摘要
用TG、DSC实验结果讨论了以Li2 CO3和电解MnO2 为原料合成尖晶石型LiMn2 O4 的温度选择。用X—射线衍射、循环伏安、恒电流充放电等手段研究了合成样品的性能。TG、DSC实验结果表明 ,电解MnO2 在 5 42℃开始分解成Mn2 O3;Li2 CO3在 6 18℃开始熔融 ,718℃分解 ;Li2 CO3和电解MnO2 的混合物在 70 1℃时形成尖晶石型LiMn2 O4 。据此提出在 2 0 0 ,6 0 0 ,70 1,80 0℃分段保温一定时间的加热程序 ,可以得到纯尖晶石的锂锰氧化物。循环伏安和恒电流充放电结果表明 。
In this paper, the option for synthetic temperature of spinel lithium manganese oxide from electrolytic MnO 2 and Li 2CO 3 was discussed with the results of TG and DSC, and some properties of a synthesized sample were studied with XRD? cyclic voltammetry? constant current charge and discharge. It was shown by TG and DSC that electrolytic MnO 2 decomposed at 542℃ to Mn 2O 3, Li 2CO 3 was melt at 618℃ and decomposed at 718℃, and spinel LiMn 2O 4 formed at 701℃ when the mixture of electrolytic MnO 2 and Li 2CO 3 was heated. Based on these results, a temperature program was proposed for the synthesis of spinel LiMn 2O 4 from electrolytic MnO 2 and Li 2CO 3: 200, 600, 701℃ and 800℃ for a certain time, respectively. It was shown by cyclic voltammetry? constant current charge and discharge that mechanism of the synthesized product was two steps of Li ion insertion and extraction.
出处
《中国锰业》
2002年第1期15-19,共5页
China Manganese Industry
基金
广州科委资助课题 (98-Z - 0 77- 0 1)
关键词
尖晶石锂锰氧化物
合成温度
循环伏安
恒电流放电
锂离子电池
正极材料
spinel lithium manganese oxide
synthetic temperature
crystal structure
cyclic voltammetry
constant current discharge
