镍离子掺杂对LiFePO_4/C电化学性能的影响  

Effects on electrochemical performance of LiFePO_4/C via Ni doping

作　　者：章兴石[1,2] 肖方明[1] 王英[1] 肖志平[1] 唐仁衡[1] 

机构地区：[1]广东省工业技术研究院(广州有色金属研究院)稀有金属研究所,广东广州510650 [2]华南理工大学材料学院,广东广州510640

出　　处：《电源技术》2014年第12期2228-2230,共3页Chinese Journal of Power Sources

基　　金：珠海市战略性新兴产业重大项目;珠海市产学研合作专项资金(2011A05010003)

摘　　要：采用二步固相反应法合成了橄榄石型Li Fe0.98Ni0.02PO4/C复合正极材料。通过X射线衍射光谱法(XRD)、扫描电子显微镜法(SEM)、恒流充放电、循环伏安等手段表征了材料的物相结构及电化学性能。结果表明:Ni2+掺杂并未改变Li Fe PO4的晶体结构,但材料的颗粒尺寸减小(粒径约为200 nm),颗粒形貌近似球形;Li Fe0.98Ni0.02PO4/C材料具有良好的电化学性能,0.2 C下首次放电比容量可达143.7 m Ah/g,10 C下,放电比容量为106.9 m Ah/g。循环伏安测试表明Ni2+的掺杂提高了Li+在材料中脱嵌过程的可逆性。LiFe0.98Ni0.02PO4/C composite was synthesized by two-step solid state reaction. The experiment results show that the lattice structure of LiFePO4is not destroyed by Ni doping, but the particle morphology with a spherical particle size of 200 nm is improved; LiFe0.98Ni0.02PO4/C composite delivers 143.7 mAh/g, at the 0.2 C rate for the first cycles. At the high rates of 10 C, this material exhibits high capacities of 106.9 mAh/g. The CV results reveal that the reversibility of LiFePOJC composite could be improved by Ni doping.

关 键 词：磷酸铁锂 镍掺杂 锂离子电池 电化学性能 

分 类 号：TM912[电气工程—电力电子与电力传动]