论文信息 - The first cycle characteristics of Li[Ni1/3Co1/3Mn1/3]O2 charged up to 4.7 V

The first cycle characteristics of Li[Ni1/3Co1/3Mn1/3]O2 charged up to 4.7 V

Abstract In this research, we studied the first cycle characteristics of Li[Ni1/3Co1/3Mn1/3]O2 charged up to 4.7 V. Properties, such as valence state of the transition metals and crystallographic features, were analyzed by X-ray absorption spectroscopy and X-ray and neutron diffractions. Especially, two plateaus observed around 3.75 and 4.54 V were investigated by ex situ X-ray absorption spectroscopy. XANES studies showed that the oxidation states of transition metals in Li[Ni1/3Co1/3Mn1/3]O2 are mostly Ni2+, Co3+ and Mn4+. Based on neutron diffraction Rietveld analysis, there is about 6% of all nickel divalent (Ni2+) ions mixed with lithium ions (cation mixing). Meanwhile, it was found that the oxidation reaction of Ni2+/Ni4+ is related to the lower plateau around 3.75 V, but that of Co3+/Co4+ seems to occur entire range of x in Li1−x[Ni1/3Co1/3Mn1/3]O2. Small volume change during cycling was attributed to the opposite variation of lattice parameter “c” and “a” with charging–discharging.

Jung-Min Kim | Hoon T. Chung | Jung-Min Kim | Hoon-Taek Chung | H. Chung

[1] I. Nakai,et al. Study of the Jahn–Teller Distortion in LiNiO2, a Cathode Material in a Rechargeable Lithium Battery, byin SituX-Ray Absorption Fine Structure Analysis☆ , 1998 .

[2] E. Zhecheva,et al. Changes in Structure and Cathode Performance with Composition and Preparation Temperature of Lithium Cobalt Nickel Oxide , 1998 .

[3] Zhonghua Lu,et al. Synthesis, Structure, and Electrochemical Behavior of Li [ Ni x Li1 / 3 − 2x / 3Mn2 / 3 − x / 3 ] O 2 , 2002 .

[4] R. D. Shannon. Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides , 1976 .

[5] T. Ohzuku,et al. Layered Lithium Insertion Material of LiCo1/3Ni1/3Mn1/3O2 for Lithium-Ion Batteries , 2001 .

[6] Tsutomu Ohzuku,et al. Crystal and electronic structures of superstructural Li1−x[Co1/3Ni1/3Mn1/3]O2 (0≤x≤1) , 2003 .

[7] Tsutomu Ohzuku,et al. Novel lithium insertion material of LiCo1/3Ni1/3Mn1/3O2 for advanced lithium-ion batteries , 2003 .

[8] G. Ceder,et al. Size and charge effects on the structural stability of LiMO2 (M = transition metal) compounds , 1998 .

[9] M. Yoshio,et al. In Situ XAFS Analysis of Li(Mn, M)2O4 (M=Cr, Co, Ni) 5V Cathode Materials for Lithium-Ion Secondary Batteries , 2001 .

[10] B. V. R. Chowdari,et al. Performance of layered Li(Ni1/3Co1/3Mn1/3)O2 as cathode for Li-ion batteries , 2002 .