism of MCNFT[41]

Fig.7 The kinetic performance and full cell of FCNTMZ1/12//HC[42]

Fig.8 Structural comparison between high-entropy and low-entropy sodium layered oxides[43]

Fig.9 Structure characterization of Na0.95LNCFM materials[45]

Fig.10 Redox mechanism and crystal structural evolution: (a)—(d) Normalized Cu, Ni, Fe, and Mn K-edge XANES spectra at different charge- discharge states; (e)—(g) Voltage profile and corresponding in situ XRD evolution of CNFM, LCNFM, and LCNFMF; (h) The a/c-lattice parameters change in the three samples obtained by fitting the in situ XRD data; (i) Schematic illustration of the crystal structural evolution at the end of charging of LCNFM and LCNFMF[46]

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