钠离子电池P2相镍锰基层状氧化物正极材料的研究进展

姜娜; 孙珞然; 王慧丽; 伍忠汉; 焦培鑫; 张凯

doi:10.13374/j.issn2095-9389.2022.08.22.003

钠离子电池P2相镍锰基层状氧化物正极材料的研究进展

doi: 10.13374/j.issn2095-9389.2022.08.22.003

姜娜^{1, 2},
孙珞然^{1, 2},
王慧丽^{1, 2},
伍忠汉^{1, 2},
焦培鑫^{1, 2},
张凯^{1, 2, ,}

1.
南开大学化学学院先进能源材料化学教育部重点实验室，天津 300071
2.
物质绿色创造与制造海河实验室，天津 300192

基金项目: 国家自然科学基金资助项目（22005155，52072186）；中国科协青年人才托举工程资助项目（2019QNRC001）；南开大学中央高校基本科研业务费资助专项（63223015）；天津市物质绿色创造与制造海河实验室资助项目（ZYTS202104）

详细信息

通讯作者:
E-mail: zhangkai_nk@nankai.edu.cn

中图分类号: TG142.71
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出版历程
- 收稿日期: 2022-08-22
- 网络出版日期: 2022-09-26

Recent advances in P2-type Ni–Mn-based layered oxide cathodes for sodium-ion batteries

JIANG Na^{1, 2},
SUN Luo-ran^{1, 2},
WANG Hui-li^{1, 2},
WU Zhong-han^{1, 2},
JIAO Pei-xin^{1, 2},
ZHANG Kai^{1, 2
, ,}

1.
Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), College of Chemistry, Nankai University, Tianjin 300071, China
2.
Haihe Laboratory of Sustainable Chemical Transformations, Tianjin 300192, China

More Information

Corresponding author: E-mail: zhangkai_nk@nankai.edu.cn

摘要

摘要: P2型Na_0.67[Ni, Mn]O₂材料由于较高的比容量、工作电压以及较好的空气稳定性成为最具前景的钠离子电池正极材料之一。然而，高压相变、Na⁺/空位有序排布以及由Mn³⁺引起的Jahn–Teller扭曲导致该类材料充放电过程中面临结构失稳以及性能衰减的挑战。本综述从P2型Na_0.67[Ni, Mn]O₂材料的失效机制出发，系统阐述了该类材料的最新进展。最后，对其未来的发展方向进行了展望。本文将为P2-type Na_0.67[Ni, Mn]O₂材料的研发与商业化提供借鉴。
- 钠离子电池 /
- 正极材料 /
- 镍锰基层状氧化物 /
- 性能衰退机制 /
- 离子掺杂 /
- 表面修饰 /
- P2/O3双相结构
Abstract: As concerns over environmental contamination and rapid consumption of fossil fuels continue to grow, it is important for energy storage technology to reduce the intermittency of clean and renewable energy sources. So far, lithium-ion batteries (LIBs), commercialized by SONY corporation in 1991, have been the most widely used rechargeable batteries for various energy storage devices. Due to the ever-increasing demand for lithium employment in mobile electronic devices and electric vehicles (EVs), the price of Li resources is rising year by year. It is well known that worthwhile lithium resources are only found in a few countries (mainly in South America). Recently, sodium-ion batteries (SIBs) have been regarded as promising alternatives to LIBs for future large-scale energy storage systems (ESSs) owing to their low cost, abundant reservoirs of Na resources and similar characteristics to LIBs. Developing high-performance cathode materials is crucial to realize the commercialization of the SIB technology. Sodium transition metal oxides (Na_xTMO₂), especially for Ni–Mn-based compounds, have received significant attention thanks to their high specific capacity and operating voltage. Normally, layered Na_xTMO₂ materials have two types of crystal structures: P2 and O3, according to the surrounding Na environment and the number of unique oxygen layers occupied within the lattice. Compared with the O3 phase, the P2-type structure has open diffusion channels for the transport of Na⁺ and relatively rare phase transitions, which make P2-type Na_0.67[Ni, Mn]O₂ (NNMO) one of the most promising cathodes for SIBs. However, NNMO materials generally suffer from irreversible P2–O2 phase transformations, Na⁺/vacancy ordering transitions and Jahn–Teller distortion of Mn^(III)O₆ octahedra, leading to structural deterioration and performance degradation during the charge and discharge processes. In detail, the P2–O2 phase transition inevitably causes significant lattice volume change (~20%) and even the formation of cracks, resulting in the stripping of active substances from the collector and serious capacity decay during cycling. The Na⁺/vacancy ordering in NNMO causes the multi-step two-phase reactions, which may increase the activation energy barrier for Na⁺ hops between adjacent prismatic sites, consequently hindering Na⁺ diffusion. Additionally, the lattice distortion and P2-P’2 phase transition induced by the Jahn–Teller effect also impede Na⁺ migration, leading to the sluggish kinetics of Na⁺ (de)intercalation. In this review, the recent progress on NNMO cathodes is summarized, including ion-doping, surface modification and composite structure. The comprehensive and integrated explanation of the structure–function–performance relationship of these optimized cathodes is further presented. Moreover, the existing challenges of NNMO and possible remedies are also discussed. It is expected that this review can provide new insights into the commercialization of NNMO for SIBs.
- sodium-ion batteries /
- cathode materials /
- Ni–Mn based layered oxides /
- performance degradation mechanism /
- ion-doping /
- surface modification /
- P2/O3 mixture

HTML全文

图 1 (a) P2相晶体结构示意图; (b) O3相晶体结构示意图 (c) P2-Na_2/3Mn_2/3Ni_1/3O₂材料首周充放电曲线^[9]

Figure 1. (a) Schematic of P2 phase crystal structure; (b) schematic of O3 phase crystal structure; (c) initial charge/discharge curve of P2-Na_2/3Mn_2/3Ni_1/3O₂^[9]

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图 2 (a) 总荧光产额(TFY)模式下Ni-L3边以及拟合曲线; (b) P2-Na_2/3Mn_2/3Ni_1/3O₂材料的非弹性散射共振光谱(mRIXS)图像(关键的氧的氧化还原特征由红色箭头指出)^[17]; (c)通过对(b)中的两条虚线之间的区域进行积分提取出的非弹性散射共振光谱-超特定荧光产率(mRIXS-sPFY)光谱^[17]; (d) mRIXS-sPFY光谱531 eV处峰面积^[17]; (e) 通过对Ni、O氧化还原以及不可逆反应独立量化来解析总电化学容量^[17]; (f) P2-Na_2/3Mn_2/3Ni_1/3O₂电极的PDOS图^[9]

Figure 2. (a) Ni-L3 edge TFY (solid) and fitted curves^[17]; (b) corresponding mRIXS images of Na_2/3Ni_1/3Mn_2/3O₂ electrode, the key oxygen redox features are indicated by the red arrows^[17]; (c) mRIXS-sPEY spectra extracted from mRIXS by integrating the characteristic 523.7 eV emission energy range, as indicated by the two horizontal dashed lines in Fig.2 (b)^[17]; (d) mRIXS-sPFY 531 eV peak areas^[17]; (e) decipher the total electrochemical capacity by independent quantifications of Ni, Mn and O redox^[17]; (f) PDOS of Na_2/3Ni_1/3Mn_2/3O₂ electrode^[9]

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图 3 (a) P2相高压相变示意图^[18]; (b)Na_2/3Mn_2/3Ni_1/3O₂材料首圈充放电过程中的晶体结构演变^[19]; (c) Na_2/3Mn_2/3Ni_1/3O₂材料不同电压区间内循环50周后SEM图（从左至右依次为原始样品、2～3.8 V、2.0～4.1 V、2.0～4.25 V、2.0～4.5 V）^[20]

Figure 3. (a) Schematic of P2 phase in the high voltage region;^[18] (b) Na_2/3Mn_2/3Ni_1/3O₂ phase transition in the initial charge/discharge process^[19]; (c) SEM images of Na_2/3Mn_2/3Ni_1/3O₂ electrode after 50 cycles in different voltage ranges (From the left to right: pristine sample, 2.0–3.8 V, 2.0–4.1 V, 2.0–4.25 V, 2.0–4.5 V)^[20]

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图 4 Na_x[Mn_2/3Ni_1/3]O₂材料的面内Na⁺有序排布示意图. (a) x=2/3; (b) x=1/2; (c) x=1/3 (绿色球为Na_e位点;粉色球为Na_f位点)^[21]

Figure 4. In-plane Na-ions orderings of Na_x[Mn_2/3 Ni_1/3]O₂: (a) x=2/3; (b) x=1/2; (c) x=1/3 (green balls: Na-ions on Na_e sites; pink balls: Na-ions on Na_f sites)^[21]

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图 5 (a) Mn³⁺的八面体构型示意图; (b) Mn³⁺的Jahn–Teller扭曲示意图^[23]; (c) Na_0.62Ni_1/4Mn_3/4O₂材料在1.5~4.5 V电压区间内的原位XRD图谱^[24]

Figure 5. (a) Schematic of Mn³⁺ octahedral configuration; (b) schematic of Jahn–Teller distortion for Mn^3+[23]; (c) in-situ XRD patterns of Na_0.62Ni_1/4Mn_3/4O₂ electrode during the charge/discharge processes in the voltage range of 1.5–4.5 V^[24]

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图 6 (a) Mg²⁺进入Na_0.70Ni_0.40Mn_0.60O₂材料AM层起到支柱作用示意图^[29]; (b) P2-Na_2/3Ni_1/3Mn_2/3O₂和P2-Na_2/3Ni_1/3Mn_1/3Ti_1/3O₂材料中Na_e和Na_f的能量差计算结果^[22]; (c) P2相结构中Li⁺可以在TM层与AM层之间可逆迁移示意图; (d) Na_0.66I_yNi_zMn_1–y–zO₂ (0.60 ≤ x ≤ 0.80, 0 ≤ y ≤ 0.17, 0.20 ≤ z ≤0.33)材料的比容量与循环稳定性性能对比^[32]

Figure 6. (a) Schematic diagram of the pillar effect of Mg²⁺ for Na_0.70Ni_0.4Mn_0.60O₂ electrode^[29]; (b) calculated energy difference between the Na_e and Na_f sites for P2-Na_2/3Ni_1/3Mn_2/3O₂ and P2-Na_2/3Ni_1/3Mn_1/3Ti_1/3O₂ eletrodes^[22]; (c) reversible migration of Li⁺ between the TM and AM layers in P2 phase; (d) comparison of capacity and cycle stability of Na_0.66I_yNi_zMn_1–y–zO₂ (0.60 ≤ x ≤ 0.80, 0 ≤ y ≤ 0.17, 0.20 ≤ z ≤0.33) substituted with different inert cations^[32]

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图 7 (a) Cu²⁺掺杂作用机制^[37]; (b) Co³⁺离子掺杂作用机制^[39]; (c) Na⁺在Na_2/3Ni_1/3Mn_2/3O₂、Na_2/3Mn_1/3Co_2/3O₂以及Na_2/3Mn_1/2Ni_1/6Co_1/3O₂材料内的分布状态^[40]

Figure 7. (a) Mechanisms of Cu-doping^[37]; (b) mechanisms of Co-doping^[39]; (c) distribution of Na⁺ in Na_2/3Ni_1/3Mn_2/3O₂, Na_2/3Mn_1/3Co_2/3O₂, and Na_2/3Mn_1/2Ni_1/6Co_1/3O₂ electrodes^[40]

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图 8 (a) Na_2/3Ni_1/6Mn_2/3Cu_1/9Mg_1/18O₂在5C电流密度下的长循环稳定性^[41]; (b) [Na_0.67Zn_0.05]Ni_0.18Cu_0.1Mn_0.67O₂材料的在[–220]方向的ABF-STEM图; (c) [Na_0.67Zn_0.05]Ni_0.18Cu_0.1Mn_0.67O₂材料在10 C的电流密度下的长循环稳定性^[42]; (d) P2-Na_0.75Ca_0.04[Li_0.1Ni_0.2Mn_0.67]O₂材料在2.0～4.3 V的电压区间内不同循环圈数的放电dQ/dV曲线; (e) P2-Na_0.75Ca_0.04[Li_0.1Ni_0.2Mn_0.67]O₂材料在2.0～4.0 V的电压区间内不同循环圈数的放电dQ/dV曲线; (f) P2-Na_0.75Ca_0.04[Li_0.1Ni_0.2Mn_0.67]O₂材料在2.0～4.3 V的电压区间内循环1周、10周、20周、30周以及50周后Mn的K边吸收光谱^[43]

Figure 8. (a) Long-term cycling stability of Na_2/3Ni_1/6Mn_2/3Cu_1/9Mg_1/18O₂ electrode at 5C^[41]; (b) ABF-STEM image of [Na_0.67Zn_0.05]Ni_0.18Cu_0.1Mn_0.67O₂ electrode viewed from [–220] axis; (c) long-term cycling stability of [Na_0.67Zn_0.05]Ni_0.18Cu_0.1Mn_0.67O₂ electrode at 10C^[42]; (d) discharge dQ/dV curves within 2.0–4.3 V for P2-Na_0.75Ca_0.04[Li_0.1Ni_0.2Mn_0.67]O₂ electrode; (e) discharge dQ/dV curves within 2.0–4.0 V for P2-Na_0.75Ca_0.04[Li_0.1Ni_0.2Mn_0.67]O₂ electrode; (f) Mn K-edge XAS results collected at the 2 V discharged state after the 1st, 10th, 20th, 30th, and 50th cycles within 2.0–4.3 V for P2-Na_0.75Ca_0.04[Li_0.1Ni_0.2Mn_0.67]O₂ electrode^[43]

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图 9 (a)多组分掺杂电极作用机制;(b)CuMgTi-571在10C的电流密度下的长循环稳定性^[44]

Figure 9. (a) Functional mechanism of multicomponent-doped electrode; (b) long-term cycling stability of CuMgTi-571 at 10C^[44]

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图 10 (a) Ca²⁺和空位掺杂的Na_0.66Ni_0.33Mn_0.67O₂电极晶体结构示意图; (b) P2-Na_0.76Ca_0.05[Ni_0.23□_0.08Mn_0.69]O₂正极在不同电流密度下的循环稳定性^[46]

Figure 10. (a) Schematic of the crystal structure of Ca²⁺ and vacancy co-doped Na_0.66Ni_0.33Mn_0.67O₂ electrode; (b) cycling stability of P2-Na_0.76Ca_0.05[Ni_0.23□_0.08Mn_0.69]O₂ cathode at different current densities^[46]

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图 11 (a)采用熔体–浸渍工艺在Na_2/3[Ni_1/3Mn_2/3]O₂材料表面构筑NaPO₃包覆层示意图^[49]; (b) Na_0.66Ni_0.26Zn_0.07Mn_0.67O₂(NNZM)和Na_0.66Ni_0.26Zn_0.07Mn_0.67O₂/0.06ZnO (NNZM/0.06ZnO)电极表面CEI膜对比示意图;(c)NNZM和NNZM/0.06ZnO在100 mA·g^–1的电流密度下的循环性能^[52]

Figure 11. (a) Schematic of melt–impregnation of NaPO₃ coating on Na_2/3[Ni_1/3Mn_2/3]O₂^[49]; (b) schematic of the CEI films formed on the Na_0.66Ni_0.26Zn_0.07Mn_0.67O₂(NNZM) and Na_0.66Ni_0.26Zn_0.07Mn_0.67O₂/0.06ZnO (NNZM/0.06ZnO) particles; (c) cycling performance of NNZM and NNZM/0.06ZnO at 100 mA·g^–1[52]

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图 12 (a) P2-Na_2/3Ni_1/3Mn_0.57Ti_0.1O₂、(b) O3-NaNi_1/3Fe_1/3Mn_1/3O₂以及(c) P2/O3-Na_0.754Ni_0.326Mn_0.501Fe_0.098Ti_0.07O₂材料在钠离子脱嵌过程中的晶体结构变化示意图^[53]; (d) P2-Na_0.7Ni_0.2Cu_0.1Fe_0.2Mn_0.5O_2–δ,O3-Na_0.8Ni_0.2Cu_0.1Fe_0.2Mn_0.5O_2–δ以及P2/O3-Na_0.7Ni_0.2Cu_0.1Fe_0.2Mn_0.5O_2–δ电极在2.0～4.05 V电压区间内的倍率性能; (e) P2-Na_0.7Ni_0.2Cu_0.1Fe_0.2Mn_0.5O_2–δ,O3-Na_0.8Ni_0.2Cu_0.1Fe_0.2Mn_0.5O_2–δ以及P2/O3-Na_0.7Ni_0.2Cu_0.1Fe_0.2Mn_0.5O_2–δ电极在2.0～4.05 V电压区间内及240 mA·g^–1下的循环稳定性^[54]

Figure 12. Schematic of structural changes of (a) P2-Na_2/3Ni_1/3Mn_0.57Ti_0.1O₂, (b) O3-NaNi_1/3Fe_1/3Mn_1/3O₂ and (c) P2/O3-Na_0.754Ni_0.326Mn_0.501Fe_0.098Ti_0.07O₂ during Na (de)sodiation^[53]; (d) rate capabilities of P2-Na_0.7Ni_0.2Cu_0.1Fe_0.2Mn_0.5O_2–δ, O3-Na_0.8Ni_0.2Cu_0.1Fe_0.2Mn_0.5O_2–δ and P2/O3-Na_0.7Ni_0.2Cu_0.1Fe_0.2Mn_0.5O_2–δ electrode tested within 2.0–4.05 V, (e) cycling performances of P2-Na_0.7Ni_0.2Cu_0.1Fe_0.2Mn_0.5O_2–δ, O3-Na_0.8Ni_0.2Cu_0.1Fe_0.2Mn_0.5O_2–δ and P2/O3-Na_0.7Ni_0.2Cu_0.1Fe_0.2Mn_0.5O_2–δ electrode tested at a rate of 240 mA·g^–1 within 2.0–4.05 V^[54]

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表 1 不同元素掺杂对P2-Na_0.67[Ni, Mn]O₂材料性能提升对比

Table 1. Comparison of performance of P2-Na_0.67[Ni, Mn]O₂ materials improved by doping different elements

Materials	Initial capacity/(mA·h·g^–1)	Rate performance/ (mA·h·g^–1)	Cycle performance/(mA·h·g^–1)	References
Na_2/3Ni_1/3Mn_2/3O₂	167 (12 mA·g^–1) (2.0–4.4 V)	30 (2C)	167 (12 mA·g^–1) 30% (100 cycles)	7
Na_0.62Ni_1/4Mn_3/4O₂	185 (15 mA·g^–1) (1.5–4.3 V)	120(500 mA·g^–1)	185 (15 mA·g^–1) 84% (50 cycles)	24
Na_0.67Mn_0.67Ni_0.28Mg_0.05O₂	123 (0.1C) (2.5–4.35 V)	—	123 (0.1C) 85% (50 cycles)	27
Na_0.67Mg_0.05[Mn_0.60Ni_0.20Mg_0.15]O₂	130 (0.2C) (1.5–4.2 V) 78 (1C) (2.5–4.2 V)	57 (25C)	78 (1C) 79% (1000 cycles) 130 (0.2C) 73% (180 cycles)	29
Na_0.67Ni_0.23Mn_0.67Mg_0.1O₂	117 (0.1C) (2.5–4.4 V)	60 (5C)	117 (0.1C) 95.3%(50 cycles) 70 (5C) 90.9% (1000 cycles)	30
Na_2/3Ni_1/3Mn_1/2Ti_1/6O₂	127 (12.1 mA·g^–1) (2.5–4.5 V)	90 (2C)	127 (12.1 mA·g^–1 ) 90.5% (20 cycles)	31
Na_2/3Ni_1/3Mn_1/3Ti_1/3O₂	90 (0.1C) (2.5–4.15 V)	70 (20C)	87 (1 C) 83.9% (500 cycles)	22
Na_0.80Li_0.12Ni_0.22Mn_0.66O₂	118 (0.1C) (2.0–4.4 V)	70.8 (5C)	118 (0.1C) 91% (50 cycles)	33
Na_0.67Mn_0.6Ni_0.2Li_0.2O₂	100 (0.1C) (2.0–4.6 V)	70 (2C)	110 (0.1C) 102% (100 cycles)	34
Na0.66Ni0.26Mn0.67Zn_0.07O2	127 (12 mA·g^–1) (2.2–4.3 V)	—	127 (12 mA·g^–1) 93.1% (10 cycles)	13
Na_0.6Ni_0.22Al_0.11Mn_0.66O₂	252 (20 mA·g^–1)(1.5–4.6 V)	140 (5 C)	252 (20 mA·g^–1) 80% (50 cycles)	32
Na_0.67Ni_0.1Cu_0.2Mn_0.7O₂	120 (0.1C) (2.0–4.5 V)	55 (20C)	120 (0.1C) 67% (100 cycles)	37
Na_0.7Mn_0.7Ni_0.2Co_0.1O₂	160 (50 mA·g^–1) (1.5–4.0 V)	75 (500 mA·g^–1)	100 (1 A·g^–1) 87% (300 cycles)	39
Na_2/3Ni_1/6Mn_2/3Cu_1/9Mg_1/18O₂	87.9 (0.5C) (2.5–4.15 V)	60 (30C)	80 (5C) 81.4% (500 cycles)	41
[Na_0.67Zn_0.05]Ni_0.18Cu_0.1Mn_0.67O₂	100 (0.1C) (2.5–4.4 V)	60 (10C)	60 (10C) 80.6% (2000 cycles)	42
Na_0.75Ca_0.04[Li_0.1Ni_0.2Mn_0.67]O₂	130 (0.1 V) (2.0–4.3 V)	68.8 (20C)	80 (10C) 87.7% (500 cycles)	43
Na_0.62Mn_0.67Ni_0.23Cu_0.05Mg_0.03Ti_0.06O₂	148.2 (0.1C) (2.0–4.3 V)	80 (10C)	120 (1C) 87% (500 cycles) 78.6 (10C) 75% (2000 cycles)	44
Na_0.7Li_0.03Mg_0.03Ni_0.27Mn_0.6Ti_0.07O₂	135 (0.1C) (2.2–4.4 V)	110 (4C)	116.8 (2C) 82% (200 cycles)	45
Na_0.76Ca_0.05[Ni_0.23□_0.08Mn_0.69]O₂	153.9 (0.1C) (2.0–4.3 V)	74.6 (20C)	95 (5C) 75.3% (200 cycles)	46

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参考文献(54)

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