球形正极材料LiNi_(0.8-x)Co_(0.2)Al_xO_2的合成与表征  

Synthesis and Characterization of Spherical Cathode Materials LiNi_(0.8-x)Co_(0.2)Al_xO_2

作　　者：彭运吉[1] 叶乃清[1] 田华[1] 刘斌昌[1] 

机构地区：[1]桂林工学院有色金属及材料加工新技术教育部重点实验室材料与化学工程系,广西桂林541004

出　　处：《桂林工学院学报》2007年第4期557-561,共5页Journal of Guilin University of Technology

基　　金：广西自然科学基金资助项目(桂科自0575100);广西教育厅科研项目(0420022)

摘　　要：以LiNO3、Al(NO3)3.9H2O、Co(NO3)2.6H2O和球形Ni(OH)2为原料,采用熔盐包裹法在空气中合成了LiNi0.8-xCo0.2AlxO2.采用XRD、SEM和电池性能测试仪研究了合成产物的结构、形貌和电化学性能.考察了合成温度、合成时间、掺铝量和锂过量对合成产物结构的影响.实验表明,采用熔盐包裹法在空气中合成的LiNi0.8-xCo0.2AlxO2具有α-NaFeO2型层状有序结构和球状形貌,并具有良好的电化学性能,其中LiNi0.7Co0.2Al0.1O2的最大放电比容量达到157.7 mAh/g.在空气中合成LiNi0.8-xCo0.2AlxO2的最佳工艺条件为合成温度750℃,合成时间16 h,锂过量10%(摩尔分数).The single-phase solid solution of LiNi0. 8-x Co0. 2 AlxO2 is synthesized by molten salt coating method in air using LiNO3, Co（ NO3 ） · 6H2O2, Al（ NO3 ） 39H2O and spherical Ni（OH） 2 as starting materials. The crystal phases, structure and morphology of the final products are characterized by XRD and SEM. Their electrochemical performance is examined by charge-discharge test. The effects of the synthesited temperture, synthesized time, substituted amount of Al and excess Lithium on the structure of resulted products are tested. The experimental results show that the synthesized materials LiNi0. 8-x Co0. 2 AlxO2 present the α-NaFeO2 type, ordered and layered structure and spherical morphology with good electrochemical performace. The max discharging capacity of LiNi0. 7 Coo. 2 Alo. 102 is up to 157.7 mAh/g. The optimized conditions to synthesize LiNi0. 8-xCo0. 2 AlxO2 are 750 ℃ for 16 h, substituted about 10% aluminum for nickel and with 10% （ mole fraction） excess lithium in the starting materials.

关 键 词：锂离子电池 球形正极材料 LiNi0.8-xCo0.2AlxO2 熔盐包裹法 

分 类 号：TM912.9[电气工程—电力电子与电力传动]