Structure and electrochemical properties of LiCoO₂ synthesized by microwave heating

Abstract

Microwave synthesis method was applied to the fast preparation of LiCoO₂. The structure of the synthesized oxides was analyzed by using X-ray diffraction. Only single-phase LiCoO₂ was obtained. Electrochemical behaviors of LiCoO₂ were investigated by charge-discharge cycling properties in the voltage range of 3.00 – 4.35 V (vs Li). The results show that the prepared LiCoO₂ powders calcinated at 900 °C for 120 min exhibit an initial charge and discharge capacity of 168 and 162 mA · h · g⁻¹ at 0.1C current rate, respectively, as compared to 159 and 154 mA · h · g⁻¹ of LiCoO₂ synthesized by conventional means. In addition, more than 95% of the capacity is retained even after 10 cycles. But with the increase of calcinating time, its electrochemical properties deteriorate. Compared with the conventional method, the microwave heating method is simple, fast, and with high energy efficiency.

Keywords

microwave synthesis method / Li-ion battery / cathode material / LiCoO₂

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