Nanophase LiCoO 2 was synthesized by solid state reaction with low heating temperature, i.e. the reactants Co(Ac) 2·4H 2O and LiOH·H 2O in the appropriate molar ratio(1∶1) were mixed and ground in agate mor...Nanophase LiCoO 2 was synthesized by solid state reaction with low heating temperature, i.e. the reactants Co(Ac) 2·4H 2O and LiOH·H 2O in the appropriate molar ratio(1∶1) were mixed and ground in agate mortar, then calcined. The samples obtained were characterized by XRD and IR methods. The phenomena during synthesizing are discussed by TG/TDA analysis, and the optimum temperature of heating was chosen. The BET and ICP results suggest that the sample has a large specific surface(54.29 m 2/g), a low quantity of impurity, thus it may be a good battery material. The nanophase LiCoO 2 samples produced have good cyclic performance and a higher working voltage plateau(3.9 V).展开更多
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 behavio...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 3.004.35 V((vs Li).) The results show that the prepared LiCoO2 powders calcinated at 900 ℃ 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.展开更多
LiCoO 2 powders were been synthesized by solid state coordination method and the process was discussed in detail by the thermal analysis.The structures were confirmed by XRD and SEM techniques.It proved that this meth...LiCoO 2 powders were been synthesized by solid state coordination method and the process was discussed in detail by the thermal analysis.The structures were confirmed by XRD and SEM techniques.It proved that this method had many advantages over the traditional high temperature solid state reaction.Electrochemical test proves the cathode material to have excellent electrochemical performance.展开更多
文摘Nanophase LiCoO 2 was synthesized by solid state reaction with low heating temperature, i.e. the reactants Co(Ac) 2·4H 2O and LiOH·H 2O in the appropriate molar ratio(1∶1) were mixed and ground in agate mortar, then calcined. The samples obtained were characterized by XRD and IR methods. The phenomena during synthesizing are discussed by TG/TDA analysis, and the optimum temperature of heating was chosen. The BET and ICP results suggest that the sample has a large specific surface(54.29 m 2/g), a low quantity of impurity, thus it may be a good battery material. The nanophase LiCoO 2 samples produced have good cyclic performance and a higher working voltage plateau(3.9 V).
文摘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 3.004.35 V((vs Li).) The results show that the prepared LiCoO2 powders calcinated at 900 ℃ 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.
文摘LiCoO 2 powders were been synthesized by solid state coordination method and the process was discussed in detail by the thermal analysis.The structures were confirmed by XRD and SEM techniques.It proved that this method had many advantages over the traditional high temperature solid state reaction.Electrochemical test proves the cathode material to have excellent electrochemical performance.