摘要

Spherical LiNi1/3Co1/3Mn1/3O2 particles were successfully synthesized using Na2CO3 as a precipitant. Electrochemical measurements indicate that the as-synthesized spherical particles deliver a high reversible capacity of above 180 mAh g(-1) at 0.1 C in the voltage range of 2.8-4.4 V and display an excellent cyclic performance at 0.5 C. However, unsatisfactory rate capability was detected for the as-prepared spherical particles. The reason for the unsatisfactory rate capability was investigated through a comparison of the properties of the as-synthesized spherical particles versus the ball-milled samples via a combination of specific surface areas test, electronic conductivity measurement, and electrochemical impedance spectroscopy. The results show that both the rate capabilities of cathode materials and the electronic conductivities of the mixtures of active material, conductive additive, and binder are highly improved when the secondary spherical particles were broken, indicating that the poor electronic conductivity of electrode caused by the large secondary spherical particles with a great amount of nano-pores is a significant factor for the unsatisfactory rate capability.

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