現今鋰離子電池發展追求更高的能量密度，相較於目前商業化的正極材料，過量鋰材料Li1.2Ni0.2Mn0.6O2因具備較高的比電容量 ( >250 mAh /g）以及較高的的工作電壓而備受期待。然而其本身的缺陷，例如電容量衰退、電壓衰退、易與電解液發生副反應等因素，阻礙了其商業化的發展性。本研究利用溶膠-凝膠法以一步燒結的方法將高導離度的磷酸鋰材料塗覆於過量鋰Li1.2Ni0.2Mn0.6O2表面；相較於一般的塗覆方法，需先合成過量鋰粉體Li1.2Ni0.2Mn0.6O2，後續再經過不同方法進行塗覆以及燒結，本研究能有效的簡化製程，且同時達到減少與電解液副反應的發生，以及減少循環過程中層狀結構轉變成尖晶石結構，使得材料穩定性提高、電化學性能增強。
本研究將磷酸銨(NH4)2HPO4於溶膠-凝膠法的過程中與過量鋰前驅物同時加入水中，攪拌均勻後經過450度的燒結生成磷酸鋰Li3PO4，再加熱至900度以形成過量鋰Li1.2Ni0.2Mn0.6O2，同時磷酸鋰將包覆於過量鋰表面。實驗結果顯示，塗覆磷酸鋰的粉末於2.5-4.8V區間經過100次循環後，電容量保持率高達89％，同時，減少極化的現象，以及可以從dQ/dV圖發現有效的減緩層狀結構轉變至尖晶石結構的發生，此外於高速率充放電下 (0.5C) 也因磷酸鋰的高導離度擁有更加的表現。後續利用表面分析以及阻抗分析得知經過塗覆後的過量鋰材料有效的減少了與電解液副反應的發生。因此，一步式溶膠-凝膠法確實能將磷酸鋰Li3PO4塗覆於過量鋰Li1.2Ni0.2Mn0.6O2表面，且改善其電容量、電壓衰退並減少與電解液反應等問題，同時還能增加其高速率下的表現。

Nowadays, pursuing batteries with high energy density becomes a trend. Compared to other commercial cathode materials, lithium-rich materials Li1.2Ni0.2Mn0.6O2 has attracted great attention because of their high specific capacity (>250mAh/g) and high working voltage. Nevertheless, their inherent shortcomings, such as voltage fading, capacity degradation, easily reactive with electrolytes, have inhibited their commercial application. In this study, a one-step sol-gel method that can improve the performance of lithium-rich materials with high ionic conductivity material Li3PO4 is introduced. Not like usual coating methods, which synthesize lithium-rich materials first, then coat on it. This study shows an efficiently simplified process that only requires a single-step coating process to reduce the chance of reacting with the electrolyte. Also, the one-step coating process could reduce the phase transformation from the layered to the spinel-like structure. Therefore, structural stability and electrochemical performance are enhanced.
In this work, during the process of applying the sol-gel method, (NH4)2HPO4 is added to the lithium-rich precursor metal acetate with water along with well stirring. Then, the mixture was heated up to 450 degrees to form Li3PO4 first and 900 degrees to synthesize Li3PO4-coated Li1.2Ni0.2Mn0.6O2. According to the experiment result, Li3PO4-coated Li1.2Ni0.2Mn0.6O2 achieved 89% retention after 100 cycles in the potential window from 2.5V to 4.8V at 0.1C. Meanwhile, it could decrease the polarization after cycling and mitigate the phase transformation from the differential capacity (dQ/dV) analysis. On the other hand, it also increased the rate capability under high C-rate attributed to the high ionic conductivity of Li3PO4. Next, by utilizing surface analysis and EIS, it is revealed that the reaction with electrolyte was effectively reduced after coating Li3PO4 on the surface of Lithium-rich materials. In conclusion, the developed one-step sol-gel method can coat Li3PO4 on the surface of Lithium-rich material Li1.2Ni0.2Mn0.6O2 and improve its inherent drawbacks, such as capacity decrease and voltage fading during cycling.

1. T.D. Liberto, May 2020: Global temperatures tie for record hottest. National Oceanic and Atmospheric Administration(NOAA), June 15, 2020.
2. P. Dorin, D. Bureţea, Stud, A. Cormos, and Cormos, HYBRID CAR BATTERY MANAGEMENT. 2021.
3. M.S. WHITTINGHAM, Electrical Energy Storage and Intercalation Chemistry. Science, 11 JUNE 1976.
4. K. Mizushima, P.C. Jones, P.J. Wiseman, and J.B. Goodenough, LixCoO2 (0<x<-1): A new cathode material for batteries of high energy density. Materials Research Bulletin, 1980. 15(6): p. 783-789.
5. 簡說鋰離子電池工作原理. 2017-10-19: 每日頭條.
6. G. Jeong, Y.-U. Kim, H. Kim, Y. Kim, and H.-J. Sohn, Prospective materials and applications for Li secondary batteries. Energy Environ. Sci., 2011. 4: p. 1986-2002.
7. K.M. Abraham, Prospects and Limits of Energy Storage in Batteries. The Journal of Physical Chemistry Letters, 2015. 6(5): p. 830-844.
8. M. Brain, How Lithium-ion Batteries Work. HowStuffWorks.com., 5 April 2021
9. Y. Liang, C.Z. Zhao, H. Yuan, Y. Chen, W. Zhang, J.Q. Huang, D. Yu, Y. Liu, M.M. Titirici, Y.L. Chueh, H. Yu, and Q. Zhang, A review of rechargeable batteries for portable electronic devices. InfoMat, 2019. 1(1): p. 6-32.
10. C.M. Julien, A. Mauger, K. Zaghib, and H. Groult, Comparative Issues of Cathode Materials for Li-Ion Batteries. Inorganics, 2014. 2(1): p. 132-154.
11. T.O.a.Y. Makimura, Layered Lithium Insertion Material of LiCo1/3Ni1/3Mn1/3O2 for Lithium-Ion Batteries. The Chemical Society of Japan, April 27, 2001;.
12. J.M. Tarascon, W.R. McKinnon, F. Coowar, T.N. Bowmer, G. Amatucci, and D. Guyomard, Synthesis Conditions and Oxygen Stoichiometry Effects on Li Insertion into the Spinel LiMn2O4. Journal of The Electrochemical Society, 1994. 141(6): p. 1421-1431.
13. K. Zaghib, A. Mauger, H. Groult, J.B. Goodenough, and C.M. Julien, Advanced Electrodes for High Power Li-ion Batteries. Materials, 2013. 6(3).
14. J. Zheng, S. Myeong, W. Cho, P. Yan, J. Xiao, C. Wang, J. Cho, and J.G. Zhang, Li‐ and Mn‐Rich Cathode Materials: Challenges to Commercialization. Advanced Energy Materials, 2016. 7(6).
15. K. Mizushima, P.C. Jones, P.J. Wiseman, and J.B. Goodenough, LixCoO2 (0<x<1): A new cathode material for batteries of high energy density. Solid State Ionics, 1981. 3-4: p. 171-174.
16. R.J. Gummow and M.M. Thackeray, Lithium-cobalt-nickel-oxide cathode materials prepared at 400б╟C for rechargeable lithium batteries. Solid State Ionics, 1992. 53-56: p. 681-687.
17. E. Rossen, J.N. Reimers, and J.R. Dahn, Synthesis and electrochemistry of spinel LTН-LiCoO2. Solid State Ionics, 1993. 62(1): p. 53-60.
18. G. Hasegawa, N. Kuwata, Y. Tanaka, T. Miyazaki, N. Ishigaki, K. Takada, and J. Kawamura, Tracer diffusion coefficients of Li+ ions in c-axis oriented LixCoO2 thin films measured by secondary ion mass spectrometry. Physical Chemistry Chemical Physics, 2021. 23(3): p. 2438-2448.
19. M.M. Thackeray, W.I.F. David, and J.B. Goodenough, Structural characterization of the lithiated iron oxides LixFe3O4 and LixFe2O3 (0<x<2). Materials Research Bulletin, 1982. 17(6): p. 785-793.
20. M.M. Thackeray, Structural Fatigue in Spinel Electrodes in High Voltage (4.8V) Li/Li xMn2O4Cells. Electrochemical and Solid-State Letters, 1999. 1(1): p. 7.
21. W. Choi and A. Manthiram, Comparison of Metal Ion Dissolutions from Lithium Ion Battery Cathodes. Journal of The Electrochemical Society, 2006. 153: p. A1760-A1764.
22. R.J. Gummow, A. de Kock, and M.M. Thackeray, Improved capacity retention in rechargeable 4 V lithium/lithium-manganese oxide (spinel) cells. Solid State Ionics, 1994. 69(1): p. 59-67.
23. C.M. Julien, A. Mauger, K. Zaghib, and H. Groult, Comparative Issues of Cathode Materials for Li-Ion Batteries. Inorganics, 2014. 2(1).
24. D. Aurbach, M.D. Levi, K. Gamulski, B. Markovsky, G. Salitra, E. Levi, U. Heider, L. Heider, and R. Oesten, Capacity fading of LixMn2O4 spinel electrodes studied by XRD and electroanalytical techniques. Journal of Power Sources, 1999. 81-82: p. 472-479.
25. J.C. Hunter, Preparation of a new crystal form of manganese dioxide: н╩-MnO2. Journal of Solid State Chemistry, 1981. 39(2): p. 142-147.
26. D. Tang, Y. Sun, Z. Yang, L. Ben, L. Gu, and X. Huang, Surface Structure Evolution of LiMn2O4 Cathode Material upon Charge/Discharge. Chemistry of Materials, 2014. 26(11): p. 3535-3543.
27. M. Hosoya, H. Ikuta, and M. Wakihara, Single phase region of cation substituted spinel LiMyMn2-yO4 (M=Cr, Co and Ni) and cathode property for lithium secondary battery. Solid State Ionics, 1998. 111(1): p. 153-159.
28. Y.M. Todorov, Y. Hideshima, H. Noguchi, and M. Yoshio, Determination of theoretical capacity of metal ion-doped LiMn2O4 as the positive electrode in Li-ion batteries. Journal of Power Sources, 1999. 77(2): p. 198-201.
29. D. Capsoni, M. Bini, G. Chiodelli, P. Mustarelli, V. Massarotti, C.B. Azzoni, M.C. Mozzati, and L. Linati, Inhibition of Jahn-Teller cooperative distortion in LiMn2O4 spinel by Ga3+ doping. Journal of Physical Chemistry B, 2002. 106(30): p. 7432-7438.
30. T. Zhang, D. Li, Z. Tao, and J. Chen, Understanding Electrode Materials of Rechargeable Lithium Batteries via DFT Calculations. Progress in Natural Science: Materials International, 2013. 23: p. 256Б─⌠272.
31. A.K. Padhi, K.S. Nanjundaswamy, and J.B. Goodenough, Phospho olivines as Positive Electrode Materials for Rechargeable Lithium Batteries. Journal of The Electrochemical Society, 1997. 144(4): p. 1188-1194.
32. G. Arnold, J. Garche, R. Hemmer, S. Strц╤bele, C. Vogler, and M. Wohlfahrt-Mehrens, Fine-particle lithium iron phosphate LiFePO4 synthesized by a new low-cost aqueous precipitation technique. Journal of Power Sources, 2003. 119-121: p. 247-251.
33. A.S. Andersson and J.O. Thomas, The source of first-cycle capacity loss in LiFePO4. Journal of Power Sources, 2001. 97: p. 498-502.
34. B. Ammundsen and J. Paulsen, Novel Lithium-Ion Cathode Materials Based on Layered Manganese Oxides. Advanced Materials - ADVAN MATER, 2001. 13: p. 943-956.
35. A. Chakraborty, S. Kunnikuruvan, S. Kumar, B. Markovsky, D. Aurbach, M. Dixit, and D.T. Major, Layered Cathode Materials for Lithium-Ion Batteries: Review of Computational Studies on LiNi1–x–yCoxMnyO2 and LiNi1–x–yCoxAlyO2. Chemistry of Materials, 2020. 32(3): p. 915-952.
36. H.D. Yoo, E. Markevich, G. Salitra, D. Sharon, and D. Aurbach, On the challenge of developing advanced technologies for electrochemical energy storage and conversion. Materials Today, 2014. 17(3): p. 110-121.
37. Q. Li, J. Chen, L. Fan, X. Kong, and Y. Lu, Progress in electrolytes for rechargeable Li-based batteries and beyond. Green Energy & Environment, 2016. 1(1): p. 18-42.
38. S.K. Heiskanen, J. Kim, and B.L. Lucht, Generation and Evolution of the Solid Electrolyte Interphase of Lithium-Ion Batteries. Joule, 2019. 3(10): p. 2322-2333.
39. B.T. Young, D.R. Heskett, C.C. Nguyen, M. Nie, J.C. Woicik, and B.L. Lucht, Hard X-ray Photoelectron Spectroscopy (HAXPES) Investigation of the Silicon Solid Electrolyte Interphase (SEI) in Lithium-Ion Batteries. ACS Applied Materials & Interfaces, 2015. 7(36): p. 20004-20011.
40. S. Lin and J. Zhao, Functional Electrolyte of Fluorinated Ether and Ester for Stabilizing Both 4.5 V LiCoO2 Cathode and Lithium Metal Anode. ACS Applied Materials & Interfaces, 2020. 12(7): p. 8316-8323.
41. T.M. Hagos, T.T. Hagos, H.K. Bezabh, G.B. Berhe, L.H. Abrha, S.-F. Chiu, C.-J. Huang, W.-N. Su, H. Dai, and B.J. Hwang, Resolving the Phase Instability of a Fluorinated Ether, Carbonate-Based Electrolyte for the Safe Operation of an Anode-Free Lithium Metal Battery. ACS Applied Energy Materials, 2020. 3(11): p. 10722-10733.
42. S. Dühnen, J. Betz, M. Kolek, R. Schmuch, M. Winter, and T. Placke, Toward Green Battery Cells: Perspective on Materials and Technologies. Small Methods, 2020. 4(7).
43. Z. Lu and J.R. Dahn, Understanding the Anomalous Capacity of Li/Li[Ni x]Li[(1/3−2x/3)]Mn[(2/3−x/3)]O2 Cells Using In Situ X-Ray Diffraction and Electrochemical Studies. Journal of The Electrochemical Society, 2002. 149(7).
44. Z. Lu, D.D. MacNeil, and J.R. Dahn, Layered Cathode Materials Li[NixLi[(1/3−2x/3)]Mn[(2/3−x/3)]O2 for Lithium-Ion Batteries. Electrochemical and Solid-State Letters, 2001. 4(11).
45. B.J. Hwang, C.J. Wang, C.H. Chen, Y.W. Tsai, and M. Venkateswarlu, Electrochemical properties of Li[NixLi(1-2x)/3Mn(2-x)/3]O2 (0<x<0.5) cathode materials prepared by a sol─gel process. Journal of Power Sources, 2005. 146(1): p. 658-663.
46. M.M. Thackeray, C.S. Johnson, J.T. Vaughey, N. Li, and S.A. Hackney, Advances in manganese-oxide composite electrodes for lithium-ion batteries. Journal of Materials Chemistry, 2005. 15(23): p. 2257-2267.
47. S.H. Lee, J.-S. Moon, M.-S. Lee, T.-H. Yu, H. Kim, and B.M. Park, Enhancing phase stability and kinetics of lithium-rich layered oxide for an ultra-high performing cathode in Li-ion batteries. Journal of Power Sources, 2015. 281: p. 77-84.
48. Z.Q. Deng and A. Manthiram, Influence of Cationic Substitutions on the Oxygen Loss and Reversible Capacity of Lithium-Rich Layered Oxide Cathodes. The Journal of Physical Chemistry C, 2011. 115(14): p. 7097-7103.
49. N. Guerrini, L. Jin, J.G. Lozano, K. Luo, A. Sobkowiak, K. Tsuruta, F. Massel, L.-C. Duda, M.R. Roberts, and P.G. Bruce, Charging Mechanism of Li2MnO3. Chemistry of Materials, 2020. 32(9): p. 3733-3740.
50. A.R. Armstrong, M. Holzapfel, P. Novц║k, C.S. Johnson, S.-H. Kang, M.M. Thackeray, and P.G. Bruce, Demonstrating Oxygen Loss and Associated Structural Reorganization in the Lithium Battery Cathode Li[Ni0.2Li0.2Mn0.6]O2. Journal of the American Chemical Society, 2006. 128(26): p. 8694-8698.
51. H. Koga, L. Croguennec, M. Mц╘nц╘trier, P. Mannessiez, F. Weill, C. Delmas, and S. Belin, Operando X-ray Absorption Study of the Redox Processes Involved upon Cycling of the Li-Rich Layered Oxide Li1.20Mn0.54Co0.13Ni0.13O2 in Li Ion Batteries. The Journal of Physical Chemistry C, 2014. 118(11): p. 5700-5709.
52. M. Sathiya, G. Rousse, K. Ramesha, C.P. Laisa, H. Vezin, M.T. Sougrati, M.L. Doublet, D. Foix, D. Gonbeau, W. Walker, A.S. Prakash, M. Ben Hassine, L. Dupont, and J.M. Tarascon, Reversible anionic redox chemistry in high-capacity layered-oxide electrodes. Nature Materials, 2013. 12(9): p. 827-835.
53. S. Hy, F. Felix, J. Rick, W.N. Su, and B.J. Hwang, Direct in situ observation of Li2O evolution on Li-rich high-capacity cathode material, Li[Ni(x)Li((1-2x)/3)Mn((2-x)/3)]O2 (0 </= x </= 0.5). J Am Chem Soc, 2014. 136(3): p. 999-1007.
54. R.A. House, G.J. Rees, M.A. Pérez-Osorio, J.-J. Marie, E. Boivin, A.W. Robertson, A. Nag, M. Garcia-Fernandez, K.-J. Zhou, and P.G. Bruce, First-cycle voltage hysteresis in Li-rich 3d cathodes associated with molecular O2 trapped in the bulk. Nature Energy, 2020. 5(10): p. 777-785.
55. M. Gu, I. Belharouak, J. Zheng, H. Wu, J. Xiao, A. Genc, K. Amine, S. Thevuthasan, D.R. Baer, J.-G. Zhang, N.D. Browning, J. Liu, and C. Wang, Formation of the Spinel Phase in the Layered Composite Cathode Used in Li-Ion Batteries. ACS Nano, 2013. 7(1): p. 760-767.
56. S.-L. Cui, Y.-Y. Wang, S. Liu, G.-R. Li, and X.-P. Gao, Evolution mechanism of phase transformation of Li-rich cathode materials in cycling. Electrochimica Acta, 2019. 328.
57. S. Hy, W.-N. Su, J.-M. Chen, and B.-J. Hwang, Soft X-ray Absorption Spectroscopic and Raman Studies on Li1.2Ni0.2Mn0.6O2 for Lithium-Ion Batteries. The Journal of Physical Chemistry C, 2012. 116(48): p. 25242-25247.
58. P. Oh, S. Myeong, W. Cho, M.-J. Lee, M. Ko, H.Y. Jeong, and J. Cho, Superior Long-Term Energy Retention and Volumetric Energy Density for Li-Rich Cathode Materials. Nano Letters, 2014. 14(10): p. 5965-5972.
59. P. Oh, J. Yun, S. Park, G. Nam, M. Liu, and J. Cho, Recent Advances and Prospects of Atomic Substitution on Layered Positive Materials for Lithium‐Ion Battery. Advanced Energy Materials, 2020. 11(15).
60. W. He, D. Yuan, J. Qian, X. Ai, H. Yang, and Y. Cao, Enhanced high-rate capability and cycling stability of Na-stabilized layered Li1.2[Co0.13Ni0.13Mn0.54]O2 cathode material. Journal of Materials Chemistry A, 2013. 1(37): p. 11397-11403.
61. M. Yang, B. Hu, F. Geng, C. Li, X. Lou, and B. Hu, Mitigating voltage decay in high-capacity Li1.2Ni0.2Mn0.6O2 cathode material by surface K+ doping. Electrochimica Acta, 2018. 291: p. 278-286.
62. J. Wang, M. Yang, C. Zhao, B. Hu, X. Lou, F. Geng, W. Tong, B. Hu, and C. Li, Unveiling the benefits of potassium doping on the structural integrity of Li-Mn-rich layered oxides during prolonged cycling by dual-mode EPR spectroscopy. Phys Chem Chem Phys, 2019. 21(43): p. 24017-24025.
63. H. Xu, S. Deng, and G. Chen, Improved electrochemical performance of Li1.2Mn0.54Ni0.13Co0.13O2 by Mg doping for lithium ion battery cathode material. J. Mater. Chem. A, 2014. 2(36): p. 15015-15021.
64. J. Chen, Y. Wang, N. Zhao, and Z.-Q. Liu, Hierarchical micro−nanostructured and Al3+−doped Li1.2Ni0.2Mn0.6O2 active materials with enhanced electrochemical properties as cathode materials for Li−ion batteries. Scripta Materialia, 2019. 171: p. 47-51.
65. G. Singh, R. Thomas, A. Kumar, and R.S. Katiyar, Electrochemical Behavior of Cr- Doped Composite Li2MnO3-LiMn0.5Ni0.5O2Cathode Materials. Journal of The Electrochemical Society, 2012. 159(4): p. A410-A420.
66. P.K. Nayak, J. Grinblat, M. Levi, O. Haik, E. Levi, and D. Aurbach, Effect of Fe in suppressing the discharge voltage decay of high capacity Li-rich cathodes for Li-ion batteries. Journal of Solid State Electrochemistry, 2015. 19(9): p. 2781-2792.
67. Y.-s. Jiang, G. Sun, F.-d. Yu, L.-f. Que, L. Deng, X.-h. Meng, and Z.-b. Wang, Surface modification by fluorine doping to increase discharge capacity of Li1.2Ni0.2Mn0.6O2 cathode materials. Ionics, 2019. 26(1): p. 151-161.
68. Y. Wang, H.-T. Gu, J.-H. Song, Z.-H. Feng, X.-B. Zhou, Y.-N. Zhou, K. Wang, and J.-Y. Xie, Suppressing Mn Reduction of Li-Rich Mn-Based Cathodes by F-Doping for Advanced Lithium-Ion Batteries. The Journal of Physical Chemistry C, 2018. 122(49): p. 27836-27842.
69. J. An, L. Shi, G. Chen, M. Li, H. Liu, S. Yuan, S. Chen, and D. Zhang, Insights into the stable layered structure of a Li-rich cathode material for lithium-ion batteries. Journal of Materials Chemistry A, 2017. 5(37): p. 19738-19744.
70. H.Z. Zhang, Q.Q. Qiao, G.R. Li, and X.P. Gao, PO43− polyanion-doping for stabilizing Li-rich layered oxides as cathode materials for advanced lithium-ion batteries. J. Mater. Chem. A, 2014. 2(20): p. 7454-7460.
71. Y. Zhao, J. Liu, S. Wang, R. Ji, Q. Xia, Z. Ding, W. Wei, Y. Liu, P. Wang, and D.G. Ivey, Surface Structural Transition Induced by Gradient Polyanion-Doping in Li-Rich Layered Oxides: Implications for Enhanced Electrochemical Performance. Advanced Functional Materials, 2016. 26(26): p. 4760-4767.
72. L. Ma, L. Mao, X. Zhao, J. Lu, F. Zhang, P. Ding, L. Chen, and F. Lian, Improving the Structural Stability of Li-Rich Layered Cathode Materials by Constructing an Antisite Defect Nanolayer through Polyanion Doping. ChemElectroChem, 2017. 4(12): p. 3068-3074.
73. H.-Z. Zhang, F. Li, G.-L. Pan, G.-R. Li, and X.-P. Gao, The Effect of Polyanion-Doping on the Structure and Electrochemical Performance of Li-Rich Layered Oxides as Cathode for Lithium-Ion Batteries. Journal of The Electrochemical Society, 2015. 162(9): p. A1899-A1904.
74. Y. Liu, D. Ning, L. Zheng, Q. Zhang, L. Gu, R. Gao, J. Zhang, A. Franz, G. Schumacher, and X. Liu, Improving the electrochemical performances of Li-rich Li1.20Ni0.13Co0.13Mn0.54O2 through a cooperative doping of Na+ and PO43− with Na3PO4. Journal of Power Sources, 2018. 375: p. 1-10.
75. Y. Wu and A. Manthiram, Effect of surface modifications on the layered solid solution cathodes (1−z) Li[Li1/3Mn2/3]O2−(z) Li[Mn0.5−yNi0.5−yCo2y]O2. Solid State Ionics, 2009. 180(1): p. 50-56.
76. F. Zheng, C. Yang, X. Xiong, J. Xiong, R. Hu, Y. Chen, and M. Liu, Nanoscale Surface Modification of Lithium-Rich Layered-Oxide Composite Cathodes for Suppressing Voltage Fade. Angew Chem Int Ed Engl, 2015. 54(44): p. 13058-62.
77. X. Zhang, R. Yu, Y. Huang, X. Wang, Y. Wang, B. Wu, Z. Liu, and J. Chen, The Influences of Surface Coating Layers on the Properties of Layered/Spinel Heterostructured Li-Rich Cathode Material. ACS Sustainable Chemistry & Engineering, 2018. 6(10): p. 12969-12979.
78. Z.H. Chen and J.R. Dahn, Methods to obtain excellent capacity retention in LiCoO2 cycled to 4.5 V. Electrochimica Acta, 2004. 49(7): p. 1079-1090.
79. B. Zhao, Y. Jiang, H. Zhang, H. Tao, M. Zhong, and Z. Jiao, Morphology and electrical properties of carbon coated LiFePO4 cathode materials. Journal of Power Sources, 2009. 189(1): p. 462-466.
80. W. Chang, J.-W. Choi, J.-C. Im, and J.K. Lee, Effects of ZnO coating on electrochemical performance and thermal stability of LiCoO2 as cathode material for lithium-ion batteries. Journal of Power Sources, 2010. 195(1): p. 320-326.
81. Y. Wang, B. Sun, J. Park, W.-S. Kim, H.-S. Kim, and G. Wang, Morphology control and electrochemical properties of nanosize LiFePO4 cathode material synthesized by co-precipitation combined with in situ polymerization. Journal of Alloys and Compounds, 2011. 509(3): p. 1040-1044.
82. V. Etacheri, Sol-Gel Processed Cathode Materials for Lithium-Ion Batteries, in Sol-Gel Materials for Energy, Environment and Electronic Applications. 2017. p. 155-195.
83. J. Cho, Y.J. Kim, and B. Park, Novel LiCoO2 cathode material with Al2O3 coating for a Li ion cell. Chemistry of Materials, 2000. 12(12): p. 3788-3791.
84. K. Gao, S.-X. Zhao, S.-T. Guo, and C.-W. Nan, Improving rate capacity and cycling performance of lithium-rich high-Mn Li1.8[Mn0.7Co0.15Ni0.15]O2.675 cathode materials by Li2SiO3 coating. Electrochimica Acta, 2016. 206: p. 1-9.
85. X. Xiong, D. Ding, Y. Bu, Z. Wang, B. Huang, H. Guo, and X. Li, Enhanced electrochemical properties of a LiNiO2-based cathode material by removing lithium residues with (NH4)2HPO4. J. Mater. Chem. A, 2014. 2(30): p. 11691-11696.
86. W. Zhang, L. Liang, F. Zhao, Y. Liu, L. Hou, and C. Yuan, Ni-rich LiNi0·8Co0·1Mn0·1O2 coated with Li-ion conductive Li3PO4 as competitive cathodes for high-energy-density lithium ion batteries. Electrochimica Acta, 2020. 340.
87. S. Li, J. Wu, J. Li, G. Liu, Y. Cui, and H. Liu, Facilitated Coating of Li3PO4 on the Rough Surface of LiNi0.85Co0.1Mn0.05O2 Cathodes by Synchronous Lithiation. ACS Applied Energy Materials, 2021. 4(3): p. 2257-2265.
88. Y. Lee, J. Lee, K.Y. Lee, J. Mun, J.K. Lee, and W. Choi, Facile formation of a Li3PO4 coating layer during the synthesis of a lithium-rich layered oxide for high-capacity lithium-ion batteries. Journal of Power Sources, 2016. 315: p. 284-293.
89. M.N. Ates, S. Mukerjee, and K.M. Abraham, A high rate Li-rich layered MNC cathode material for lithium-ion batteries. RSC Advances, 2015. 5(35): p. 27375-27386.
90. M.-H. Lin, J.-H. Cheng, H.-F. Huang, U.F. Chen, C.-M. Huang, H.-W. Hsieh, J.-M. Lee, J.-M. Chen, W.-N. Su, and B.-J. Hwang, Revealing the mitigation of intrinsic structure transformation and oxygen evolution in a layered Li 1.2 Ni 0.2 Mn 0.6 O 2 cathode using restricted charging protocols. Journal of Power Sources, 2017. 359: p. 539-548.
91. J. Meng, S. Zhang, X. Wei, P. Yang, S. Wang, J. Wang, H. Li, Y. Xing, and G. Liu, Synthesis, structure and electrochemical properties of lithium-rich cathode material Li1.2Mn0.6Ni0.2O2 microspheres. RSC Advances, 2015. 5(99): p. 81565-81572.
92. X-ray Photoelectron Spectroscopy (XPS) Reference Pages. Available from: https://www.xpsfitting.com/search?q=Li3PO4&max-results=20&by-date=true.
93. J.R. Croy, D. Kim, M. Balasubramanian, K. Gallagher, S.-H. Kang, and M.M. Thackeray, Countering the Voltage Decay in High Capacity xLi2MnO3•(1–x)LiMO2Electrodes (M=Mn, Ni, Co) for Li+-Ion Batteries. Journal of The Electrochemical Society, 2012. 159(6): p. A781-A790.
94. Q. Li, Y. Wang, X. Wang, X. Sun, J.N. Zhang, X. Yu, and H. Li, Investigations on the Fundamental Process of Cathode Electrolyte Interphase Formation and Evolution of High-Voltage Cathodes. ACS Appl Mater Interfaces, 2020. 12(2): p. 2319-2326.
95. R.A. Quinlan, Y.-C. Lu, Y. Shao-Horn, and A.N. Mansour, XPS Studies of Surface Chemistry Changes of LiNi0.5Mn0.5O2Electrodes during High-Voltage Cycling. Journal of The Electrochemical Society, 2013. 160(4): p. A669-A677.
96. R. Tatara, P. Karayaylali, Y. Yu, Y. Zhang, L. Giordano, F. Maglia, R. Jung, J.P. Schmidt, I. Lund, and Y. Shao-Horn, The Effect of Electrode-Electrolyte Interface on the Electrochemical Impedance Spectra for Positive Electrode in Li-Ion Battery. Journal of The Electrochemical Society, 2018. 166(3): p. A5090-A5098.