摘要
通过静电纺丝法成功制备出尖晶石型LiMn_2O_4纳米纤维前驱丝,进一步在600~800℃之间对纳米纤维前驱丝进行煅烧,在700℃得到表面光滑且结晶度良好的LiMn_2O_4纳米纤维材料。通过X射线衍射可知LiMn_2O_4的结构为尖晶石型;通过扫描电镜发现LiMn_2O_4的直径约为350nm;再将LiMn_2O_4正极材料组装成扣式电池,通过测试其充放电性能,可知LiMn_2O_4正极材料在0.1C倍率下的首次充放电比容量分别为114.1和112mAh/g,在1C、2C、5C和10C倍率下的放电比容量分别为109.1、101.9、91.3和80.6mAh/g,而且在1C倍率下循环100次之后,容量保持率为92.7%;循环伏安曲线表明其两对氧化还原峰为3.92/4.10V和4.05/4.22V,是典型的尖晶石型LiMn_2O_4材料,且循环性能良好;由交流阻抗图谱可知LiMn_2O_4样品的电荷转移阻抗约为622.21Ω。
LiMn_2O_4 nanofibres were prepared by electrospinning technique combined with annealing.LiMn_2O_4 nanofibres had a smooth morphology and the single phase with high crystallinity after being annealing at 700℃.XRD revealed that LiMn_2O_4 nanofibres possessed the spinel structure.SEM images showed that the diameter of LiMn_2O_4 nanofibres was 350 nm.Then accessory materials were performed into coin-type Li battery in the glove box and sequentially assembled.The initial charge capacity and discharge capacity were 114.1 mAh/g and 112 mAh/g at 0.1 C,respectively.And the discharge capacity was 109.1 mAh/g,101.9 mAh/g,91.3 mAh/g and 80.6 mAh/g at 1 C,2 C,5 C,and 10 C,respectively.The capacity retention of 92.7% after 100 cycles under 1 C.CV showed that the characteristic two-step redox peaks were at 3.92/4.10 Vand 4.05/4.22 V,which were characteristic peaks of LiMn_2O_4.The EIS spectrum showed that the charge-transfer resistance Rctof LiMn_2O_4 was 622.21Ω.
作者
戴剑锋
闫兴山
田西光
李维学
王青
Dai Jianfeng;Yan Xingshan;Tian Xiguang;Li Weixue;Wang Qing(State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals, Lanzhou 730050;School of Science, Lanzhou University of Technology, Lanzhou 730050)
出处
《化工新型材料》
CAS
CSCD
北大核心
2018年第5期204-207,共4页
New Chemical Materials
关键词
锂离子电池
正极材料
静电纺丝
纳米纤维
lithium-ion battery
anode material
electrospinning
nanofibres
