LiNi_(0.8-x)Zn_xCo_(0.2)O_2 的合成及电化学性能研究  

Synthesis and characterization of LiNi_(0.8-x)Zn_xCo_(0.2)O_2 as cathode materials for lithium-ion battery

作　　者：顾大明[1] 史鹏飞[1] 顾健[1] 谷芳[1] 高原[1] 

机构地区：[1]哈尔滨工业大学理学院,黑龙江哈尔滨150001

出　　处：《材料科学与工艺》2004年第6期586-589,共4页Materials Science and Technology

基　　金：黑龙江省自然科学基金资助项目(E2004-24);黑龙江省科技攻关资助项目(GZ04A307);哈尔滨市科技攻关资助项目(2004AA5CG077).

摘　　要：掺杂改性和表面修饰的LiNi0 8Co0 2O2是锂电池正极换代候选材料.采用共沉淀法制备了系列LiNi0 8-xZnxCo0 2O2材料,并对其进行X射线衍射(XRD)、扫描电镜(SEM)、循环伏安(CV)、电化学阻抗(EIS)和充放电循环性能(CP)测试分析.恒流循环(0 2C、3 0～4 2V)测试结果显示,Zn的掺入使材料的初始放电比容量有大幅增加,循环性能有所改善.其中LiNi0 78Zn0 02Co0 2O2的首次放电比容量达到206 37mAh·g-1.第30循环时,放电比容量仍为204 03mAh·g-1,不可逆容量损失仅为2 34mAh·g-1,显示了很好的初期循环性能.Doping-modified and surface-coating LiNi_(0.8)Co_(0.2)O_2 is a new promising candidate cathode matetials for lithium secondary batteries. A series of LiNi_(0.8-x)Zn_xCo_(0.2)O_2 cathode materials were synthesized by using a liquid phase coprecipitation method. The products were characterized by X-ray diffraction (XRD), scanning electronic microscopy (SEM), cycling voltammetry (CV),electrochemical impedance spectroscopy (EIS) and galvanostatic cycle(0.2C、3.0～4.2 V). As the results, the electrochemical properties of the materials were improved a lot by Zn-doped. The first discharge specific capacity of LiNi_(0.78)Zn_(0.02)Co_(0.2)O_2 was up to 206.37 mAh·g^(-1), The discharge specific capacity could still retain 204.03 mAh·g^(-1) after 30 cycles and the irreversible loss of the specific capacity only was 2.34 mAh·g^(-1), which revealed that the material had good initial stage cycling property.

关 键 词：比容量 循环性能 充放电 电化学性能 不可逆容量 正极 恒流 首次 初期 CP 

分 类 号：TB64[一般工业技术—制冷工程] TM912[电气工程—电力电子与电力传动]