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Corresponding Author

Ying-Qiang Wu(yqwu02@tsinghua.edu.cn);
Xiang-Ming He(hexm@mail.tsinghua.edu.cn)

Abstract

Lithium layered oxide LiNi0.6Co0.2Mn0.2O2 (NCM622) is one of the most promising cathode materials in high-energy lithium-ion batteries for electric vehicles. However, one drawback for NCM622 is that its initial coulombic efficiency (ICE) is only about 87%, which is at least 6% lower than that of LiCoO2 or LiFePO4. In this work, we investigated the effects of surface chemical residues (e.g., LiOH and Li2CO3) and Li/Ni cation disorder resulted during the sintering on the ICE. We found that the ICE of the as-prepared samples could be boosted from 80.80% to 86.68% as the sintering temperatures were increased from 825 to 900 oC. The corresponding Li/Ni cation disorder and surface chemical residues were also reduced with the increasing sintering temperatures. Furthermore, the ICE of the sample sintered at 825 oC could be enhanced by 3.57% after washing with HNO3 solution to remove the surface residues despite the Li/Ni cation disorder being increased. These results demonstrate that minimizing the amount of surface residuals and the degree of Li/Ni cation disorder through an appropriate sintering process and post-treatment technology is critical to achieve a high ICE and improve the electrochemical performances of NCM622.

Graphical Abstract

Keywords

lithium layered oxide cathode, initial coulombic efficiency, surface chemical residues, Li/Ni cation disorder

Publication Date

2022-11-28

Online Available Date

2022-10-31

Revised Date

2022-09-27

Received Date

2022-08-21

References

[1] Wu Y Q, Xie L Q, Ming H, Guo Y J, Hwang J Y, Wang W X, He X M, Wang L M, Alshareef H N, Sun Y K, Ming J. An empirical model for the design of batteries with high energy density[J]. ACS Energy Lett., 2020, 5(3): 807-816.

[2] Zhang B, Wang L, Zhang H, Xu H, He X M. Revelation of the transition-metal doping mechanism in lithium manganese phosphate for high performance of lithium-ion batteries[J]. Battery Energy, 2022, 1(4): 20220020.

[3] Xue H J, Wu Y Q, Zou Y G, Shen Y B, Liu G, Li Q, Yin D M, Wang L M, Ming J. Unraveling metal oxide role in exfoliating graphite: new strategy to construct high-performance graphene-modified SiOx-based anode for lithium-ion batteries[J]. Adv. Funct. Mater., 2020, 30(21): 1910657.

[4] Wu Y Q, Ming H, Li M L, Zhang J L, Wahyudi W, Xie L Q, He X M, Wang J, Wu Y P, Ming J. New organic complex for lithium layered oxide modification: ultrathin coating, high-voltage, and safety performances[J]. ACS Energy Lett., 2019, 4(3): 656-665.

[5] Zhang B, He Y F, Gao H Q, Wang X D, Liu J L, Xu H, Wang L, He X M. Unraveling the doping mechanisms in lithium iron phosphate[J]. Energy Mater., 2022, 2: 200013.

[6] Li W D, Dolocan A, Oh P, Celio H, Park S, Cho J, Manthiram A. Dynamic behaviour of interphases and its implication on high-energy-density cathode materials in lithium-ion batteries[J]. Nat. Commun., 2017, 8: 14589.
doi: 10.1038/ncomms14589 pmid: 28443608

[7] Ryu H H, Park K J, Yoon C S, Sun Y K. Capacity fading of Ni-rich Li[NixCoyMn1-x-y]O2 (0.6≤ x ≤ 0.95) cathodes for high-energy-density lithium-Iion batteries: bulk or surface degradation?[J]. Chem. Mater., 2018, 30(3): 1155-1163.

[8] Wu Y Q, Xie L Q, He X M, Zhuo L H, Wang L M, Ming J. Electrochemical activation, voltage decay and hysteresis of Li-rich layered cathode probed by various cobalt content[J]. Electrochim. Acta, 2018, 265: 115-120.

[9] Fan L, Wei S Y, Li S Y, Li Q, Lu Y Y. Recent progress of the solid-state electrolytes for high-energy metal-based batteries[J]. Adv. Energy Mater., 2018, 8(11): 1702657.

[10] Wu Y Q, Ming J, Zhuo L H, Yu Y C, Zhao F Y. Simultaneous surface coating and chemical activation of the Li-rich solid solution lithium rechargeable cathode and its improved performance[J]. Electrochim. Acta, 2013, 113: 54-62.

[11] Jun D W, Yoon C S, Kim U H, Sun Y K. High-energy density core-shell structured Li[Ni0.95Co0.025Mn0.025]O2 cathode for lithium-ion batteries[J]. Chem. Mater., 2017, 29(12): 5048-5052.

[12] Lee W, Muhammad S, Kim T, Kim H, Lee E, Jeong M, Son S, Ryou J H, Yoon W S. New insight into Ni-rich layered structure for next-generation Li rechargeable batteries[J]. Adv. Energy Mater., 2018, 8(4): 1701788.

[13] Liu W, Li X F, Xiong D B, Hao Y C, Li J W, Kou H R, Yan B, Li D J, Lu S G, Koo A, Adair K, Sun X L. Significantly improving cycling performance of cathodes in lithium ion batteries: the effect of Al2O3 and LiAlO2 coatings on LiNi0.6Co0.2Mn0.2O2[J]. Nano Energy, 2018, 44: 111-120.

[14] Lee S W, Kim M S, Jeong J H, Kim D H, Chung K Y, Roh K C, Kim K B. Li3PO4 surface coating on Ni-rich LiNi0.6Co0.2Mn0.2O2 by a citric acid assisted sol-gel method: improved thermal stability and high-voltage performance[J]. J. Power Sources, 2017, 360: 206-214.

[15] Chen Z Q, Wang J, Huang J X, Fu T, Sun G Y, Lai S B, Zhou R, Li K, Zhao J B. The high-temperature and high-humidity storage behaviors and electrochemical degradation mechanism of LiNi0.6Co0.2Mn0.2O2 cathode material for lithium ion batteries[J]. J. Power Sources, 2017, 363: 168-176.

[16] Liu S Y, Dang Z Y, Liu D, Zhang C C, Huang T, Yu A S. Comparative studies of zirconium doping and coating on LiNi0.6Co0.2Mn0.2O2 cathode material at elevated temperatures[J]. J. Power Sources, 2018, 396: 288-296.

[17] Yuan J, Wen J W, Zhang J B, Chen D M, Zhang D W. Influence of calcination atmosphere on structure and electrochemical behavior of LiNi0.6Co0.2Mn0.2O2 cathode material for lithium-ion batteries[J]. Electrochim. Acta, 2017, 230: 116-122.

[18] Choi J, Manthiram A. Investigation of the irreversible capacity loss in the layered LiNi1/3Mn1/3Co1/3O2 cathodes[J]. Electrochem. Solid-State Lett., 2005, 8(8): C102-C105.

[19] Hu Q, Wu Y Z, Ren D S, Liao J Y, Song Y Z, Liang H M, Wang A P, He Y F, Wang L, Chen Z H, He X M. Revisiting the initial irreversible capacity loss of LiNi0.6Co0.2-Mn0.2O2 cathode material batteries[J]. Energy Stor. Mater., 2022, 50: 373-379.

[20] Hong C Y, Leng Q Y, Zhu J P, Zheng S Y, He H J, Li Y X, Liu R, Wan J J, Yang Y. Revealing the correlation between structural evolution and Li+ diffusion kinetics of nickel-rich cathode materials in Li-ion batteries[J]. J. Mater. Chem. A, 2020, 8(17): 8540-8547.

[21] Zhou H, Xin F X, Pei B, Whittingham M S. What limits the capacity of layered oxide cathodes in lithium batteries?[J]. ACS Energy Lett., 2019, 4(8): 1902-1906.
doi: 10.1021/acsenergylett.9b01236

[22] Zhao E Y, Fang L C, Chen M M, Chen D F, Huang Q Z, Hu Z B, Yan Q B, Wu M M, Xiao X L. New insight into Li/Ni disorder in layered cathode materials for lithium ion batteries: a joint study of neutron diffraction, electrochemical kinetic analysis and first-principles calculations[J]. J. Mater. Chem. A, 2017, 5(4): 1679-1686.

[23] Chen M M, Zhao E Y, Chen D F, Wu M M, Han S B, Huang Q Z, Yang L M, Xiao X L, Hu Z B. Decreasing Li/Ni disorder and improving the electrochemical performances of Ni-rich LiNi0.8Co0.1Mn0.1O2 by Ca doping[J]. Inorg. Chem., 2017, 56(14): 8355-8362.

[24] Kasnatscheew J, Evertz M, Streipert B, Wagner R, Klopsch R, Vortmann B, Hahn H, Nowak S, Amereller M, Gentschev A C, Lamp P, Winter M. The truth about the 1st cycle coulombic efficiency of LiNi1/3Co1/3Mn1/3O2(NCM) cathodes[J]. Phys. Chem. Chem. Phys., 2016, 18(5): 3956-3965.
doi: 10.1039/c5cp07718d pmid: 26771035

[25] Wei H X, Tang L B, Huang Y D, Wang Z Y, Luo Y H, He Z J, Yan C, Mao J, Dai K H, Zheng J C. Comprehensive understanding of Li/Ni intermixing in layered transition metal oxides[J]. Mater. Today, 2021, 51: 365-392.

[26] Huang Z J, Wang Z X, Zheng X B, Guo H J, Li X H, Jing Q, Yang Z H. Structural and electrochemical properties of Mg-doped nickel based cathode materials LiNi0.6Co0.2-Mn0.2-xMgxO2 for lithium ion batteries[J]. RSC Adv., 2015, 5(108): 88773-88779.

[27] Huang Z J, Wang Z X, Jing Q, Guo H J, Li X H, Yang Z H. Investigation on the effect of Na doping on structure and Li-ion kinetics of layered LiNi0.6Co0.2Mn0.2O2 cathode material[J]. Electrochim. Acta, 2016, 192: 120-126.

[28] Yoon C S, Choi M J, Jun D W, Zhang Q, Kaghazchi P, Kim K H, Sun Y K. Cation ordering of Zr-doped LiNiO2 cathode for lithium-ion batteries[J]. Chem. Mater., 2018, 30(5): 1808-1814.

[29] Liu S Y, Chen X, Zhao J Y, Su J M, Zhang C C, Huang T, Wu J H, Yu A S. Uncovering the role of Nb modification in improving the structure stability and electrochemical performance of LiNi0.6Co0.2Mn0.2O2 cathode charged at higher voltage of 4.5 V[J]. J. Power Sources, 2018, 374: 149-157.

[30] Jo J H, Jo C H, Yashiro H, Kim S J, Myung S T. Re-heating effect of Ni-rich cathode material on structure and electrochemical properties[J]. J. Power Sources, 2016, 313: 1-8.

[31] Noh H J, Youn S, Yoon C S, Sun Y K. Comparison of the structural and electrochemical properties of layered Li[NixCoyMnz]O2 (x = 1/3, 0.5, 0.6, 0.7, 0.8 and 0.85) cathode material for lithium-ion batteries[J]. J. Power Sources, 2013, 233: 121-130.

[32] Eom J, Kim M G, Cho J. Storage characteristics of LiNi0.8-Co0.1+xMn0.1-xO2 (x = 0, 0.03, and 0.06) cathode materials for lithium batteries[J]. J. Electrochem. Soc., 2008, 155(3): A239-A245.

[33] Shen Y B, Wu Y Q, Xue H J, Wang S H, Yin D M, Wang L M, Cheng Y. Insight into the coprecipitation-controlled crystallization reaction for preparing lithium-layered oxide cathodes[J]. ACS Appl. Mater. Interfaces, 2021, 13(1): 717-726.

[34] Shaju K M, Rao G V S, Chowdari B V R. Performance of layered Li(Ni1/3Co1/3Mn1/3)O2 as cathode for Li-ion batteries[J]. Electrochim. Acta, 2002, 48(2): 145-151.

[35] Su Y F, Chen G, Chen L, Li W K, Zhang Q Y, Yang Z R, Lu Y, Bao L Y, Tan J, Chen R J, Chen S, Wu F. Exposing the {010} planes by oriented self-assembly with nano-sheets to improve the electrochemical performances of Ni-rich Li[Ni0.8Co0.1Mn0.1]O2 microspheres[J]. ACS Appl. Mater. Interfaces, 2018, 10(7): 6407-6414.

[36] Hua W B, Liu W Y, Chen M Z, Indris S, Zheng Z, Guo X D, Bruns M, Wu T H, Chen Y X, Zhong B H, Chou S L, Kang Y M, Ehrenberg H. Unravelling the growth mechanism of hierarchically structured Ni1/3Co1/3Mn1/3(OH)2 and their application as precursors for high-power cathode materials[J]. Electrochim. Acta, 2017, 232: 123-131.

[37] Matienzo L J, Yin L I, Grim S O, Jr S W E. X-ray photoelectron spectroscopy of nickel compounds[J]. Inorg. Chem., 1973, 12: 2762-2769.

[38] Kim K S, Winograd N. X-ray photoelectron spectroscopic studies of nickel-oxygen surfaces using oxygen and argon ion-bombardment[J]. Surf. Sci., 1974, 43(2): 625-643.

[39] Tan B J, Klabunde K J, Sherwood P M A. XPS studies of solvated metal atom dispersed (SMAD) catalysts. Evidence for layered cobalt-manganese particles on alumina and silica[J]. J. Am. Chem. Soc., 1991, 113: 855-861.

[40] Aoki A. X-ray Photoelectron spectroscopic studies on ZnS: MnF2 Phosphors[J]. Jpn. J. Appl. Phys., 1976, 15: 305-311.

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