鈉離子電池層狀氧化物正極材料研究進展

菅夏琰; 金俊騰; 王瑤; 沈秋雨; 劉永暢

doi:10.13374/j.issn2095-9389.2021.05.26.001

鈉離子電池層狀氧化物正極材料研究進展

doi: 10.13374/j.issn2095-9389.2021.05.26.001

菅夏琰¹,
金俊騰¹,
王瑤¹,
沈秋雨¹,
劉永暢^{1, 2, 3, ,}

1.
北京科技大學新材料技術研究院，北京 100083
2.
北京材料基因工程高精尖創新中心，北京 100083
3.
北京科技大學新金屬材料國家重點實驗室，北京 100083

基金項目: 國家自然科學基金資助項目（22075016，21805007）；中央高校基本科研業務費資助項目（FRF-TP-20-020A3）

詳細信息

通訊作者:
E-mail: liuyc@ustb.edu.cn

中圖分類號: O646.2;TM911.3
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出版歷程
- 收稿日期: 2021-05-26
- 網絡出版日期: 2021-08-05
- 刊出日期: 2022-04-02

Recent progress on layered oxide cathode materials for sodium-ion batteries

1.
Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083, China
2.
Beijing Advanced Innovation Center for Materials Genome Engineering, Beijing 100083, China
3.
State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083, China

More Information

Corresponding author: E-mail: liuyc@ustb.edu.cn

摘要

摘要: 鈉離子電池憑借資源和成本優勢在大規模儲能和低速電動車領域展現出極大應用前景。層狀氧化物理論容量較高且易于合成，是目前最具應用潛力的鈉離子電池正極材料之一。如何改善層狀氧化物正極材料的循環穩定性并提升其能量密度是當前的科學前沿問題。首先，綜述了層狀氧化物正極材料的幾種典型改性方法，從組分設計的角度，探討了不同摻雜元素、不同摻雜位點對材料容量和循環壽命的影響，闡述了利用陰離子反應提供額外容量的基本原理，概述了提高陰離子氧化還原可逆性的摻雜策略；從結構設計的角度，介紹了復合相材料的制備、微觀結構的設計和調控等方向的最新進展；從表面設計的角度，討論了金屬氧化物、磷酸鹽等作為包覆層對改善材料穩定性和倍率性能的作用機制。最后，總結了層狀氧化物儲鈉正極材料現階段面臨的挑戰，并對其未來的發展方向進行了展望，提出了新的研究思路。
- 鈉離子電池 /
- 正極材料 /
- 層狀氧化物 /
- 改性手段 /
- 陰離子氧化還原
Abstract: Driven by the national strategic goal of “emission peak and carbon neutrality”, developing grid-scale energy storage systems (ESSs) for high-efficiency utilization of renewable clean energy is of great importance and urgency. Currently, lithium-ion batteries (LIBs) are being widely used in portable electronics and electric vehicles markets due to their high energy density and long cycling life. Nevertheless, the ever-increasing price and uneven distribution of lithium resources limit the further applications of LIBs for large-scale ESS. Recently, sodium-ion batteries (SIBs) have gained tremendous attention as promising large-scale energy storage devices and low-speed electric vehicle power sources, owing to the low-cost and abundant sodium reserves. However, the larger size and heavier mass of Na⁺ than those of Li⁺ commonly lead to sluggish reaction kinetics, severe volume expansion, and the undesirable structural failure of electrode materials upon charge/discharge, which hinder the commercial value of SIBs. Leveraging high-performance cathode materials is expected to boost the development of SIBs because cathodes largely determine the cost and electrochemical performance of batteries. Among the reported cathode candidates, layered oxide materials hold great potential due to their high capacity and a facile synthesis process; however, these materials face some challenges such as low capacity retention and poor air stability. Recently, exploring appropriate methods to strengthen the structural stability and further enhance the energy density of layered oxides has become an emerging research hotspot. In this regard, various strategies, such as element composition and relative content manipulation and microstructure and surface/interface modulation, have been proposed. In this review, typical modification methods for improving the Na-storage performance of layered oxide cathodes are comprehensively summarized. From the perspective of component design, the effects of different doping elements and doping sites on the capacity and cycling life are discussed. In addition, the basic principle of anionic redox reaction to offer extra capacity is elucidated, and the doping strategies for enhancing the anionic redox reversibility are outlined. From the perspective of structure design, the recent progresses on the preparation of composite phase materials and microstructures design are introduced. From the perspective of surface design, the functional mechanism of metal oxides and phosphates as coating layers to improve the structural stability and rate performance is explored. Finally, the challenging issues facing layered sodium oxide cathodes and possible remedies in the future are discussed. We believe that this review will shed light on the development of advanced layered oxide cathode materials for SIBs.
- sodium-ion batteries /
- cathode materials /
- layered oxides /
- modification methods /
- anionic redox

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圖 1 層狀氧化物結構示意圖。（a）P2型；（b）O3型；（c）P3型

Figure 1. Schematic crystal structures of the layered oxides: (a) P2-type; (b) O3-type; (c) P3-type

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圖 2 常用的層狀氧化物儲鈉正極材料改性手段示意圖

Figure 2. Schematic diagram of the commonly used modification methods for layered oxides as Na-storage cathode materials

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圖 3 α-NaFeO₂在高電壓下Fe³⁺的遷移路徑示意圖^[33]

Figure 3. Schematic diagram of Fe³⁺ migration path under high voltage in α-NaFeO₂ ^[33]

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圖 4 P2-Na_2/3Ni_1/3Mn_2/3O₂正極材料的X射線近邊吸收結構譜(XANES)。（a）Mn K邊；（b）Ni K邊^[38]

Figure 4. XANES spectra of the P2-Na_2/3Ni_1/3Mn_2/3O₂ cathode material: (a) Mn K edges; (b) Ni K edges^[38]

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圖 5 P2-Na_x[Fe_1/2Mn_1/2]O₂充電至3.8 V (x = 0.42)和4.2 V (x = 0.13)與初始樣品的同步輻射X射線衍射圖(SXRD, λ = 0.05 nm)對比^[39]

Figure 5. SXRD (λ = 0.05 nm) patterns of the P2-type Na_x[Fe_1/2Mn_1/2]O₂ cathode materials charged to 3.8 V (x = 0.42) and 4.2 V (x = 0.13) in comparison with the as-prepared sample^[39]

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圖 6 隨著Li/TM或O/TM化學計量比增加氧原子配位環境的變化，以及對應氧原子電子結構的變化示意圖^[49]

Figure 6. Local coordination structures around oxygen as a function of the Li/TM or O/TM stoichiometric ratio, along with a schematic diagram of the corresponding electronic structures^[49]

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圖 7 P3-Na_2/3Mg_1/3Mn_2/3O₂ （a）在1.6~4.4 V(vs Na⁺/Na)電壓范圍內第一周和第二周的充放電dQ/dV圖（電流密度為9.7 mA·g^?1）；（b）不同充放電狀態下P3相和O3相的占比分數（采用Rietveld精修方法）^[59]

Figure 7. (a) dQ/dV plots of P3-Na_2/3Mg_1/3Mn_2/3O₂ in the first and second cycles at 9.7 mA·g^?1 from 1.6 V to 4.4 V (vs Na⁺/Na); (b) refined phase fractions of the P3 and O3 phases (using the Rietveld refinement method) at various charge/discharge states of Na_2/3Mg_1/3Mn_2/3O₂^[59]

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圖 8 （a）P2-Na_0.65Li_0.22Mn_0.78O_1.99F_0.01與P2-Na_0.66Li_0.22Mn_0.78O₂的循環性能對比（電流密度為10 mA·g^?1）；（b）P2-NLMOF首次充電過程的原位差示電化學質譜（DEMS）氣體釋放結果^[67]

Figure 8. (a) Comparison of the cycling performance at 10 mA·g^?1 between P2-Na_0.65Li_0.22Mn_0.78O_1.99F_0.01 and P2-Na_0.66Li_0.22Mn_0.78O₂; (b) operando DEMS results of gas evolution during the first charge process of P2-NLMOF^[67]

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圖 9 O3/O′3-P2材料的電子探針X射線微區分析（EPMA）線性掃描（插圖:橫截面掃描電鏡圖像）^[70]

Figure 9. EPMA line scan of the O3/O′3-P2 material (Inset: cross-sectional scanning electron microscopy image)^[70]

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圖 10 充電狀態下在具有（a）蜂窩狀，（b）帶狀，（c）網狀超結構的TM層中形成O₂分子（橙色橢圓形）時面內Mn³⁺遷移路徑（箭頭所示），□代表過渡金屬層的空位^[73]

Figure 10. In-plane Mn³⁺ migration paths (shown by the arrow) in the (a) honeycomb, (b) ribbon, and (c) mesh superstructures in TM layers when O₂ molecules (orange ellipse) are formed during charging, □ represents the vacancies in the TM layer ^[73]

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圖 11 利用預嵌鈉策略在NaFe_0.5Ni_0.5O₂ (NFNO)表面構筑人工電極?電解質界面層(ACEI)的原理示意圖^[82]

Figure 11. Schematic illustration of the preparation of ACEI on the NaFe_0.5Ni_0.5O₂ (NFNO) cathode through a presodiation strategy^[82]

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