Enhanced electrochemical performance of Lithium Metasilicate-coated LiNi0.6Co0.2Mn0.2O2 Ni-rich cathode for Li-ion batteries at high cutoff voltage. (20th December 2016)

• Record Type: Journal Article
• Authors: Wang, Lei; Mu, Daobin; Wu, Borong; Yang, Guchang; Gai, Liang; Liu, Qi; Fan, Yingjun; Peng, Yiyuan; Wu, Feng
• Is Part Of: Electrochimica acta. Volume 222(2016)
• Page Start: 806
• Page End: 813
• Publication Date: 2016-12-20
• Subjects: Lithium Metasilicate -- LiNi0.6Co0.2Mn0.2O2 -- Cathode material -- Cycle stability -- High voltage; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2016.11.041
• Languages: English
• ISSNs: 0013-4686

Abstract

Graphical abstract: Highlights: Li2 SiO3 -coated LiNi0.6 Co0.2 Mn0.2 O2 cathode is prepared by a direct and convenient method. The Li2 SiO3 -coated improves the cycle stability of the material. The 3.0 mol.% Li2 SiO3 -coated LiNi0.6 Co0.2 Mn0.2 O2 exhibits best electrochemistry properties. The Li2 SiO3 -coated LiNi0.6 Co0.2 Mn0.2 O2 presents excellent rate property. Abstract: Li2 SiO3 -coated LiNi0.6 Co0.2 Mn0.2 O2 cathode material has been synthesized and exhibit much better electrochemical performance than pristine LiNi0.6 Co0.2 Mn0.2 O2 at cut-off voltage 4.6 V. The as-prepared samples are characterized by X-ray diffraction, field emission scanning electron microscopy, field emission transmission electron microscope, and X-ray photoelectron spectroscopic. The results show that the coating-layer Li2 SiO3 is not incorporated into the LiNi0.6 Co0.2 Mn0.2 O2 host structure and coated well on the surface of the active material. The sample coated with 3 mol. % Li2 SiO3 delivers a capacity of 168 mAh g −1 at 0.2 C after 100 cycles, and remains 85.5% of the first discharge capacity. The capacity retention at 1C is 73.6% after 100 cycles and the first discharge capacity reaches 158 mAh g −1 at 10 C. This superior performance is attributed to the coating layer which restrains the side reactions at electrode/electrolyte interface and enhances structure stability, meanwhile, it can decrease the electrode polarization because it is an excellent Li + -ion conductor.