微波-固相复合加热技术合成LiNi_(0·5)Co_(0·5)O_2及其性能研究

Performances of Layered LiNi_(0.5)Co_(0.5)O_2 Prepared by Microwave-solid Phase Compound Heat Method

用高分子分散及微波-固相复合加热技术合成了层状锂离子电池正极材料L iN i0.5Co0.5O2.采用循环伏安、充放电循环、扫描电子显微镜(SEM)以及X射线粉末衍射(XRD)等测试技术,研究了煅烧条件对材料微观形貌、相结构以及电化学性能的影响规律.研究结果表明:在750℃煅烧4 h即可得到形状为类球形的纯相层状L iN i0.5Co0.5O2正极材料,该材料的最大放电容量达到154 mA.h/g,循环10周后放电容量仍保持在148 mA.h/g以上.

Layered cathode materials for lithium ion batteries, LiNi0.5Co0.5O2, was prepared by microwave- solid phase compound heat method using polyacrylamide （PAM） as template. The effects of calcination temperature and time on the electrochemical performance, crystal structure and morphology of the materials were studied by using cyclic voltammetry, XRD, SEM techniques and charge-discharge test. The results show that the discharge capacity reaches 154 mA · h/g for the material（with pure layer structure） calcined at 750 ℃ for 4 h. And it was still above 148 mA · h/g after ten cycles. At the same time, morphology of the material synthesized under the same conditions was sphere-like, which contributecl to increasing the density of electrode.