Ternary cathode material was proved to have excellent electrochemical performance.However, this material had some de-fects such as cation mixing, low compaction density and charge-discharge efficiency, bad rate capability, poor high-temperature storage and cycle performance.LiNi0.8 Co0.15 Al0.05 O2/C cathode material was prepared by solid state reaction methods, which could improve the electrochemical performance of LiNi0.8 Co0.15 Al0.05 O2 .Effects of cladding contents including 1.02%, 2.01% and 2.97% ( mass fraction) on surface morphologies and electrochemical properties of materials were discussed respectively.Powder X-ray diffraction ( PXRD) and scanning electron microscope ( SEM) results confirmed that the sample microstructure wasα-NaFeO2 phase with spheri-cal morphology.The electrochemical? testing indicated that 2.01%C-coated sample showed the best electrochemical performance with the first discharge capacity of 175.5 mAh· g-1 at a charge-discharge rate of 0.1C, which was 10.5%higher than the pure phase mate-rial with 158.9 mAh· g-1 .And the capacity retention rates of 2.01% C-coated and uncoated material after 50 cycles at 3.0C were 88.2%and 75.6%, respectively.Lithium ion diffusion coefficient increased from 2.05 ×10 -13 to 3.76 ×10 -12 cm2· s-1 , and the cor-responding charge transfer impedance decreased from 79.4 to 53.6 Ω.
LiNi0.8 Co0.15 Al0.05 O2cathode materialsolid state reaction methodsC-coating
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