((中南大學(xué) 冶金科學(xué)與工程學(xué)院，長沙 410083))
摘 要: 采用溶膠−凝膠法合成摻雜F−的LiMn2O4。通過XRD、SEM對摻雜F−的LiMn2O4材料的組成、結(jié)構(gòu)、微觀形貌等進(jìn)行分析與表征，測試不同F-摻雜量的LiMn2O4在常溫(20 ℃)、高溫(55 ℃)下的電化學(xué)性能。結(jié)果表明：所合成的材料具有良好的尖晶石立方結(jié)構(gòu)，無雜相；F−的摻雜提高了材料的比容量，增強(qiáng)了材料的穩(wěn)定性，改善了其在高溫下的循環(huán)性能。當(dāng)F−的摻入量x由0增加到0.1時，材料的比容量由119.7 mA∙h/g增加到124.9 mA∙h/g，高溫下充放電30個循環(huán)后容量保持率由79.4%增加到84.4%。
關(guān)鍵字: 鋰離子電池；LiMn2O4；正極材料；離子摻雜
（(School of Metallurgical Science and Engineering, Central South University, Changsha 410083, China)）
Abstract:Spinel LiMn2O4 doped with F− was synthesized by sol-gel method. Its component, structure and morphology were studied by XRD and SEM. The electrochemical performance of the LiMn2O4 doped with F- was tested by constant current charge-discharge measurement at 20 ℃ and 55 ℃. The results show that the synthesized material is pure spinel phase. The electrochemical Li intercalation capacity of the synthesized cathode materials is improved, and the stability and cycle ability are enhanced at 55 ℃ due to the F-doping. As the amount of F− increases from 0 to 0.1, the capacity of the materials increases from 119.7 mA∙h/g to 124.9 mA∙h/g, and the rate of capacity retention after 30 cycles at 55 ℃ increases from 79.4% to 84.4%.
Key words: lithium ion batteries; LiMn2O4; cathode material; dope
