钴镍掺杂锰酸锂的电化学性能研究

采用固相烧结法分别制备了钴掺杂和镍掺杂锰酸锂锂离子电池正极材料,同时制备了纯相锰酸锂进行比较.用电感耦合等离子发射光谱仪、X射线衍射仪、电子扫描电镜和电池性能测试系统对产物的组成、结构特征、微观表面形貌和恒流充放电性能进行了表征.结果表明:所制备的掺杂锰酸锂LiMn0.9 Ni0.1O2、LiMn0.9 Co0.1O2的结晶度高,无杂质相,材料颗粒的粒径均匀、表面光滑;首次放电比容量分别为114.7mAh/g和110.8mAh/g(0.5mA/cm,2.8~4.4V,vs.Li+/Li);50次循环后,放电比容量为107.2mAh/g和103.3mAh/g,50次循环比容量保持率分别达到94.1%和95.4%.

Electrochemical characterization of LiMn2O4

Solid state sinter method was used to synthesize the Co-doped and Ni-doped LiMn2O4cathode materials of Li-ion batteries respectively, and the pure LiMn2O4was prepared to compare with them. The composition, microstructure, morphology and cycle properties of the products were characterized by inductive coupled plasma atomic emission spectrometry (ICP-AES), X-ray diffraction (XRD), scanning electronic microscopy (SEM) and galvanostatic cycle respectively. The results showed that the prepared material was the structure of spinel phase lithium manganate with high crystallinity and without impurity phase; the size of the particles was well distributed;the first discharge specific capacities of the LiMn1.9Ni0.1O4 and LiMn1.9Co0.1O4 were 114.7 mAh/g and 110.8 mAh/g(0.5 mA/cm,2.8 ～ 4.4 V,vs. Li+/Li);the discharge specific capacities could still retain 107.2 mAh/g and 103.3 mAh/g after 50 cycles, the specific capacity retention were 94.1% and 95.4% respectively.