应用共沉淀结合固相烧结合成了富锂层状氧化物（Li-rich layered oxide，LLO）Li1.2Ni0.13Co0.13Mn0.54O2. 对制备的富锂材料用氧化石墨烯（Graphene Oxide，GO）包覆后，再经300 oC空气中煅烧，制备了石墨烯（Graphene，Gra）卷绕包覆的复合材料（LLO/Gra）. 使用扫描电镜（SEM）、透射电镜（TEM）、X射线衍射（XRD）和X射线光电子能谱（XPS）及电化学方法表征所得样品. 结果表明，富锂层状氧化物均匀地卷绕在石墨烯中. 与原始富锂材料相比，石墨烯包覆后的复合材料表现出更加优异的电化学性能. 尤其是石墨烯卷绕可以改善富锂材料的导电性，提高材料的放电倍率性能，在2.0至4.8 V电压范围内，0.1C（20 mA·g-1）电流充放电下，容量达270 mAh·g-1，1C倍率下复合物的放电容量接近200 mAh·g-1，比原始LLO材料170 mAh·g-1提高了15%.
In present work, lithium-rich layered transition metal oxide (LLO) was synthesized by a co-precipitation method in combination with a solid-state reaction. The graphene wrapped Li-rich layered oxide composite (LLO/Gra) was obtained by sintering the LLO/GO composite at 300 oC for 30 min in an air. The morphologies and the electrochemical performances were characterized by means of SEM, TEM, XRD, XPS, EIS and charge/discharge tests. The results indicated that the LLOe particles were uniformly wrapped with graphene. The resulting material exhibited better rate capability than that of pristine LLO since the wrapped graphene demonstrated the enhanced electronic conductivity. Accordingly, the capacity of 270 mAh·g-1 for the LLO/Gra composite could be obtained in a range of 2.0 to 4.8 V at 0.1C (20 mA·g-1), while approached to 200 mAh·g-1 at 1C, which is 15% higher than that of pristine LLO (170 mAh·g-1).
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