Preparation of layered Li(Ni1/3Co1/3Mn1/3)O2 as positive material forlithium-ion secondary battery
(Department of Chemistry and Material Science, Hunan Institute of Humanities Science and Technology,
Loudi 417000, China)
Loudi 417000, China)
Abstract: The uniform layered Li(Ni1/3Co1/3Mn1/3)O2 cathode material for lithium-ion secondary batteries were synthesized by using (Ni1/3Co1/3Mn1/3)(OH)2 synthesized by a liquid phase co-precipitated method as precursors and with NiSO4, CoSO4, MnSO4 and NH3·H2O as raw materials. The influence of the preparation conditions such as precursors preparation, calcinations temperature and calcinations time on the structural and electrochemical properties of the Li(Ni1/3Co1/3Mn1/3)O2 were systematicelly studied. The result of XRD shows the I003/I104 value of the Li(Ni1/3Co1/3Mn1/3)O2 powder synthesized at 950 ℃ for 10 h is 1.26, which illustrates the well-ordered layer-structure. The average particle size of uniform Li(Ni1/3Co1/3Mn1/3)O2 powder is about 400 nm in diameter as observed by scanning electron microscopy. The first discharge capacity of Li(Ni1/3Co1/3Mn1/3)O2 electrode is 174.6 mA∙h/g at 16 mA/g between 2.8 V and 4.5 V versus Li at room temperature, and the capacity retention is 95.2% of the initial discharge capacity after 50 cycles at 32 mA/g.
Key words: Co-precipitation method; Li(Ni1/3Co1/3Mn1/3)O2; positive materials; lithium ion batteries