镁掺杂协同氧化铝包覆优化锂离子电池高镍正极材料

doi:10.19799/j.cnki.2095-4239.2022.0632

储能科学与技术 ›› 2023, Vol. 12 ›› Issue (2): 339-348.doi: 10.19799/j.cnki.2095-4239.2022.0632

镁掺杂协同氧化铝包覆优化锂离子电池高镍正极材料

张德柳¹(), 张言¹, 王海¹^,², 王佳东², 高宣雯¹(), 刘朝孟¹, 杨东润¹, 骆文彬¹

^1.东北大学冶金学院，辽宁沈阳 110167
^2.广西银亿新材料有限公司，广西玉林 537000

收稿日期:2022-10-28 修回日期:2022-11-25 出版日期:2023-02-05 发布日期:2023-02-24
通讯作者: 高宣雯 E-mail:2071645@stu.neu.edu.cn;gaoxuanwen@ mail.neu.edu.cn
作者简介:张德柳（1998—），男，硕士研究生，研究方向为高镍三元正极材料，E-mail：2071645@stu.neu.edu.cn；
基金资助:
“兴辽英才”青年拔尖项目(XLYC2007155);中央高校基本科研业务费项目(N2025018);东北大学博士后基金项目(01270012810287)

Optimization of high nickel cathode materials for lithium ion batteries by magnesium doped heterogeneous aluminum oxide coating

Deliu ZHANG¹(), Yan ZHANG¹, Hai WANG¹^,², Jiadong WANG², Xuanwen GAO¹(), Chaomeng LIU¹, Dongrun YANG¹, Wenbin LUO¹

^1.School of Metallurgy, Northeastern University, Shenyang 110167, Liaoning, China
^2.Guangxi Yinyi Advanced Material Company Limited, Yulin 537000, Guangxi, China

Received:2022-10-28 Revised:2022-11-25 Online:2023-02-05 Published:2023-02-24
Contact: Xuanwen GAO E-mail:2071645@stu.neu.edu.cn;gaoxuanwen@ mail.neu.edu.cn

摘要/Abstract

摘要：

锂离子电池高镍LiNi _x Co _y Mn_1-_x_-_y O₂(NCM， x≥0.6)正极材料因具有较高的能量密度和低成本等优势在电池领域备受关注，然而随着镍含量的升高，材料锂镍混排严重且热稳定性下降，导致高镍三元材料的循环稳定性和安全性恶化。本研究针对高镍三元材料阳离子无序排列严重和循环稳定性差的问题，通过共沉淀法在前驱体合成过程中将Mg掺杂进入晶体，得到LiNi_0.8Co_0.1Mn_0.09Mg_0.01O₂(Mg1.0)活性材料，进一步利用液相法在材料表面包覆Al₂O₃，成功制备Al₂O₃涂覆的LiNi_0.8Co_0.1Mn_0.09Mg_0.01O₂复合材料(Mg1.0@Al)。X射线衍射(XRD)结果表明，Mg掺杂能够有效扩大材料层间距，抑制阳离子混排；扫描电子显微镜(SEM)结合透射电子显微镜(TEM)结果表明，改性未对NCM811材料整体形貌造成影响，同时能够明显地观察到通过液相法在材料表面包覆的Al₂O₃涂层。电化学测试结果表明，镁铝协同改性可以稳定NCM811材料结构，减少阴极的界面极化，遏制材料与电解液发生副反应，使得材料表现出优越的电化学性能。Mg1.0@Al在1 C循环100次后表现出稳定的放电电压(ΔV=5.2 mV)、较低的电荷转移阻抗(R_ct=51.66 Ω)和卓越的锂离子扩散系数(D_Li=4.05×10^-14 cm²/s)。同时，Mg1.0@Al材料在2.8～4.3 V电压范围下，展现出卓越的循环性能和倍率性能：1 C下循环100次和400次后仍有188.58 mAh/g和147.47 mAh/g的放电比容量，容量保持率分别为95.18%和74.54%；5 C大倍率电流下，放电比容量高达146.3 mAh/g。

关键词: 锂离子电池, 共沉淀, 掺杂包覆, 镁铝协同作用, 阳离子混排, 高镍正极材料

Abstract:

LiNi _x Co _y Mn_1-_x_-_y O₂(NCM, x≥0.6) cathode materials have piqued much interest in Lithium-ion battery because of their high energy density and low-cost. However, the lithium-nickel cations mixed arrangement became serious, and thermal stability decreases as nickel content increases, resulting in deterioration of cycling stability and safety concerns. This paper successfully doped the Mg into NCM using co-precipitation method, followed by Al₂O₃ coating. The as-prepared LiNi_0.8Co_0.1Mn_0.09Mg_0.01O₂@Al₂O₃ (Mg1.0@Al) X-ray diffraction, scanning electron microscopy, and transmission electron microscopy results show that Mg doping can effectively expand the spacing in the crystalline as well as buffer cation mixing. Meanwhile, the Al₂O₃ coating protects the crystals from the cathode-electrolyte side reaction. The electrochemical measurements revealed that the synergistic effects of Mg doping and Al₂O₃ coating can help to stabilize the crystal structure and reduce interfacial polarization. The Mg1.0@Al demonstrated stable discharge voltage (ΔV=5.2 mV), low charge transfer impedance (R_ct=51.66 Ω) and excellent lithium-ion diffusion coefficient (D_Li=4.05×10^-14 cm²/s) after 100 cycles at 1 C. At the voltage range of 2.8—4.3 V, the discharge specific capacity of Mg1.0@Al cathode remains 188.58 mAh/g after 100 cycles and 147.47 mAh/g after 400 cycles, with capacity retention rates of 95.18% and 74.54%, respectively. When changed at 5 C, the discharge specific capacity increased to 146.3 mAh/g.

Key words: lithium-ion battery, co-precipitation, doping coating, synergistic effect of magnesium and aluminum, cation mixing, high nickel cathode material

中图分类号:

TM 911.11

张德柳, 张言, 王海, 王佳东, 高宣雯, 刘朝孟, 杨东润, 骆文彬. 镁掺杂协同氧化铝包覆优化锂离子电池高镍正极材料[J]. 储能科学与技术, 2023, 12(2): 339-348.

Deliu ZHANG, Yan ZHANG, Hai WANG, Jiadong WANG, Xuanwen GAO, Chaomeng LIU, Dongrun YANG, Wenbin LUO. Optimization of high nickel cathode materials for lithium ion batteries by magnesium doped heterogeneous aluminum oxide coating[J]. Energy Storage Science and Technology, 2023, 12(2): 339-348.

图/表 6

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样品	R_s/Ω	R_ct/Ω	σ	D_Li/(cm²/s)
Mg0	8.55	113.70	2.70×10²	5.62×10^-15
Mg1.0	16.55	66.37	1.29×10²	2.46×10^-14
Mg1.0@Al	10.00	51.66	1.01×10²	4.05×10^-14

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镁掺杂协同氧化铝包覆优化锂离子电池高镍正极材料

Optimization of high nickel cathode materials for lithium ion batteries by magnesium doped heterogeneous aluminum oxide coating

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